Epoch of reionization 21 cm forecasting from MCMC-constrained semi-numerical models
NASA Astrophysics Data System (ADS)
Hassan, Sultan; Davé, Romeel; Finlator, Kristian; Santos, Mario G.
2017-06-01
The recent low value of Planck Collaboration XLVII integrated optical depth to Thomson scattering suggests that the reionization occurred fairly suddenly, disfavouring extended reionization scenarios. This will have a significant impact on the 21 cm power spectrum. Using a semi-numerical framework, we improve our model from instantaneous to include time-integrated ionization and recombination effects, and find that this leads to more sudden reionization. It also yields larger H II bubbles that lead to an order of magnitude more 21 cm power on large scales, while suppressing the small-scale ionization power. Local fluctuations in the neutral hydrogen density play the dominant role in boosting the 21 cm power spectrum on large scales, while recombinations are subdominant. We use a Monte Carlo Markov chain approach to constrain our model to observations of the star formation rate functions at z = 6, 7, 8 from Bouwens et al., the Planck Collaboration XLVII optical depth measurements and the Becker & Bolton ionizing emissivity data at z ˜ 5. We then use this constrained model to perform 21 cm forecasting for Low Frequency Array, Hydrogen Epoch of Reionization Array and Square Kilometre Array in order to determine how well such data can characterize the sources driving reionization. We find that the Mock 21 cm power spectrum alone can somewhat constrain the halo mass dependence of ionizing sources, the photon escape fraction and ionizing amplitude, but combining the Mock 21 cm data with other current observations enables us to separately constrain all these parameters. Our framework illustrates how the future 21 cm data can play a key role in understanding the sources and topology of reionization as observations improve.
Focusing Events and Constrains on Policy Addressing Long-Term Climate Change Risks
NASA Astrophysics Data System (ADS)
O'Donovan, K.
2014-12-01
When policy makers are aware of immediate and long-term risks to communities, what do they do to plan for and mitigate the effects of climate change? This paper addresses that question in two ways. First, as an organizing framework it presents an overview of the empirical evidence on focusing events. Focusing events are defined as sudden, rare events that reveal harm or the potential for future harm that the general public and policy makers become aware of simultaneously. These large-scale events are typically natural and disasters, crisis, or technological accidents. This paper considers the empirical evidence of the relationship between focusing events, the harm revealed by the event and policy change aimed at reducing future risk of harm. Second, this paper reviews the case of flood mitigation policy in the United States from 1968 to 2008. It considers the ways in which policy makers have and have not integrated future flood risks into mitigation policy and planning, particularly after large-scale floods. It analyzes the political, intergovernmental, demographic and geographic factors that have promoted and constrained long-term flood mitigation policy. This paper concludes with a discussion of the meaning and implications of potential focusing events and constrains on policy for long-term climate change concerns.
Constraints on pulsar masses from the maximum observed glitch
NASA Astrophysics Data System (ADS)
Pizzochero, P. M.; Antonelli, M.; Haskell, B.; Seveso, S.
2017-07-01
Neutron stars are unique cosmic laboratories in which fundamental physics can be probed in extreme conditions not accessible to terrestrial experiments. In particular, the precise timing of rotating magnetized neutron stars (pulsars) reveals sudden jumps in rotational frequency in these otherwise steadily spinning-down objects. These 'glitches' are thought to be due to the presence of a superfluid component in the star, and offer a unique glimpse into the interior physics of neutron stars. In this paper we propose an innovative method to constrain the mass of glitching pulsars, using observations of the maximum glitch observed in a star, together with state-of-the-art microphysical models of the pinning interaction between superfluid vortices and ions in the crust. We study the properties of a physically consistent angular momentum reservoir of pinned vorticity, and we find a general inverse relation between the size of the maximum glitch and the pulsar mass. We are then able to estimate the mass of all the observed glitchers that have displayed at least two large events. Our procedure will allow current and future observations of glitching pulsars to constrain not only the physics of glitch models but also the superfluid properties of dense hadronic matter in neutron star interiors.
Sudden unexpected death in epilepsy genetics: Molecular diagnostics and prevention.
Goldman, Alica M; Behr, Elijah R; Semsarian, Christopher; Bagnall, Richard D; Sisodiya, Sanjay; Cooper, Paul N
2016-01-01
Epidemiologic studies clearly document the public health burden of sudden unexpected death in epilepsy (SUDEP). Clinical and experimental studies have uncovered dynamic cardiorespiratory dysfunction, both interictally and at the time of sudden death due to epilepsy. Genetic analyses in humans and in model systems have facilitated our current molecular understanding of SUDEP. Many discoveries have been informed by progress in the field of sudden cardiac death and sudden infant death syndrome. It is becoming apparent that SUDEP genomic complexity parallels that of sudden cardiac death, and that there is a pauci1ty of analytically useful postmortem material. Because many challenges remain, future progress in SUDEP research, molecular diagnostics, and prevention rests in international, collaborative, and transdisciplinary dialogue in human and experimental translational research of sudden death. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.
Sudden Event Recognition: A Survey
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
Forecasting the future of coast live oak forests in the face of sudden oak death
Letty B. Brown; Barbara Allen-Diaz
2006-01-01
Little is known about the potential short- and long-term impacts of sudden oak death (SOD) on forest structure and composition. This study began in 2002 to evaluate the effects of SOD on coast live oak (Quercus agrifolia) - California bay laurel (Umbellularia californica) forests over a gradient of Phytophthora ramorum...
Y.S. Valachovic; C.A. Lee; H. Scanlon; J.M. Varner; R. Glebocki; B.D. Graham; D.M. Rizzo
2011-01-01
We compared stand structure and fuel loading in northwestern California forests invaded by Phytophthora ramorum, the cause of sudden oak death, to assess whether the continued presence of this pathogen alters surface fuel loading and potential fire behavior in ways that may encumber future firefighting response. To attempt to account for these...
Krous, Henry F; Haas, Elisabeth A; Manning, Julie M; Deeds, Anita; Silva, Patricia D; Chadwick, Amy E; Stanley, Christina
2006-08-01
The potential diagnostic significance of prior family referral to Child Protective Services (CPS) in cases of sudden infant death is unknown. Therefore, the authors retrospectively searched for CPS data for the 5-year referral history on all 533 families whose infants died suddenly from Sudden Infant Death Syndrome (SIDS), other natural diseases, accidents, or inflicted injuries and underwent postmortem examination by the medical examiner during a 10-year period. No family had more than one infant death. At least 27% of the families in each group had at least one CPS referral. The data suggest that a family's referral to CPS prior to their sudden death of their infant does not increase the likelihood that it was caused by inflicted injuries, and prior referral should not preclude a diagnosis of SIDS. The authors recommend future prospective studies that include refined exposure histories and that are large enough to have sufficient statistical power to compare family CPS referrals and outcomes in groups of infants who died suddenly with a matched group of living infants.
Structural imaging biomarkers of sudden unexpected death in epilepsy
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
2015-01-01
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. PMID:26264515
NASA Astrophysics Data System (ADS)
da Costa, F. Rubio
2017-10-01
While progress has been made on understanding how energy is released and deposited along the solar atmosphere during explosive events such as solar flares, the chromospheric and coronal heating through the sudden release of magnetic energy remain an open problem in solar physics. Recent hydrodynamic models allow to investigate the energy deposition along a flare loop and to study the response of the chromosphere. These results have been improved with the consideration of transport and acceleration of particles along the loop. RHESSI and Fermi/GBM X-ray and gamma-ray observations help to constrain the spectral properties of the injected electrons. The excellent spatial, spectral and temporal resolution of IRIS will also help us to constrain properties of explosive events, such as the continuum emission during flares or their emission in the chromosphere.
Long-term monitoring of sudden oak death in Marin County and the East Bay Hills
Brice A. McPherson; Greg Biging; Maggi Kelly; David L. Wood
2017-01-01
Prior to 2000 the etiology, effects on host trees, and possible consequences for northern Californiaâs forests of the syndrome known as sudden oak death were unknown. We designed a plot-based study to address these issues and to set a baseline for future evaluations.In March-April 2000 we established a total of 20 plots in two forested...
Inheritance of Febrile Seizures in Sudden Unexplained Death in Toddlers
Holm, Ingrid A.; Poduri, Annapurna; Crandall, Laura; Haas, Elisabeth; Grafe, Marjorie R.; Kinney, Hannah C.; Krous, Henry F.
2014-01-01
Sudden unexplained death in toddlers has been associated with febrile seizures, family history of febrile seizures, and hippocampal anomalies. We investigated the mode of inheritance for febrile seizures in these families. A three-generation pedigree was obtained from families enrolled in the San Diego Sudden Unexplained Death in Childhood Research Project, involving toddlers with sudden unexplained death, febrile seizures, and family history of febrile seizures. In our six cases, death was unwitnessed and related to sleep. The interval from last witnessed febrile seizure to death ranged from 3 weeks to 6 months. Hippocampal abnormalities were identified in one of three cases with available autopsy sections. Autosomal dominant inheritance of febrile seizures was observed in three families. A fourth demonstrated autosomal dominant inheritance with incomplete penetrance or variable expressivity. In two families, the maternal and paternal sides manifested febrile seizures. In this series, the major pattern of inheritance in toddlers with sudden unexplained death and febrile seizures was autosomal dominant. Future studies should develop markers (including genetic) to identify which patients with febrile seizures are at risk for sudden unexplained death in childhood, and to provide guidance for families and physicians. PMID:22490769
Sudden Unexpected Death in Fetal Life Through Early Childhood
Kinney, Hannah C.; Willinger, Marian
2016-01-01
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. PMID:27230764
NASA Astrophysics Data System (ADS)
Laing, Kevin J. C.; Russamono, Thais
2013-02-01
The likelihood of trained astronauts developing a life threatening cardiac event during spaceflight is relatively rare, whilst the incidence in untrained individuals is unknown. Space tourists who live a sedentary lifestyle have reduced cardiovascular function, but the associated danger of sudden cardiac arrest (SCA) during a suborbital spaceflight (SOSF) is unclear. Risk during SOSF was examined by reviewing several microgravity studies and methods of determining poor cardiovascular condition. Accurately assessing cardiovascular function and improving baroreceptor sensitivity through exercise is suggested to reduce the incidence of SCA during future SOSFs. Future studies will benefit from past participants sharing medical history; allowing creation of risk profiles and suitable guidelines.
Tapered whiskers are required for active tactile sensation.
Hires, Samuel Andrew; Pammer, Lorenz; Svoboda, Karel; Golomb, David
2013-11-19
Many mammals forage and burrow in dark constrained spaces. Touch through facial whiskers is important during these activities, but the close quarters makes whisker deployment challenging. The diverse shapes of facial whiskers reflect distinct ecological niches. Rodent whiskers are conical, often with a remarkably linear taper. Here we use theoretical and experimental methods to analyze interactions of mouse whiskers with objects. When pushed into objects, conical whiskers suddenly slip at a critical angle. In contrast, cylindrical whiskers do not slip for biologically plausible movements. Conical whiskers sweep across objects and textures in characteristic sequences of brief sticks and slips, which provide information about the tactile world. In contrast, cylindrical whiskers stick and remain stuck, even when sweeping across fine textures. Thus the conical whisker structure is adaptive for sensor mobility in constrained environments and in feature extraction during active haptic exploration of objects and surfaces. DOI: http://dx.doi.org/10.7554/eLife.01350.001.
Sudden cardiac death in adults with congenital heart disease.
Yap, Sing-Chien; Harris, Louise
2009-12-01
Sudden cardiac death is one of the leading causes of death in patients with congenital heart disease, especially in patients with repaired cyanotic and left heart obstructive lesions. While the overall annual incidence of sudden cardiac death is relatively low, estimated at 0.09% per year, this nonetheless represents a many-fold increase over that of comparable age-matched control populations. The most frequent cause of sudden cardiac death is believed to be arrhythmic, usually ventricular arrhythmia. Most studies investigating risk factors for ventricular arrhythmia and/or sudden cardiac death have focused on patients with repaired tetralogy of Fallot and patients with Mustard/Senning repair for complete transposition of the great arteries. Despite a multitude of risk factors, their predictive value for the occurrence of sudden cardiac death is relatively low. Current experience with implantable cardioverter defibrillators in this patient population is limited to observational studies and the selection of patients for prophylactic implantable cardioverter defibrillator implantation is impeded both by the absence of randomized trials and weak predictors. Catheter ablation of ventricular tachycardia has emerged as a promising therapy for abolishing or reducing the burden of arrhythmia but experience is still limited and the impact on long-term outcome uncertain. Future studies will have to focus on improving risk stratification of patients with congenital heart disease.
Laukkanen, Jari A.; Mäkikallio, Timo H.; Rauramaa, Rainer; Kurl, Sudhir
2009-01-01
Aims Silent electrocardiographic ST change predicts future coronary events in patients with coronary heart disease (CHD), but the prognostic significance of asymptomatic ST-segment depression with respect to sudden cardiac death in subjects without apparent CHD is not well known. Methods and results We investigated the association between silent ST-segment depression during and after maximal symptom-limited exercise test and the risk of sudden cardiac death in a population-based sample of 1769 men without evident CHD. A total of 72 sudden cardiac death occurred during the median follow-up of 18 years. The risk of sudden cardiac death was increased among men with asymptomatic ST-segment depression during exercise [hazard ratio (HR) 2.1, 95% confidence interval (CI) 1.2–3.9] as well as among those with asymptomatic ST-segment depression during recovery period (HR 3.2, 95% CI 1.7–6.0). Asymptomatic ST-depression during exercise testing was a stronger predictor for the risk of sudden cardiac death especially among smokers as well as in hypercholesterolaemic and hypertensive men than in men without these risk factors. Conclusion Asymptomatic ST-segment depression was a very strong predictor of sudden cardiac death in men with any conventional risk factor but no previously diagnosed CHD, emphasizing the value of exercise testing to identify asymptomatic high-risk men who could benefit from preventive measures. PMID:19168533
The Year 2000: Teacher Education.
ERIC Educational Resources Information Center
Van Til, William
In speculating about the future, scholar-prophets can account for future social changes (such as those induced by computer technology) by extrapolating current trends, but "systems breaks," or sudden changes in the characteristics of a system (caused by biological transformations for instance) may invalidate their predictions. With that in mind,…
Risk factors and causes of sudden noncardiac death: A nationwide cohort study in Denmark.
Risgaard, Bjarke; Lynge, Thomas Hadberg; Wissenberg, Mads; Jabbari, Reza; Glinge, Charlotte; Gislason, Gunnar Hilmar; Haunsø, Stig; Winkel, Bo Gregers; Tfelt-Hansen, Jacob
2015-05-01
On the performance of an autopsy, sudden deaths may be divided into 2 classifications: (1) sudden cardiac deaths and (2) sudden noncardiac deaths (SNCDs). Families of SNCD victims should not be followed up as a means of searching for cardiac disease. The purpose of this study was to report the risk factors and causes of SNCD. 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 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. We identified 1039 autopsied cases of sudden death, of which 286 (28%) were classified as SNCD. The median age in the SNCD death population was 32 years. Increasing age was inversely associated with SNCD (odds ratio [OR] 0.93, 95% confidence interval [CI] 0.87-0.98). Female sex, in-hospital location, and the absence of cardiac comorbidities were positively associated with SNCD (OR 1.7, 95% CI 1.3-2.3; 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%]). Sudden death among individuals aged <50 years was caused by noncardiac diseases in 28% of cases. Risk factors were female sex, age, and the absence of cardiac comorbidities. These data may guide future strategies for the follow-up of family members of nonautopsied sudden death victims, improve risk stratification, and influence public health strategies. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
Why the Future Doesn't Come from Machines: Unfounded Prophecies and the Design of Naturoids
ERIC Educational Resources Information Center
Negrotti, Massimo
2008-01-01
Technological imagination and actual technological achievements have always been two very different things. Sudden and unpredictable events always seem to intervene between our visions regarding possible futures and the subsequent concrete realizations. Thus, our ideas and projects are continually being redirected. In the field of…
Intracardiac electrophysiology study (EPS)
... rhythm Determine whether you are at risk for future heart events, especially sudden cardiac death See if ... patient with suspected arrhythmia. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: ...
Reproductive Decision Making and Genetic Predisposition to Sudden Cardiac Death
Barlevy, Dorit; Wasserman, David; Stolerman, Marina; Erskine, Kathleen E.; Dolan, Siobhan M.
2012-01-01
Background With current genetic technology, it is possible to detect mutations associated with long QT syndrome (LQTS), a hereditary cardiac arrhythmia syndrome. As a result, prospective parents diagnosed with LQTS will have to decide whether or not to prevent its transmission to future generations, either by not procreating or through the use of assisted reproductive technologies or prenatal testing. This paper explores how a hereditary predisposition to sudden cardiac death can influence reproductive decision making. Methods This study draws from interviews and focus groups with individuals who have personal or family histories of cardiac arrhythmia or sudden death. A keyword search was conducted on interview transcripts to identify quotes for analysis. Results Participants expressed complex, often ambivalent attitudes about the prospect of having a child with a predisposition to sudden cardiac death. Their comments reveal conflicting understandings of genetic responsibility and reflect the variable effects of personal experience on reproductive decision making. This paper compares attitudes towards LQTS and other genetic conditions in analyzing the themes that emerged in interviews and focus groups. Conclusions The “disability critique” of prenatal testing should be applied carefully to a context of genetic predisposition to sudden cardiac death in order to understand reproductive decision making. Firsthand experience with the condition, among other factors, can weigh heavily in those decisions. PMID:22822470
Systematic review of the incidence of sudden cardiac death in the United States.
Kong, Melissa H; Fonarow, Gregg C; Peterson, Eric D; Curtis, Anne B; Hernandez, Adrian F; Sanders, Gillian D; Thomas, Kevin L; Hayes, David L; Al-Khatib, Sana M
2011-02-15
The need for consistent and current data describing the true incidence of sudden cardiac arrest (SCA) and/or sudden cardiac death (SCD) was highlighted during the most recent Sudden Cardiac Arrest Thought Leadership Alliance's (SCATLA) Think Tank meeting of national experts with broad representation of key stakeholders, including thought leaders and representatives from the American College of Cardiology, American Heart Association, and the Heart Rhythm Society. As such, to evaluate the true magnitude of this public health problem, we performed a systematic literature search in MEDLINE using the MeSH headings, "death, sudden" OR the terms "sudden cardiac death" OR "sudden cardiac arrest" OR "cardiac arrest" OR "cardiac death" OR "sudden death" OR "arrhythmic death." Study selection criteria included peer-reviewed publications of primary data used to estimate SCD incidence in the U.S. We used Web of Science's Cited Reference Search to evaluate the impact of each primary estimate on the medical literature by determining the number of times each "primary source" has been cited. The estimated U.S. annual incidence of SCD varied widely from 180,000 to >450,000 among 6 included studies. These different estimates were in part due to different data sources (with data age ranging from 1980 to 2007), definitions of SCD, case ascertainment criteria, methods of estimation/extrapolation, and sources of case ascertainment. The true incidence of SCA and/or SCD in the U.S. remains unclear, with a wide range in the available estimates that are badly dated. As reliable estimates of SCD incidence are important for improving risk stratification and prevention, future efforts are clearly needed to establish uniform definitions of SCA and SCD and then to prospectively and precisely capture cases of SCA and SCD in the overall U.S. population. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Research Priorities in Sudden Unexpected Infant Death: An International Consensus.
Hauck, Fern R; McEntire, Betty L; Raven, Leanne K; Bates, Francine L; Lyus, Lucy A; Willett, Alexis M; Blair, Peter S
2017-07-27
Despite the success of safe sleep campaigns and the progress in understanding risk factors, the rate of reduction in the cases of sudden infant death syndrome has now slowed and it remains a leading cause of postneonatal mortality in many developed countries. Strategic action is needed to tackle this problem and it is now vital to identify how the sudden infant death research community may best target its efforts. The Global Action and Prioritization of Sudden Infant Death Project was an international consensus process that aimed to define and direct future research by investigating the priorities of expert and lay members of the sudden unexpected infant death (SUID) community across countries. The aim was to identify which areas of research should be prioritized to reduce the number of SUID deaths globally. Scientific researchers, clinicians, counselors, educators, and SUID parents from 25 countries took part across 2 online surveys to identify potential research priorities. Workshops subsequently took place in the United Kingdom, United States, and Australia to reach consensus and 10 priority areas for research were established. Three main themes among the priorities emerged: (1) a better understanding of mechanisms underlying SUID, (2) ensuring best practice in data collection, management and sharing, and (3) a better understanding of target populations and more effective communication of risk. SUID is a global problem and this project provides the international SUID community with a list of shared research priorities to more effectively work toward explaining and reducing the number of sudden infant deaths. Copyright © 2017 by the American Academy of Pediatrics.
NASA Astrophysics Data System (ADS)
Limpasuvan, Varavut; Orsolini, Yvan J.; Chandran, Amal; Garcia, Rolando R.; Smith, Anne K.
2016-05-01
Based on a climate-chemistry model (constrained by reanalyses below ~50 km), the zonal-mean composite response of the mesosphere and lower thermosphere (MLT) to major sudden stratospheric warming events with elevated stratopauses demonstrates the role of planetary waves (PWs) in driving the mean circulation in the presence of gravity waves (GWs), helping the polar vortex recover and communicating the sudden stratospheric warming (SSW) impact across the equator. With the SSW onset, strong westward PW drag appears above 80 km primarily from the dissipation of wave number 1 perturbations with westward period of 5-12 days, generated from below by the unstable westward polar stratospheric jet that develops as a result of the SSW. The filtering effect of this jet also allows eastward propagating GWs to saturate in the winter MLT, providing eastward drag that promotes winter polar mesospheric cooling. The dominant PW forcing translates to a net westward drag above the eastward mesospheric jet, which initiates downwelling over the winter pole. As the eastward polar stratospheric jet returns, this westward PW drag persists above 80 km and acts synergistically with the return of westward GW drag to drive a stronger polar downwelling that warms the pole adiabatically and helps reform the stratopause at an elevated altitude. With the polar wind reversal during the SSW onset, the westward drag by the quasi-stationary PW in the winter stratosphere drives an anomalous equatorial upwelling and cooling that enhance tropical stratospheric ozone. Along with equatorial wind anomalies, this ozone enhancement subsequently amplifies the migrating semidiurnal tide amplitude in the winter midlatitudes.
Cosmic shear as a probe of galaxy formation physics
Foreman, Simon; Becker, Matthew R.; Wechsler, Risa H.
2016-09-01
Here, we evaluate the potential for current and future cosmic shear measurements from large galaxy surveys to constrain the impact of baryonic physics on the matter power spectrum. We do so using a model-independent parametrization that describes deviations of the matter power spectrum from the dark-matter-only case as a set of principal components that are localized in wavenumber and redshift. We perform forecasts for a variety of current and future data sets, and find that at least ~90 per cent of the constraining power of these data sets is contained in no more than nine principal components. The constraining powermore » of different surveys can be quantified using a figure of merit defined relative to currently available surveys. With this metric, we find that the final Dark Energy Survey data set (DES Y5) and the Hyper Suprime-Cam Survey will be roughly an order of magnitude more powerful than existing data in constraining baryonic effects. Upcoming Stage IV surveys (Large Synoptic Survey Telescope, Euclid, and Wide Field Infrared Survey Telescope) will improve upon this by a further factor of a few. We show that this conclusion is robust to marginalization over several key systematics. The ultimate power of cosmic shear to constrain galaxy formation is dependent on understanding systematics in the shear measurements at small (sub-arcminute) scales. Lastly, if these systematics can be sufficiently controlled, cosmic shear measurements from DES Y5 and other future surveys have the potential to provide a very clean probe of galaxy formation and to strongly constrain a wide range of predictions from modern hydrodynamical simulations.« less
Lessons Learned from a Decade of Sudden Oak Death in California: Evaluating Local Management
NASA Astrophysics Data System (ADS)
Alexander, Janice; Lee, Christopher A.
2010-09-01
Sudden Oak Death has been impacting California’s coastal forests for more than a decade. In that time, and in the absence of a centrally organized and coordinated set of mandatory management actions for this disease in California’s wildlands and open spaces, many local communities have initiated their own management programs. We present five case studies to explore how local-level management has attempted to control this disease. From these case studies, we glean three lessons: connections count, scale matters, and building capacity is crucial. These lessons may help management, research, and education planning for future pest and disease outbreaks.
Lessons Learned from a Decade of Sudden Oak Death in California: Evaluating Local Management
Alexander, Janice
2010-01-01
Sudden Oak Death has been impacting California’s coastal forests for more than a decade. In that time, and in the absence of a centrally organized and coordinated set of mandatory management actions for this disease in California’s wildlands and open spaces, many local communities have initiated their own management programs. We present five case studies to explore how local-level management has attempted to control this disease. From these case studies, we glean three lessons: connections count, scale matters, and building capacity is crucial. These lessons may help management, research, and education planning for future pest and disease outbreaks. PMID:20559634
Modeling Volcanic Eruption Parameters by Near-Source Internal Gravity Waves.
Ripepe, M; Barfucci, G; De Angelis, S; Delle Donne, D; Lacanna, G; Marchetti, E
2016-11-10
Volcanic explosions release large amounts of hot gas and ash into the atmosphere to form plumes rising several kilometers above eruptive vents, which can pose serious risk on human health and aviation also at several thousands of kilometers from the volcanic source. However the most sophisticate atmospheric models and eruptive plume dynamics require input parameters such as duration of the ejection phase and total mass erupted to constrain the quantity of ash dispersed in the atmosphere and to efficiently evaluate the related hazard. The sudden ejection of this large quantity of ash can perturb the equilibrium of the whole atmosphere triggering oscillations well below the frequencies of acoustic waves, down to much longer periods typical of gravity waves. We show that atmospheric gravity oscillations induced by volcanic eruptions and recorded by pressure sensors can be modeled as a compact source representing the rate of erupted volcanic mass. We demonstrate the feasibility of using gravity waves to derive eruption source parameters such as duration of the injection and total erupted mass with direct application in constraining plume and ash dispersal models.
Modeling Volcanic Eruption Parameters by Near-Source Internal Gravity Waves
Ripepe, M.; Barfucci, G.; De Angelis, S.; Delle Donne, D.; Lacanna, G.; Marchetti, E.
2016-01-01
Volcanic explosions release large amounts of hot gas and ash into the atmosphere to form plumes rising several kilometers above eruptive vents, which can pose serious risk on human health and aviation also at several thousands of kilometers from the volcanic source. However the most sophisticate atmospheric models and eruptive plume dynamics require input parameters such as duration of the ejection phase and total mass erupted to constrain the quantity of ash dispersed in the atmosphere and to efficiently evaluate the related hazard. The sudden ejection of this large quantity of ash can perturb the equilibrium of the whole atmosphere triggering oscillations well below the frequencies of acoustic waves, down to much longer periods typical of gravity waves. We show that atmospheric gravity oscillations induced by volcanic eruptions and recorded by pressure sensors can be modeled as a compact source representing the rate of erupted volcanic mass. We demonstrate the feasibility of using gravity waves to derive eruption source parameters such as duration of the injection and total erupted mass with direct application in constraining plume and ash dispersal models. PMID:27830768
2014-01-01
Background There are many potential causes of sudden and severe headache (thunderclap headache), the most important of which is aneurysmal subarachnoid haemorrhage. Published academic reviews report a wide range of causes. We sought to create a definitive list of causes, other than aneurysmal subarachnoid haemorrhage, using a systematic review. Methods Systematic Review of EMBASE and MEDLINE databases using pre-defined search criteria up to September 2009. We extracted data from any original research paper or case report describing a case of someone presenting with a sudden and severe headache, and summarized the published causes. Results Our search identified over 21,000 titles, of which 1224 articles were scrutinized in full. 213 articles described 2345 people with sudden and severe headache, and we identified 6 English language academic review articles. A total of 119 causes were identified, of which 46 (38%) were not mentioned in published academic review articles. Using capture-recapture analysis, we estimate that our search was 98% complete. There is only one population-based estimate of the incidence of sudden and severe headache at 43 cases per 100,000. In cohort studies, the most common causes identified were primary headaches or headaches of uncertain cause. Vasoconstriction syndromes are commonly mentioned in case reports or case series. The most common cause not mentioned in academic reviews was pneumocephalus. 70 non-English language articles were identified but these did not contain additional causes. Conclusions There are over 100 different published causes of sudden and severe headache, other than aneurysmal subarachnoid haemorrhage. We have now made a definitive list of causes for future reference which we intend to maintain. There is a need for an up to date population based description of cause of sudden and severe headache as the modern epidemiology of thunderclap headache may require updating in the light of research on cerebral vasoconstriction syndromes. PMID:25123846
Gimeno-Blanes, Francisco J.; Blanco-Velasco, Manuel; Barquero-Pérez, Óscar; García-Alberola, Arcadi; Rojo-Álvarez, José L.
2016-01-01
Great effort has been devoted in recent years to the development of sudden cardiac risk predictors as a function of electric cardiac signals, mainly obtained from the electrocardiogram (ECG) analysis. But these prediction techniques are still seldom used in clinical practice, partly due to its limited diagnostic accuracy and to the lack of consensus about the appropriate computational signal processing implementation. This paper addresses a three-fold approach, based on ECG indices, to structure this review on sudden cardiac risk stratification. First, throughout the computational techniques that had been widely proposed for obtaining these indices in technical literature. Second, over the scientific evidence, that although is supported by observational clinical studies, they are not always representative enough. And third, via the limited technology transfer of academy-accepted algorithms, requiring further meditation for future systems. We focus on three families of ECG derived indices which are tackled from the aforementioned viewpoints, namely, heart rate turbulence (HRT), heart rate variability (HRV), and T-wave alternans. In terms of computational algorithms, we still need clearer scientific evidence, standardizing, and benchmarking, siting on advanced algorithms applied over large and representative datasets. New scenarios like electronic health recordings, big data, long-term monitoring, and cloud databases, will eventually open new frameworks to foresee suitable new paradigms in the near future. PMID:27014083
Considering Future Potential Regarding Structural Diversity in Selection of Forest Reserves.
Lundström, Johanna; Öhman, Karin; Rönnqvist, Mikael; Gustafsson, Lena
2016-01-01
A rich structural diversity in forests promotes biodiversity. Forests are dynamic and therefore it is crucial to consider future structural potential when selecting reserves, to make robust conservation decisions. We analyzed forests in boreal Sweden based on 17,599 National Forest Inventory (NFI) plots with the main aim to understand how effectiveness of reserves depends on the time dimension in the selection process, specifically by considering future structural diversity. In the study both the economic value and future values of 15 structural variables were simulated during a 100 year period. To get a net present structural value (NPSV), a single value covering both current and future values, we used four discounting alternatives: (1) only considering present values, (2) giving equal importance to values in each of the 100 years within the planning horizon, (3) applying an annual discount rate considering the risk that values could be lost, and (4) only considering the values in year 100. The four alternatives were evaluated in a reserve selection model under budget-constrained and area-constrained selections. When selecting young forests higher structural richness could be reached at a quarter of the cost over almost twice the area in a budget-constrained selection compared to an area-constrained selection. Our results point to the importance of considering future structural diversity in the selection of forest reserves and not as is done currently to base the selection on existing values. Targeting future values increases structural diversity and implies a relatively lower cost. Further, our results show that a re-orientation from old to young forests would imply savings while offering a more extensive reserve network with high structural qualities in the future. However, caution must be raised against a drastic reorientation of the current old-forest strategy since remnants of ancient forests will need to be prioritized due to their role for disturbance-sensitive species.
NASA Astrophysics Data System (ADS)
Vacchi, Matteo; Rovere, Alessio; Marriner, Nick; Morhange, Christophe; Spada, Giorgio; Fontana, Alessandro
2016-04-01
After the review of 918 radiocarbon dated Relative Sea-Level (RSL) data-points we present here the first quality-controlled database constraining the Holocene sea-level histories of the western Mediterranean Sea (Spain, France, Italy, Slovenia, Croatia, Malta and Tunisia). We reviewed and standardized the geological RSL data-points using a new multi-proxy methodology based on: (1) modern taxa assemblages in Mediterranean lagoons and marshes; (2) beachrock characteristics (cement fabric and chemistry, sedimentary structures); and (3) the modern distribution of Mediterranean fixed biological indicators. These RSL data-points were coupled with the large number of archaeological RSL indicators available for the western Mediterranean. We assessed the spatial variability of RSL histories for 22 regions and compared these with the ICE-5G VM2 GIA model. In the western Mediterranean, RSL rose continuously for the whole Holocene with a sudden slowdown at ~7.5 ka BP and a further deceleration during the last ~4.0 ka BP, after which time observed RSL changes are mainly related to variability in isostatic adjustment. The sole exception is southern Tunisia, where data show evidence of a mid-Holocene high-stand compatible with the isostatic impacts of the melting history of the remote Antarctic ice sheet. Our results indicate that late-Holocene sea-level rise was significantly slower than the current one. First estimates of GIA contribution indicate that, at least in the northwestern sector, it accounts at least for the 25-30% of the ongoing sea-level rise recorded by Mediterranean tidal gauges. Such contribution is less constrained at lower latitudes due to the lower quality of the late Holocene index points. Future applications of spatio-temporal statistical techniques are required to better quantify the gradient of the isostatic contribution and to provide improved context for the assessment of 20th century acceleration of Mediterranean sea-level rise.
A precise measurement of the magnetic field in the corona of the black hole binary V404 Cygni
NASA Astrophysics Data System (ADS)
Dallilar, Yigit; Eikenberry, Stephen S.; Garner, Alan; Stelter, Richard D.; Gottlieb, Amy; Gandhi, Poshak; Casella, Piergiorgio; Dhillon, Vik S.; Marsh, Tom R.; Littlefair, Stuart P.; Hardy, Liam; Fender, Rob; Mooley, Kunal; Walton, Dominic J.; Fuerst, Felix; Bachetti, Matteo; Castro-Tirado, A. J.; Charcos, Miguel; Edwards, Michelle L.; Lasso-Cabrera, Nestor M.; Marin-Franch, Antonio; Raines, S. Nicholas; Ackley, Kendall; Bennett, John G.; Cenarro, A. Javier; Chinn, Brian; Donoso, H. Veronica; Frommeyer, Raymond; Hanna, Kevin; Herlevich, Michael D.; Julian, Jeff; Miller, Paola; Mullin, Scott; Murphey, Charles H.; Packham, Chris; Varosi, Frank; Vega, Claudia; Warner, Craig; Ramaprakash, A. N.; Burse, Mahesh; Punnadi, Sujit; Chordia, Pravin; Gerarts, Andreas; de Paz Martín, Héctor; Calero, María Martín; Scarpa, Riccardo; Acosta, Sergio Fernandez; Hernández Sánchez, William Miguel; Siegel, Benjamin; Pérez, Francisco Francisco; Viera Martín, Himar D.; Rodríguez Losada, José A.; Nuñez, Agustín; Tejero, Álvaro; Martín González, Carlos E.; Rodríguez, César Cabrera; Molgó, Jordi; Rodriguez, J. Esteban; Cáceres, J. Israel Fernández; Rodríguez García, Luis A.; Lopez, Manuel Huertas; Dominguez, Raul; Gaggstatter, Tim; Lavers, Antonio Cabrera; Geier, Stefan; Pessev, Peter; Sarajedini, Ata
2017-12-01
The binary system V404 Cygni consists of a red giant star orbiting a black hole. In 2015, a surge of accretion by the black hole caused the surrounding plasma to brighten suddenly for the first time since 1989, briefly becoming the brightest x-ray source in the sky. Dallilar et al. combined observations from radio, infrared, optical, and x-ray telescopes taken during the outburst. They compared how fast the flux decayed at each wavelength, which allowed them to constrain the size of the emitting region, determine that the plasma within it cooled through synchrotron radiation, and measure the magnetic field around the black hole.
Constraining the interaction between dark sectors with future HI intensity mapping observations
NASA Astrophysics Data System (ADS)
Xu, Xiaodong; Ma, Yin-Zhe; Weltman, Amanda
2018-04-01
We study a model of interacting dark matter and dark energy, in which the two components are coupled. We calculate the predictions for the 21-cm intensity mapping power spectra, and forecast the detectability with future single-dish intensity mapping surveys (BINGO, FAST and SKA-I). Since dark energy is turned on at z ˜1 , which falls into the sensitivity range of these radio surveys, the HI intensity mapping technique is an efficient tool to constrain the interaction. By comparing with current constraints on dark sector interactions, we find that future radio surveys will produce tight and reliable constraints on the coupling parameters.
Ecological Interactions Affecting the Efficacy of Aphidius colemani in Greenhouse Crops
Prado, Sara G.; Jandricic, Sarah E.; Frank, Steven D.
2015-01-01
Aphidius colemani Viereck (Hymenoptera: Braconidae) is a solitary endoparasitoid used for biological control of many economically important pest aphids. Given its widespread use, a vast array of literature on this natural enemy exists. Though often highly effective for aphid suppression, the literature reveals that A. colemani efficacy within greenhouse production systems can be reduced by many stressors, both biotic (plants, aphid hosts, other natural enemies) and abiotic (climate and lighting). For example, effects from 3rd and 4th trophic levels (fungal-based control products, hyperparasitoids) can suddenly decimate A. colemani populations. But, the most chronic negative effects (reduced parasitoid foraging efficiency, fitness) seem to be from stressors at the first trophic level. Negative effects from the 1st trophic level are difficult to mediate since growers are usually constrained to particular plant varieties due to market demands. Major research gaps identified by our review include determining how plants, aphid hosts, and A. colemani interact to affect the net aphid population, and how production conditions such as temperature, humidity and lighting affect both the population growth rate of A. colemani and its target pest. Decades of research have made A. colemani an essential part of biological control programs in greenhouse crops. Future gains in A. colemani efficacy and aphid biological control will require an interdisciplinary, systems approach that considers plant production and climate effects at all trophic levels. PMID:26463203
Erskine, Kathleen E.; Hidayatallah, Nadia Z.; Walsh, Christine A.; McDonald, Thomas V.; Cohen, Lilian; Marion, Robert W.; Dolan, Siobhan M.
2014-01-01
Genetic testing is becoming increasingly available for cardiac channelopathies, such as long QT syndrome and Brugada syndrome, which can lead to sudden cardiac death. Test results can be used to shape an individual’s medical management and to identify at-risk family members. In our qualitative study, all participants had a personal or family history of a diagnosed cardiac arrhythmia syndrome or sudden cardiac death. Open-ended interviews were conducted individually and in focus groups. Interviews were audio recorded, transcribed verbatim, and analyzed using a qualitative grounded-theory approach. Of 50 participants, 37 described their motivations for pursuing genetic testing for long QT syndrome or another cardiac channelopathy. Participants’ motivations included: to find an explanation for a family member’s sudden death, to relieve uncertainty regarding a diagnosis, to guide future medical management, to allay concern about children or other family members, and to comply with recommendations of physicians or family members. Perceived reasons not to pursue genetic testing included denial, fear, and lack of information. The genetic counseling and informed consent process can be enhanced by understanding and addressing an individual’s internal and external motivations either for or against pursuing genetic testing. PMID:24664857
Tharakaraman, Kannan; Watanabe, Satoru; Chan, Kuan Rong; Huan, Jia; Subramanian, Vidya; Chionh, Yok Hian; Raguram, Aditya; Quinlan, Devin; McBee, Megan; Ong, Eugenia Z; Gan, Esther S; Tan, Hwee Cheng; Tyagi, Anu; Bhushan, Shashi; Lescar, Julien; Vasudevan, Subhash G; Ooi, Eng Eong; Sasisekharan, Ram
2018-05-09
Following the recent emergence of Zika virus (ZIKV), many murine and human neutralizing anti-ZIKV antibodies have been reported. Given the risk of virus escape mutants, engineering antibodies that target mutationally constrained epitopes with therapeutically relevant potencies can be valuable for combating future outbreaks. Here, we applied computational methods to engineer an antibody, ZAb_FLEP, that targets a highly networked and therefore mutationally constrained surface formed by the envelope protein dimer. ZAb_FLEP neutralized a breadth of ZIKV strains and protected mice in distinct in vivo models, including resolving vertical transmission and fetal mortality in infected pregnant mice. Serial passaging of ZIKV in the presence of ZAb_FLEP failed to generate viral escape mutants, suggesting that its epitope is indeed mutationally constrained. A single-particle cryo-EM reconstruction of the Fab-ZIKV complex validated the structural model and revealed insights into ZAb_FLEP's neutralization mechanism. ZAb_FLEP has potential as a therapeutic in future outbreaks. Copyright © 2018. Published by Elsevier Inc.
[Primary prevention of sudden cardiac death through a wearable cardioverter-defibrillator].
Gabrielli, Domenico; Benvenuto, Manuela; Baroni, Matteo; Oliva, Fabrizio; Capucci, Alessandro
2015-01-01
Nowadays, the implantable cardioverter-defibrillator is the gold standard for the prevention of sudden cardiac death due to tachyarrhythmias. However, its use is not free from short and long-term risks. In the last years, the wearable cardioverter-defibrillator (WCD) has become a widespread option for patients who need a safe and reversible protection against ventricular tachyarrhythmias. Notwithstanding this, its everyday application is restricted by several limitations, including the risk of inappropriate shocks, the device size and the need for strict compliance of both patients and caregivers. In this review, we report the most relevant literature data on WCD usage along with the main fields of applications and future perspectives.
Phytophthora ramorum regulatory program: present, past, and future direction
Prakash Hebbar; Scott Pfister; Stacy Scott; Anthony Man-Son-Hing; Russ Bulluck
2013-01-01
Sudden oak death (SOD), caused by Phytophthora ramorum, is lethal to tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh), and threatens this species throughout its range in Oregon. The disease was first discovered in coastal southwest Oregon forests in July 2001. Since then an interagency team...
The Evolution from Generation to Post-XX
ERIC Educational Resources Information Center
Feng, Zhao
2011-01-01
Young people represent the future, and youth is an eternal topic. In the 1970s when the American anthropologist Margaret Mead published her famous work "Generation Gap," research on generations gained sudden popularity worldwide, and ever since the 1980s when "Generation Gap" was brought to China, research by scholars in this…
Leaving a Community College Presidency: The Inevitable Career Transition
ERIC Educational Resources Information Center
Floyd, Deborah L.; Maslin-Ostrowski, Patricia
2013-01-01
This article provides a succinct synthesis of research about community college presidents who have experienced a crisis or dilemma as leaders and focuses on issues surrounding a sudden and unplanned departure. In addition to describing themes, the authors present implications for leaders and potential areas for future research.
Mikami, Yoko; Jolly, Umjeet; Heydari, Bobak; Peng, Mingkai; Almehmadi, Fahad; Zahrani, Mohammed; Bokhari, Mahmoud; Stirrat, John; Lydell, Carmen P; Howarth, Andrew G; Yee, Raymond; White, James A
2017-01-01
Left ventricular ejection fraction remains the primary risk stratification tool used in the selection of patients for implantable cardioverter defibrillator therapy. However, this solitary marker fails to identify a substantial portion of patients experiencing sudden cardiac arrest. In this study, we examined the incremental value of considering right ventricular ejection fraction for the prediction of future arrhythmic events in patients with systolic dysfunction using the gold standard of cardiovascular magnetic resonance. Three hundred fourteen consecutive patients with ischemic cardiomyopathy or nonischemic dilated cardiomyopathy undergoing cardiovascular magnetic resonance were followed for the primary outcome of sudden cardiac arrest or appropriate implantable cardioverter defibrillator therapy. Blinded quantification of left ventricular and right ventricular (RV) volumes was performed from standard cine imaging. Quantification of fibrosis from late gadolinium enhancement imaging was incrementally performed. RV dysfunction was defined as right ventricular ejection fraction ≤45%. Among all patients (164 ischemic cardiomyopathy, 150 nonischemic dilated cardiomyopathy), the mean left ventricular ejection fraction was 32±12% (range, 6-54%) with mean right ventricular ejection fraction of 48±15% (range, 7-78%). At a median of 773 days, 49 patients (15.6%) experienced the primary outcome (9 sudden cardiac arrest, 40 appropriate implantable cardioverter defibrillator therapies). RV dysfunction was independently predictive of the primary outcome (hazard ratio=2.98; P=0.002). Among those with a left ventricular ejection fraction >35% (N=121; mean left ventricular ejection fraction, 45±6%), RV dysfunction provided an adjusted hazard ratio of 4.2 (P=0.02). RV dysfunction is a strong, independent predictor of arrhythmic events. Among patients with mild to moderate LV dysfunction, a cohort greatly contributing to global sudden cardiac arrest burden, this marker provides robust discrimination of high- versus low-risk subjects. © 2017 American Heart Association, Inc.
NASA Astrophysics Data System (ADS)
Kim, Hyomin; Clauer, C. Robert; Gerrard, Andrew J.; Engebretson, Mark J.; Hartinger, Michael D.; Lessard, Marc R.; Matzka, Jürgen; Sibeck, David G.; Singer, Howard J.; Stolle, Claudia; Weimer, Daniel R.; Xu, Zhonghua
2017-07-01
We report on simultaneous observations of electromagnetic ion cyclotron (EMIC) waves associated with traveling convection vortex (TCV) events caused by transient solar wind dynamic pressure (Pd) impulse events. The Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft located near the magnetopause observed radial fluctuations of the magnetopause, and the GOES spacecraft measured sudden compressions of the magnetosphere in response to sudden increases in Pd. During the transient events, EMIC waves were observed by interhemispheric conjugate ground-based magnetometer arrays as well as the GOES spacecraft. The spectral structures of the waves appear to be well correlated with the fluctuating motion of the magnetopause, showing compression-associated wave generation. In addition, the wave features are remarkably similar in conjugate hemispheres in terms of bandwidth, quasiperiodic wave power modulation, and polarization. Proton precipitation was also observed by the DMSP spacecraft during the wave events, from which the wave source region is estimated to be 72°-74° in magnetic latitude, consistent with the TCV center. The confluence of space-borne and ground instruments including the interhemispheric, high-latitude, fluxgate/induction coil magnetometer array allows us to constrain the EMIC source region while also confirming the relationship between EMIC waves and the TCV current system.
NASA Astrophysics Data System (ADS)
McCormack, J. P.; Sassi, F.; Hoppel, K.; Ma, J.; Eckermann, S. D.
2015-12-01
We investigate the evolution of neutral atmospheric dynamics in the 10-100 km altitude range before, during, and after recent stratospheric sudden warmings (SSWs) using a prototype high-altitude version of the Navy Global Environmental Model (NAVGEM), which combines a 4-dimensional variational (4DVAR) data assimilation system with a 3-time-level semi-Lagrangian semi-implicit global forecast model. In addition to assimilating conventional meteorological observations, NAVGEM also assimilates middle atmospheric temperature and constituent observations from both operational and research satellite platforms to provide global synoptic meteorological analyses of winds, temperatures, ozone, and water vapor from the surface to ~90 km. In this study, NAVGEM analyses are used to diagnose the spatial and temporal evolution of the main dynamical drivers in the mesosphere and lower thermosphere (MLT) before, during, and after specific SSW events during the 2009-2013 period when large disturbances were observed in the thermosphere/ionosphere (TI) region. Preliminary findings show strong modulation of the semidiurnal tide in the MLT during the onset of an SSW. To assess the impact of the neutral atmosphere dynamical variability on the TI system, NAVGEM analyses are used to constrain simulations of select SSW events using the specified dynamics (SD) configuration of the extended Whole Atmosphere Community Climate Model (WACCM-X).
NASA Astrophysics Data System (ADS)
Polcari, Marco; Fernández, José; Albano, Matteo; Bignami, Christian; Palano, Mimmo; Stramondo, Salvatore
2017-12-01
In this work, we propose an improved algorithm to constrain the 3D ground displacement field induced by fast surface deformations due to earthquakes or landslides. Based on the integration of different data, we estimate the three displacement components by solving a function minimization problem from the Bayes theory. We exploit the outcomes from SAR Interferometry (InSAR), Global Positioning System (GNSS) and Multiple Aperture Interferometry (MAI) to retrieve the 3D surface displacement field. Any other source of information can be added to the processing chain in a simple way, being the algorithm computationally efficient. Furthermore, we use the intensity Pixel Offset Tracking (POT) to locate the discontinuity produced on the surface by a sudden deformation phenomenon and then improve the GNSS data interpolation. This approach allows to be independent from other information such as in-situ investigations, tectonic studies or knowledge of the data covariance matrix. We applied such a method to investigate the ground deformation field related to the 2014 Mw 6.0 Napa Valley earthquake, occurred few kilometers from the San Andreas fault system.
NASA Astrophysics Data System (ADS)
iMOST Team; Harrington, A. D.; Carrier, B. L.; Fernandez-Remolar, D. C.; Fogarty, J.; McCoy, J. T.; Rucker, M. A.; Spry, J. A.; Altieri, F.; Amelin, Y.; Ammannito, E.; Anand, M.; Beaty, D. W.; Benning, L. G.; Bishop, J. L.; Borg, L. E.; Boucher, D.; Brucato, J. R.; Busemann, H.; Campbell, K. A.; Czaja, A. D.; Debaille, V.; Des Marais, D. J.; Dixon, M.; Ehlmann, B. L.; Farmer, J. D.; Glavin, D. P.; Goreva, Y. S.; Grady, M. M.; Hallis, L. J.; Hausrath, E. M.; Herd, C. D. K.; Horgan, B.; Humayun, M.; Kleine, T.; Kleinhenz, J.; Mangold, N.; Mackelprang, R.; Mayhew, L. E.; McCubbin, F. M.; McLennan, S. M.; McSween, H. Y.; Moser, D. E.; Moynier, F.; Mustard, J. F.; Niles, P. B.; Ori, G. G.; Raulin, F.; Rettberg, P.; Schmitz, N.; Sefton-Nash, E.; Sephton, M. A.; Shaheen, R.; Shuster, D. L.; Siljestrom, S.; Smith, C. L.; Steele, A.; Swindle, T. D.; ten Kate, I. L.; Tosca, N. J.; Usui, T.; Van Kranendonk, M. J.; Wadhwa, M.; Weiss, B. P.; Werner, S. C.; Westall, F.; Wheeler, R. M.; Zipfel, J.; Zorzano, M. P.
2018-04-01
Thorough characterization and evaluation of returned martian regolith and airfall samples are critical to understanding the potential health and engineering system hazards during future human exploration.
Fowler, Aja J; Evans, Patricia W; Etchegaray, Jason M; Ottenbacher, Allison; Arnold, Cody
2013-11-01
Our primary objective was to compare parents of infants cared for in newborn intensive care units (NICUs) and infants cared for in well-baby ("general") nurseries with regard to knowledge and practice of safe sleep practices/sudden infant death syndrome risk reduction measures and guidelines. Our secondary objective was to obtain qualitative data regarding reasons for noncompliance in both populations. Sixty participants (30 from each population) completed our survey measuring safe sleep knowledge and practice. Parents of NICU infants reported using 2 safe sleep practices-(a) always placing baby in crib to sleep and (b) always placing baby on back to sleep-significantly more frequently than parents of well infants. Additional findings and implications for future studies are discussed.
How well can future CMB missions constrain cosmic inflation?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martin, Jérôme; Vennin, Vincent; Ringeval, Christophe, E-mail: jmartin@iap.fr, E-mail: christophe.ringeval@uclouvain.be, E-mail: vennin@iap.fr
2014-10-01
We study how the next generation of Cosmic Microwave Background (CMB) measurement missions (such as EPIC, LiteBIRD, PRISM and COrE) will be able to constrain the inflationary landscape in the hardest to disambiguate situation in which inflation is simply described by single-field slow-roll scenarios. Considering the proposed PRISM and LiteBIRD satellite designs, we simulate mock data corresponding to five different fiducial models having values of the tensor-to-scalar ratio ranging from 10{sup -1} down to 10{sup -7}. We then compute the Bayesian evidences and complexities of all Encyclopædia Inflationaris models in order to assess the constraining power of PRISM alone andmore » LiteBIRD complemented with the Planck 2013 data. Within slow-roll inflation, both designs have comparable constraining power and can rule out about three quarters of the inflationary scenarios, compared to one third for Planck 2013 data alone. However, we also show that PRISM can constrain the scalar running and has the capability to detect a violation of slow roll at second order. Finally, our results suggest that describing an inflationary model by its potential shape only, without specifying a reheating temperature, will no longer be possible given the accuracy level reached by the future CMB missions.« less
NASA Astrophysics Data System (ADS)
Hatlinski, Grzegorz J.; Kornacki, Witold; Kukwa, Andrzej; Dobrowiecka, Bozena; Pikiel, Marek
2004-07-01
This paper proposes non-invasive solution to the problem of sleep apnea diagnosis especially in small children when sudden death syndrome is suspected. Plethysmographic wave analysis and digital signal processing algorithms are applied in order to find the effect invoked by respiratory movements of sleeping patients so as to diagnose the sleep apnea syndrome. The practical results of finding solution to problems mentioned above will be the possibility of algorithms implementation in a portable intelligent measurement system with a non-invasive monitoring of respiratory action. It works without any disturbances of sleep and respiratory movements especially in small children what could make possible in the future when continuous monitoring were applied to prevent sudden death syndrome occurrence.
Top 10 Research Questions Related to Preventing Sudden Death in Sport and Physical Activity.
Katch, Rachel K; Scarneo, Samantha E; Adams, William M; Armstrong, Lawrence E; Belval, Luke N; Stamm, Julie M; Casa, Douglas J
2017-09-01
Participation in organized sport and recreational activities presents an innate risk for serious morbidity and mortality. Although death during sport or physical activity has many causes, advancements in sports medicine and evidence-based standards of care have allowed clinicians to prevent, recognize, and treat potentially fatal injuries more effectively. With the continual progress of research and technology, current standards of care are evolving to enhance patient outcomes. In this article, we provided 10 key questions related to the leading causes and treatment of sudden death in sport and physical activity, where future research will support safer participation for athletes and recreational enthusiasts. The current evidence indicates that most deaths can be avoided when proper strategies are in place to prevent occurrence or provide optimal care.
Future Seismic Constraints on Mercury's Core Composition
NASA Astrophysics Data System (ADS)
Knibbe, J. S.; Luginbhuel, S. M.; Rivoldini, A.; Kono, Y.; Van Hoolst, T.; van Westrenen, W.
2018-05-01
The composition of Mercury's large core is strongly linked to the planet's origin and magnetic field generation. We present P-wave velocity measurements for liquid Fe-Si and Fe-S metals. A future seismic mission can constrain the core composition.
A 10-year Plan for Quality Living for People with Disabilities and Their Carers
ERIC Educational Resources Information Center
Craig, Jocelyn E.; Cartwright, Collen
2015-01-01
Background: The concerns of older carers of an adult with disabilities have been well documented. The sudden incapacity or death of the carer can result in a crisis response rather than a planned transition to a chosen sustainable alternative care arrangement for the person with disability. Building on previous "Futures Planning"…
2012-03-01
of gunfire interrupting the relative quiet of the countryside, or a sudden reduction in typical city noise, a change in the soundscape serves as an...in realistic soundscapes . Thereby, the Soldiers’ abilities to detect, discriminate, localize, and track can be accurately measured in a controlled
Popular Imagination and Identity Politics: Reading the Future in "Star Trek: The Next Generation."
ERIC Educational Resources Information Center
Ott, Brian L.; Aoki, Eric
2001-01-01
Analyzes the television series "Star Trek: The Next Generation." Theorizes the relationship between collective visions of the future and the identity politics of the present. Argues that "The Next Generation" invites audiences to participate in a shared sense of the future that constrains human agency and (re)produces the…
NASA Astrophysics Data System (ADS)
Hook, Stephen C.; Cobban, William A.
2016-12-01
Lopha staufferi (Bergquist, 1944) is a medium-sized, ribbed, Late Cretaceous oyster with a slightly curved axis and a zigzag commissure; it appears suddenly and conspicuously in upper Cenomanian rocks in the Western Interior Basin of the United States. At maturity, the ribs on both valves thicken into steep flanks that allow the oyster to increase interior volume without increasing its exterior footprint on the seafloor. Lopha staufferi is the first (earliest) ribbed oyster in the Late Cretaceous of the Western Interior, but has no ancestor in the basin. It disappears from the rock record as suddenly as it appeared, leaving no direct descendent in the basin. In the southern part of the basin where it is well constrained, L. staufferi is restricted stratigraphically to the upper Cenomanian Metoicoceras mosbyense Zone (= Dunveganoceras conditum Zone in the north). Lopha staufferi has an unusual paleogeographic distribution, occurring in only two, widely scattered areas in the basin. It has been found at several localities near the western shoreline of the Late Cretaceous Seaway in west-central New Mexico and adjacent Arizona, and in localities 1,900 km (1,200 mi) to the northeast near the eastern shoreline in northeastern Minnesota, but nowhere in between. In west-central New Mexico and adjacent Arizona, L. staufferi is a guide fossil to the Twowells Tongue of the Dakota Sandstone.
Relationship between emotional stress and cardiovascular events.
Senan, Mahavir; Petrosyan, A
2014-01-01
During last years the relationship has been found in between sudden cardiac death and autonomic disbalance of nervous system, which effect on baroreflector regulation of heart rhythm. The importance of heart rate in cardiovascular prognosis can be explained by its relationship with major pathophysiological determinants. We considered this fact as an actual problem and we performed our own study among 346 native Indians (260 males and 86 females), aged 41-54 years and employed by the Civil Service. They were consecutively examined between 1997 and 2004. Our large and long prospective study has disclosed a higher risk for sudden death for those apparently healthy individuals whose heart rate responses are exaggerated under mild emotional stress and below normal during peak exercise. This implies novel and simple ways for the early identification of subjects at increased future risk for sudden cardiac death. As well as we find out that autonomic disbalance is related with high risk of development of arrhythmias which is possible to find out exercise stress test. Individuals showing a high heart rate increase with mild emotional stress must be considered for additional investigations and for tailored preventive strategies aimed in first place to reduce the probability of ischemic heart disease.
Sudden cardiac death: a critical appraisal of the implantable cardioverter defibrillator.
Rajabali, A; Heist, E K
2014-04-01
Approximately 350,000 Americans still die of sudden cardiac death each year. This exceeds the number of patients who die annually from stroke, lung cancer, breast cancer and AIDS combined. This review aims to trace the history of implantable cardioverter defibrillators (ICD) with reference to landmark trials and their influence on the formulation of Medicare guidelines for ICD implantation criteria. This paper will also discuss the cost-effectiveness of ICDs and the quality of life after implantation. The reasons for the disparity between guidelines for implantation and actual clinical practice will be elucidated, with suggestions for improving overall clinical performance. The ICD has been shown to be cost-effective in reducing sudden cardiac death and all-cause mortality. However, the existing recommendations for ICD implantation have yet to translate completely into clinical practice. Barriers to implementation of existing guidelines include knowledge gaps in the referring physician practices, lack of validated screening tools to assess patient candidacy for the device and patient understanding of the need for the device. Future strategies to increase compliance with the existing guidelines and improve clinical performance are areas of potential research focus. © 2013 John Wiley & Sons Ltd.
Value, Cost, and Sharing: Open Issues in Constrained Clustering
NASA Technical Reports Server (NTRS)
Wagstaff, Kiri L.
2006-01-01
Clustering is an important tool for data mining, since it can identify major patterns or trends without any supervision (labeled data). Over the past five years, semi-supervised (constrained) clustering methods have become very popular. These methods began with incorporating pairwise constraints and have developed into more general methods that can learn appropriate distance metrics. However, several important open questions have arisen about which constraints are most useful, how they can be actively acquired, and when and how they should be propagated to neighboring points. This position paper describes these open questions and suggests future directions for constrained clustering research.
NASA Astrophysics Data System (ADS)
Renssen, Hans; Mairesse, Aurélien; Goosse, Hugues; Mathiot, Pierre; Heiri, Oliver; Roche, Didier M.; Nisancioglu, Kerim H.; Valdes, Paul J.
2016-04-01
The Younger Dryas cooling event disrupted the overall warming trend in the North Atlantic region during the last deglaciation. Climate change during the Younger Dryas was abrupt, and thus provides insights into the sensitivity of the climate system to perturbations. The sudden Younger Dryas cooling has traditionally been attributed to a shut-down of the Atlantic meridional overturning circulation by meltwater discharges. However, alternative explanations such as strong negative radiative forcing and a shift in atmospheric circulation have also been offered. In this study we investigate the importance of these different forcings in coupled climate model experiments constrained by data assimilation. We find that the Younger Dryas climate signal as registered in proxy evidence is best simulated using a combination of processes: a weakened Atlantic meridional overturning circulation, moderate negative radiative forcing and an altered atmospheric circulation. We conclude that none of the individual mechanisms alone provide a plausible explanation for the Younger Dryas cold period. We suggest that the triggers for abrupt climate changes like the Younger Dryas are more complex than suggested so far, and that studies on the response of the climate system to perturbations should account for this complexity. Reference: Renssen, H. et al. (2015) Multiple causes of the Younger Dryas cold period. Nature Geoscience 8, 946-949.
NASA Astrophysics Data System (ADS)
Gallet, Y.; Pavlov, V.; Shatsillo, A.; Hulot, G.
2015-12-01
Constraining the evolution in the geomagnetic reversal frequency over hundreds of million years is not a trivial matter. Beyond the fact that there are long periods without reversals, known as superchrons, and periods with many reversals, the way the reversal frequency changes through time during reversing periods is still debated. A smooth evolution or a succession of stationary segments have both been suggested to account for the geomagnetic polarity time scale since the Middle-Late Jurassic. Sudden changes from a reversing mode to a non-reversing mode of the geodynamo may also well have happened, the switch between the two modes having then possibly been controlled by the thermal conditions at the core-mantle boundary. There is, nevertheless, a growing set of magnetostratigraphic data, which could help decipher a proper interpretation of the reversal history, in particular in the early Paleozoic and even during the Precambrian. Although yielding a fragmentary record, these data reveal the occurrence of both additional superchrons and periods characterized by extremely high, not to say extraordinary, magnetic reversal frequencies. In this talk, we will present a synthesis of these data, mainly obtained from Siberia, and discuss their implication for the magnetic reversal behavior over the past billion years.
"Suddenly, I Had a Little Bit of Hope"
ERIC Educational Resources Information Center
Bryson, Lucy
2009-01-01
This article shares the story of Lucy Bryson, who was hooked on crack cocaine and heroin when she was 17, and was working the streets to fund her addiction. Her future looked bleak when she was imprisoned four years ago but a project that builds trust and responsibility in young people by teaching them to work with animals has transformed her…
ERIC Educational Resources Information Center
Conger, Rand D.; Elder, Glen H., Jr.
In Iowa in the 1980s, dreams of prosperity were suddenly replaced by economic nightmares as plummeting land values generated economic decline and dislocation in rural communities and individual lives. This book examines the experience of over 400 Iowa families who lived through the Great Farm Crisis and now face an uncertain future. Interviewed as…
The 12-lead electrocardiogram and risk of sudden death: current utility and future prospects.
Narayanan, Kumar; Chugh, Sumeet S
2015-10-01
More than 100 years after it was first invented, the 12-lead electrocardiogram (ECG) continues to occupy an important place in the diagnostic armamentarium of the practicing clinician. With the recognition of relatively rare but important clinical entities such as Wolff-Parkinson-White and the long QT syndrome, this clinical tool was firmly established as a test for assessing risk of sudden cardiac death (SCD). However, over the past two decades the role of the ECG in risk prediction for common forms of SCD, for example in patients with coronary artery disease, has been the focus of considerable investigation. Especially in light of the limitations of current risk stratification approaches, there is a renewed focus on this broadly available and relatively inexpensive test. Various abnormalities of depolarization and repolarization on the ECG have been linked to SCD risk; however, more focused work is needed before they can be deployed in the clinical arena. The present review summarizes the current knowledge on various ECG risk markers for prediction of SCD and discusses some future directions in this field. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.
Constraining dark sector perturbations I: cosmic shear and CMB lensing
NASA Astrophysics Data System (ADS)
Battye, Richard A.; Moss, Adam; Pearson, Jonathan A.
2015-04-01
We present current and future constraints on equations of state for dark sector perturbations. The equations of state considered are those corresponding to a generalized scalar field model and time-diffeomorphism invariant Script L(g) theories that are equivalent to models of a relativistic elastic medium and also Lorentz violating massive gravity. We develop a theoretical understanding of the observable impact of these models. In order to constrain these models we use CMB temperature data from Planck, BAO measurements, CMB lensing data from Planck and the South Pole Telescope, and weak galaxy lensing data from CFHTLenS. We find non-trivial exclusions on the range of parameters, although the data remains compatible with w=-1. We gauge how future experiments will help to constrain the parameters. This is done via a likelihood analysis for CMB experiments such as CoRE and PRISM, and tomographic galaxy weak lensing surveys, focussing in on the potential discriminatory power of Euclid on mildly non-linear scales.
Tests of gravity with future space-based experiments
NASA Astrophysics Data System (ADS)
Sakstein, Jeremy
2018-03-01
Future space-based tests of relativistic gravitation—laser ranging to Phobos, accelerometers in orbit, and optical networks surrounding Earth—will constrain the theory of gravity with unprecedented precision by testing the inverse-square law, the strong and weak equivalence principles, and the deflection and time delay of light by massive bodies. In this paper, we estimate the bounds that could be obtained on alternative gravity theories that use screening mechanisms to suppress deviations from general relativity in the Solar System: chameleon, symmetron, and Galileon models. We find that space-based tests of the parametrized post-Newtonian parameter γ will constrain chameleon and symmetron theories to new levels, and that tests of the inverse-square law using laser ranging to Phobos will provide the most stringent constraints on Galileon theories to date. We end by discussing the potential for constraining these theories using upcoming tests of the weak equivalence principle, and conclude that further theoretical modeling is required in order to fully utilize the data.
The sudden death and sudden birth of quantum discord.
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.
Dynamic facilitation explains 'democratic' particle motion of metabasin transitions
NASA Astrophysics Data System (ADS)
Hedges, Lester O.; Garrahan, Juan P.
2008-08-01
Transitions between metabasins in supercooled liquids seem to occur through rapid collective particle rearrangements. These events have been called 'democratic' as they appear homogeneous over a significant number of particles. This could suggest that 'democratic' rearrangements are fundamentally distinct to those leading to dynamic heterogeneity. Here we show, however, that this apparent homogeneous particle motion can be explained solely in terms of dynamic facilitation, and is therefore intriniscally heterogeneous. We do so by studying metabasin transitions in facilitated spin models and constrained lattice gases. We find that metabasin transitions occur through a sequence of locally facilitated events taking place over a relatively short time frame. When observed on small enough spatial windows these events appear sudden and homogeneous. Our results indicate that metabasin transitions, while apparently homogeneous and 'democratic', are yet another manifestation of dynamical heterogeneity in glass formers.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cowee, Misa; Liu, Kaijun; Friedel, Reinhard H.
2012-07-17
We summarize the scientific problem and work plan for the LANL LDRD-funded project to use a test particle code to study the sudden de-trapping of inner belt protons and possible cross-L transport of debris ions after a high altitude nuclear explosion (HANE). We also discuss future application of the code for other HANE-related problems.
H.L. Spaulding; L.K. Rieske
2011-01-01
The highly pathogenic Phytophthora ramorum, causal organism of sudden oak death (SOD), is established in forests of the Pacific Northwest (USA) and is threatening invasion of other regions. Given the breadth of its host range, with dozens of asymptomatic ornamental hosts and with oaks, Quercus spp., in the red oak (Erythrobalanus) subgenus particularly susceptible, we...
J.K. Gilless; J. Tack; A. Peterson Zwane
2006-01-01
While there is a great deal of scientific uncertainty about the nature and control of Phytophthora ramorum, there is growing concern that its economic costs will be significant. Indeed the repercussions at the nursery level of a positive test for the presence of P. ramorum may include severely impacted current and future cash flows...
A real-time extension of density matrix embedding theory for non-equilibrium electron dynamics
NASA Astrophysics Data System (ADS)
Kretchmer, Joshua S.; Chan, Garnet Kin-Lic
2018-02-01
We introduce real-time density matrix embedding theory (DMET), a dynamical quantum embedding theory for computing non-equilibrium electron dynamics in strongly correlated systems. As in the previously developed static DMET, real-time DMET partitions the system into an impurity corresponding to the region of interest coupled to the surrounding environment, which is efficiently represented by a quantum bath of the same size as the impurity. In this work, we focus on a simplified single-impurity time-dependent formulation as a first step toward a multi-impurity theory. The equations of motion of the coupled impurity and bath embedding problem are derived using the time-dependent variational principle. The accuracy of real-time DMET is compared to that of time-dependent complete active space self-consistent field (TD-CASSCF) theory and time-dependent Hartree-Fock (TDHF) theory for a variety of quantum quenches in the single impurity Anderson model (SIAM), in which the Hamiltonian is suddenly changed (quenched) to induce a non-equilibrium state. Real-time DMET shows a marked improvement over the mean-field TDHF, converging to the exact answer even in the non-trivial Kondo regime of the SIAM. However, as expected from analogous behavior in static DMET, the constrained structure of the real-time DMET wavefunction leads to a slower convergence with respect to active space size, in the single-impurity formulation, relative to TD-CASSCF. Our initial results suggest that real-time DMET provides a promising framework to simulate non-equilibrium electron dynamics in which strong electron correlation plays an important role, and lays the groundwork for future multi-impurity formulations.
A real-time extension of density matrix embedding theory for non-equilibrium electron dynamics.
Kretchmer, Joshua S; Chan, Garnet Kin-Lic
2018-02-07
We introduce real-time density matrix embedding theory (DMET), a dynamical quantum embedding theory for computing non-equilibrium electron dynamics in strongly correlated systems. As in the previously developed static DMET, real-time DMET partitions the system into an impurity corresponding to the region of interest coupled to the surrounding environment, which is efficiently represented by a quantum bath of the same size as the impurity. In this work, we focus on a simplified single-impurity time-dependent formulation as a first step toward a multi-impurity theory. The equations of motion of the coupled impurity and bath embedding problem are derived using the time-dependent variational principle. The accuracy of real-time DMET is compared to that of time-dependent complete active space self-consistent field (TD-CASSCF) theory and time-dependent Hartree-Fock (TDHF) theory for a variety of quantum quenches in the single impurity Anderson model (SIAM), in which the Hamiltonian is suddenly changed (quenched) to induce a non-equilibrium state. Real-time DMET shows a marked improvement over the mean-field TDHF, converging to the exact answer even in the non-trivial Kondo regime of the SIAM. However, as expected from analogous behavior in static DMET, the constrained structure of the real-time DMET wavefunction leads to a slower convergence with respect to active space size, in the single-impurity formulation, relative to TD-CASSCF. Our initial results suggest that real-time DMET provides a promising framework to simulate non-equilibrium electron dynamics in which strong electron correlation plays an important role, and lays the groundwork for future multi-impurity formulations.
The case for extraterrestrial causes of extinction
NASA Technical Reports Server (NTRS)
Raup, D. M.
1989-01-01
The dramatic increase in our knowledge of large-body impacts that have occurred in Earth's history has led to strong arguments for the plausibility of meteorite impact as a cause of extinction. Proof of causation is often hampered, however, by our inability to demonstrate the synchronism of specific impacts and extinctions. A central problem is range truncation: the last reported occurrences of fossil taxa generally underestimate the true times of extinction. Range truncation, because of gaps in sedimentation, lack of preservation, or lack of discovery, can make sudden extinctions appear gradual and gradual extinctions appear sudden. Also, stepwise extinction may appear as an artefact of range truncation. These effects are demonstrated by experiments performed on data from field collections of Cretaceous ammonities from Zumaya (Spain). The challenge for future research is to develop a new calculus for treating biostratigraphic data so that fossils can provide more accurate assessments of the timing of extinctions.
Idriss, Salim F; Berger, Stuart; Harmon, Kimberly G; Kindman, Allen; Kleiman, Robert; Lopez-Anderson, Martha; Molossi, Silvana; Saarel, Tess Elizabeth; Strnadova, Colette; Todaro, Thomas; Shinagawa, Kaori; Morrow, Valarie; Krucoff, Mitchell; Vetter, Victoria; Wright, Theressa J
2017-08-01
This White Paper, prepared by members of the Cardiac Safety Research Consortium, discusses important issues regarding sudden cardiac death in the young (SCDY), a problem that does not discriminate by gender, race, ethnicity, education, socioeconomic level, or athletic status. The occurrence of SCDY has devastating impact on families and communities. Sudden cardiac death in the young is a matter of national and international public health, and its prevention has generated deep interest from multiple stakeholders, including families who have lost children, advocacy groups, academicians, regulators, and the medical industry. To promote scientific and clinical discussion of SCDY prevention and to germinate future initiatives to move this field forward, a Cardiac Safety Research Consortium-sponsored Think Tank was held on February 21, 2015 at the US Food and Drug Administration's White Oak facilities, Silver Spring, MD. The ultimate goal of the Think Tank was to spark initiatives that lead to the development of a rational, reliable, and sustainable national health care resource focused on SCDY prevention. This article provides a detailed summary of discussions at the Think Tank and descriptions of related multistakeholder initiatives now underway: it does not represent regulatory guidance. Copyright © 2017 Elsevier Inc. All rights reserved.
Sudden gains in cognitive therapy and interpersonal therapy for social anxiety disorder.
Bohn, Christiane; Aderka, Idan M; Schreiber, Franziska; Stangier, Ulrich; Hofmann, Stefan G
2013-02-01
The present study examined the effects of sudden gains on treatment outcome in a randomized controlled trial including individual cognitive therapy (CT) and interpersonal therapy (IPT) for social anxiety disorder (SAD). Participants were 67 individuals with SAD who received 16 treatment sessions. Symptom severity at each session was assessed using the Social Phobia Weekly Summary Scale (Clark et al., 2003). Results indicate that 22.4% of participants experienced a sudden gain during treatment. Individuals with sudden gains had significantly lower social anxiety symptoms at post-treatment and follow-up compared to individuals without sudden gains. Sudden gains in CT and IPT had similar magnitudes, frequencies, and timings. However, sudden gains resulted in lower levels of post-treatment symptoms in CT compared to IPT. Cognitive changes did not precede sudden gains, but sudden gains resulted in cognitive changes. Sudden gains in CT and IPT for SAD are predictive of long-term outcome. In addition, the effect of sudden gains may be greater in CT compared to IPT.
Analysis and Hindcast Experiments of the 2009 Sudden Stratospheric Warming in WACCMX+DART
NASA Astrophysics Data System (ADS)
Pedatella, N. M.; Liu, H.-L.; Marsh, D. R.; Raeder, K.; Anderson, J. L.; Chau, J. L.; Goncharenko, L. P.; Siddiqui, T. A.
2018-04-01
The ability to perform data assimilation in the Whole Atmosphere Community Climate Model eXtended version (WACCMX) is implemented using the Data Assimilation Research Testbed (DART) ensemble adjustment Kalman filter. Results are presented demonstrating that WACCMX+DART analysis fields reproduce the middle and upper atmosphere variability during the 2009 major sudden stratospheric warming (SSW) event. Compared to specified dynamics WACCMX, which constrains the meteorology by nudging toward an external reanalysis, the large-scale dynamical variability of the stratosphere, mesosphere, and lower thermosphere is improved in WACCMX+DART. This leads to WACCMX+DART better representing the downward transport of chemical species from the mesosphere into the stratosphere following the SSW. WACCMX+DART also reproduces most aspects of the observed variability in ionosphere total electron content and equatorial vertical plasma drift during the SSW. Hindcast experiments initialized on 5, 10, 15, 20, and 25 January are used to assess the middle and upper atmosphere predictability in WACCMX+DART. A SSW, along with the associated middle and upper atmosphere variability, is initially predicted in the hindcast initialized on 15 January, which is ˜10 days prior to the warming. However, it is not until the hindcast initialized on 20 January that a major SSW is forecast to occur. The hindcast experiments reveal that dominant features of the total electron content can be forecasted ˜10-20 days in advance. This demonstrates that whole atmosphere models that properly account for variability in lower atmosphere forcing can potentially extend the ionosphere-thermosphere forecast range.
Precision constraints on the top-quark effective field theory at future lepton colliders
NASA Astrophysics Data System (ADS)
Durieux, G.
We examine the constraints that future lepton colliders would impose on the effective field theory describing modifications of top-quark interactions beyond the standard model, through measurements of the $e^+e^-\\to bW^+\\:\\bar bW^-$ process. Statistically optimal observables are exploited to constrain simultaneously and efficiently all relevant operators. Their constraining power is sufficient for quadratic effective-field-theory contributions to have negligible impact on limits which are therefore basis independent. This is contrasted with the measurements of cross sections and forward-backward asymmetries. An overall measure of constraints strength, the global determinant parameter, is used to determine which run parameters impose the strongest restriction on the multidimensional effective-field-theory parameter space.
Rosenberry, D.O.; Glaser, P.H.; Siegel, D.I.
2006-01-01
Recent research indicates that accumulation and release of biogenic gas from northern peatlands may substantially affect future climate. Sudden release of free-phase gas bubbles into the atmosphere may preclude the conversion of methane to carbon dioxide in the uppermost oxic layer of the peat, resulting in greater contribution of methane to the atmosphere than is currently estimated. The hydrology of these peatlands also affects and is affected by this process, especially when gas is released suddenly and episodically. Indirect hydrological evidence indicates that ebullitive gas releases are relatively frequent in some peatlands and time-averaged rates may be significantly greater than diffusive releases. Estimates of free-phase gas contained in peat have ranged from 0 to nearly 20% of the peat volume. Abrupt changes in the volume of gas may alter hydraulic gradients and movement of water and solutes in peat, which in turn could alter composition and fluxes of the gas. Peat surfaces also move vertically and horizontally in response to accumulation and release of free-phase gas. Future research should address the distribution, temporal variability, and relative significance of ebullition in peatlands and the consequent hydrological responses to these gas-emission events. Copyright ?? 2006 John Wiley & Sons, Ltd.
Constraining the noncommutative spectral action via astrophysical observations.
Nelson, William; Ochoa, Joseph; Sakellariadou, Mairi
2010-09-03
The noncommutative spectral action extends our familiar notion of commutative spaces, using the data encoded in a spectral triple on an almost commutative space. Varying a rather simple action, one can derive all of the standard model of particle physics in this setting, in addition to a modified version of Einstein-Hilbert gravity. In this Letter we use observations of pulsar timings, assuming that no deviation from general relativity has been observed, to constrain the gravitational sector of this theory. While the bounds on the coupling constants remain rather weak, they are comparable to existing bounds on deviations from general relativity in other settings and are likely to be further constrained by future observations.
NASA Astrophysics Data System (ADS)
Gügercinoğlu, Erbil
2017-12-01
Glitches, sudden spin-up of pulsars with subsequent recovery, provide us with a unique opportunity to investigate various physical processes, including the crust-core coupling, distribution of reservoir angular momentum within different internal layers, spin-up in neutral and charged superfluids and constraining the equation of state of the neutron star (NS) matter. In this work, depending on the dynamic interaction between the vortex lines and the nuclei in the inner crust, and between the vortex lines and the magnetic flux tubes in the outer core, various types of relaxation behavior are obtained and confronted with the observations. It is shown that the glitches have strong potential to deduce information about the cooling behavior and interior magnetic field configuration of NSs. Some implications of the relative importance of the external spin-down torques and the superfluid internal torques for recently observed unusual glitches are also discussed.
Do object refixations during scene viewing indicate rehearsal in visual working memory?
Zelinsky, Gregory J; Loschky, Lester C; Dickinson, Christopher A
2011-05-01
Do refixations serve a rehearsal function in visual working memory (VWM)? We analyzed refixations from observers freely viewing multiobject scenes. An eyetracker was used to limit the viewing of a scene to a specified number of objects fixated after the target (intervening objects), followed by a four-alternative forced choice recognition test. Results showed that the probability of target refixation increased with the number of fixated intervening objects, and these refixations produced a 16% accuracy benefit over the first five intervening-object conditions. Additionally, refixations most frequently occurred after fixations on only one to two other objects, regardless of the intervening-object condition. These behaviors could not be explained by random or minimally constrained computational models; a VWM component was required to completely describe these data. We explain these findings in terms of a monitor-refixate rehearsal system: The activations of object representations in VWM are monitored, with refixations occurring when these activations decrease suddenly.
Frequency transitions in odor-evoked neural oscillations
Ito, Iori; Bazhenov, Maxim; Ong, Rose Chik-ying; Raman, Baranidharan; Stopfer, Mark
2009-01-01
Summary In many species sensory stimuli elicit the oscillatory synchronization of groups of neurons. What determines the properties of these oscillations? In the olfactory system of the moth we found that odors elicited oscillatory synchronization through a neural mechanism like that described in locust and Drosophila. During responses to long odor pulses, oscillations suddenly slowed as net olfactory receptor neuron (ORN) output decreased; thus, stimulus intensity appeared to determine oscillation frequency. However, changing the concentration of the odor had little effect upon oscillatory frequency. Our recordings in vivo and computational models based on these results suggested the main effect of increasing odor concentration was to recruit additional, less well-tuned ORNs whose firing rates were tightly constrained by adaptation and saturation. Thus, in the periphery, concentration is encoded mainly by the size of the responsive ORN population, and oscillation frequency is set by the adaptation and saturation of this response. PMID:20005825
Frequency transitions in odor-evoked neural oscillations.
Ito, Iori; Bazhenov, Maxim; Ong, Rose Chik-ying; Raman, Baranidharan; Stopfer, Mark
2009-12-10
In many species, sensory stimuli elicit the oscillatory synchronization of groups of neurons. What determines the properties of these oscillations? In the olfactory system of the moth, we found that odors elicited oscillatory synchronization through a neural mechanism like that described in locust and Drosophila. During responses to long odor pulses, oscillations suddenly slowed as net olfactory receptor neuron (ORN) output decreased; thus, stimulus intensity appeared to determine oscillation frequency. However, changing the concentration of the odor had little effect upon oscillatory frequency. Our recordings in vivo and computational models based on these results suggested that the main effect of increasing odor concentration was to recruit additional, less well-tuned ORNs whose firing rates were tightly constrained by adaptation and saturation. Thus, in the periphery, concentration is encoded mainly by the size of the responsive ORN population, and oscillation frequency is set by the adaptation and saturation of this response.
Cardiovascular benefits of omega-3 fatty acids.
von Schacky, Clemens; Harris, William S
2007-01-15
Cardiac societies recommend the intake of 1 g/day of the two omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for cardiovascular disease prevention, treatment after a myocardial infarction, prevention of sudden death, and secondary prevention of cardiovascular disease. These recommendations are based on a body of scientific evidence that encompasses literally thousands of publications. Of four large scale intervention studies three also support the recommendations of these cardiac societies. One methodologically questionable study with a negative result led a Cochrane meta-analysis to a null conclusion. This null conclusion, however, has not swayed the recommendations of the cardiac societies mentioned, and has been refuted with good reason by scientific societies. Based on the scientific evidence just mentioned, we propose a new risk factor to be considered for sudden cardiac death, the omega-3 index. It is measured in red blood cells, and is expressed as a percentage of EPA + DHA of total fatty acids. An omega-3 index of >8% is associated with 90% less risk for sudden cardiac death, as compared to an omega-3 index of <4%. The omega-3 index as a risk factor for sudden cardiac death has striking similarities to LDL as a risk factor for coronary artery disease. Moreover, the omega-3 index reflects the omega-3 fatty acid status of a given individual (analogous to HbA1c reflecting glucose homeostasis). The omega-3 index can therefore be used as a goal for treatment with EPA and DHA. As is the case now for LDL, in the future, the cardiac societies might very well recommend treatment with EPA and DHA to become goal oriented (e.g. an omega-3 index>8%).
Weighting climate model projections using observational constraints.
Gillett, Nathan P
2015-11-13
Projected climate change integrates the net response to multiple climate feedbacks. Whereas existing long-term climate change projections are typically based on unweighted individual climate model simulations, as observed climate change intensifies it is increasingly becoming possible to constrain the net response to feedbacks and hence projected warming directly from observed climate change. One approach scales simulated future warming based on a fit to observations over the historical period, but this approach is only accurate for near-term projections and for scenarios of continuously increasing radiative forcing. For this reason, the recent Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR5) included such observationally constrained projections in its assessment of warming to 2035, but used raw model projections of longer term warming to 2100. Here a simple approach to weighting model projections based on an observational constraint is proposed which does not assume a linear relationship between past and future changes. This approach is used to weight model projections of warming in 2081-2100 relative to 1986-2005 under the Representative Concentration Pathway 4.5 forcing scenario, based on an observationally constrained estimate of the Transient Climate Response derived from a detection and attribution analysis. The resulting observationally constrained 5-95% warming range of 0.8-2.5 K is somewhat lower than the unweighted range of 1.1-2.6 K reported in the IPCC AR5. © 2015 The Authors.
De Sá Teixeira, Nuno Alexandre
2016-09-01
The memory for the final position of a moving object which suddenly disappears has been found to be displaced forward, in the direction of motion, and downwards, in the direction of gravity. These phenomena were coined, respectively, Representational Momentum and Representational Gravity. Although both these and similar effects have been systematically linked with the functioning of internal representations of physical variables (e.g. momentum and gravity), serious doubts have been raised for a cognitively based interpretation, favouring instead a major role of oculomotor and perceptual factors which, more often than not, were left uncontrolled and even ignored. The present work aims to determine the degree to which Representational Momentum and Representational Gravity are epiphenomenal to smooth pursuit eye movements. Observers were required to indicate the offset locations of targets moving along systematically varied directions after a variable imposed retention interval. Each participant completed the task twice, varying the eye movements' instructions: gaze was either constrained or left free to track the targets. A Fourier decomposition analysis of the localization responses was used to disentangle both phenomena. The results show unambiguously that constraining eye movements significantly eliminates the harmonic components which index Representational Momentum, but have no effect on Representational Gravity or its time course. The found outcomes offer promising prospects for the study of the visual representation of gravity and its neurological substrates.
NASA Astrophysics Data System (ADS)
Shan, Chuan-Jia; Chen, Tao; Liu, Ji-Bing; Cheng, Wei-Wen; Liu, Tang-Kun; Huang, Yan-Xia; Li, Hong
2010-06-01
In this paper, we investigate the dynamical behaviour of entanglement in terms of concurrence in a bipartite system subjected to an external magnetic field under the action of dissipative environments in the extended Werner-like initial state. The interesting phenomenon of entanglement sudden death as well as sudden birth appears during the evolution process. We analyse in detail the effect of the purity of the initial entangled state of two qubits via Heisenberg XY interaction on the apparition time of entanglement sudden death and entanglement sudden birth. Furthermore, the conditions on the conversion of entanglement sudden death and entanglement sudden birth can be generalized when the initial entangled state is not pure. In particular, a critical purity of the initial mixed entangled state exists, above which entanglement sudden birth vanishes while entanglement sudden death appears. It is also noticed that stable entanglement, which is independent of different initial states of the qubits (pure or mixed state), occurs even in the presence of decoherence. These results arising from the combination of the extended Werner-like initial state and dissipative environments suggest an approach to control and enhance the entanglement even after purity induced sudden birth, death and revival.
Using dry and wet year hydroclimatic extremes to guide future hydrologic projections
NASA Astrophysics Data System (ADS)
Oni, Stephen; Futter, Martyn; Ledesma, Jose; Teutschbein, Claudia; Buttle, Jim; Laudon, Hjalmar
2016-07-01
There are growing numbers of studies on climate change impacts on forest hydrology, but limited attempts have been made to use current hydroclimatic variabilities to constrain projections of future climatic conditions. Here we used historical wet and dry years as a proxy for expected future extreme conditions in a boreal catchment. We showed that runoff could be underestimated by at least 35 % when dry year parameterizations were used for wet year conditions. Uncertainty analysis showed that behavioural parameter sets from wet and dry years separated mainly on precipitation-related parameters and to a lesser extent on parameters related to landscape processes, while uncertainties inherent in climate models (as opposed to differences in calibration or performance metrics) appeared to drive the overall uncertainty in runoff projections under dry and wet hydroclimatic conditions. Hydrologic model calibration for climate impact studies could be based on years that closely approximate anticipated conditions to better constrain uncertainty in projecting extreme conditions in boreal and temperate regions.
Unveiling the nucleon tensor charge at Jefferson Lab: A study of the SoLID case
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, Zhihong; Sato, Nobuo; Allada, Kalyan
2017-01-27
Here, future experiments at the Jefferson Lab 12 GeV upgrade, in particular, the Solenoidal Large Intensity Device (SoLID), aim at a very precise data set in the region where the partonic structure of the nucleon is dominated by the valence quarks. One of the main goals is to constrain the transversity quark distributions. We apply recent theoretical advances of the global QCD extraction of the transversity distributions to study the impact of future experimental data from the SoLID. Especially, we develop a model-independent method based on the hessian matrix analysis that allows to estimate the uncertainties of the transversity quarkmore » distributions and their tensor charge contributions extracted from the pseudo-data for the SoLID. Both u and d-quark transversity distributions are shown to be very well constrained in the kinematical region of the future experiments with the proton and the effective neutron targets.« less
Sudden gains in exposure therapy for obsessive-compulsive disorder.
Collins, Lindsey M; Coles, Meredith E
2017-06-01
Prior research in the treatment of depression and anxiety has demonstrated that a sudden reduction in symptoms between two consecutive sessions (sudden gain) is related to lower post-treatment symptom severity (e.g. Hofmann, Schulz, Meuret, Moscovitch, & Suvak, 2006; Tang & DeRubeis, 1999). However, only one study has examined sudden gains in the treatment of obsessive compulsive disorder (OCD). In that study, one-third of the patients with OCD experienced a sudden gain (Aderka et al., 2012). Further, patients who had a sudden gain had lower clinician-rated OCD symptom severity post-treatment (Aderka et al., 2012). In replication, the current study examined the frequency, characteristics, and clinical impact of sudden gains in 27 OCD patients during exposure and response prevention (ERP) therapy. Fifty two percent of patients experienced a sudden gain. The mean magnitude of a sudden gain represented, on average, 61.4% of total symptom reduction. Following treatment, individuals who had experienced a sudden gain were rated as less severe on the clinical global impression scale, but they did not experience a greater reduction in OCD symptoms (pre-to post-treatment) than those without a sudden gain. None of the pre-treatment characteristics tested were found to significantly predict whether a patient would have a sudden gain. Additional research examining predictors of, and patterns of, change in OCD symptoms is warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.
The in situ transverse lamina strength of composite laminates
NASA Technical Reports Server (NTRS)
Flaggs, D. L.
1983-01-01
The objective of the work reported in this presentation is to determine the in situ transverse strength of a lamina within a composite laminate. From a fracture mechanics standpoint, in situ strength may be viewed as constrained cracking that has been shown to be a function of both lamina thickness and the stiffness of adjacent plies that serve to constrain the cracking process. From an engineering point of view, however, constrained cracking can be perceived as an apparent increase in lamina strength. With the growing need to design more highly loaded composite structures, the concept of in situ strength may prove to be a viable means of increasing the design allowables of current and future composite material systems. A simplified one dimensional analytical model is presented that is used to predict the strain at onset of transverse cracking. While it is accurate only for the most constrained cases, the model is important in that the predicted failure strain is seen to be a function of a lamina's thickness d and of the extensional stiffness bE theta of the adjacent laminae that constrain crack propagation in the 90 deg laminae.
Constrained evolution in numerical relativity
NASA Astrophysics Data System (ADS)
Anderson, Matthew William
The strongest potential source of gravitational radiation for current and future detectors is the merger of binary black holes. Full numerical simulation of such mergers can provide realistic signal predictions and enhance the probability of detection. Numerical simulation of the Einstein equations, however, is fraught with difficulty. Stability even in static test cases of single black holes has proven elusive. Common to unstable simulations is the growth of constraint violations. This work examines the effect of controlling the growth of constraint violations by solving the constraints periodically during a simulation, an approach called constrained evolution. The effects of constrained evolution are contrasted with the results of unconstrained evolution, evolution where the constraints are not solved during the course of a simulation. Two different formulations of the Einstein equations are examined: the standard ADM formulation and the generalized Frittelli-Reula formulation. In most cases constrained evolution vastly improves the stability of a simulation at minimal computational cost when compared with unconstrained evolution. However, in the more demanding test cases examined, constrained evolution fails to produce simulations with long-term stability in spite of producing improvements in simulation lifetime when compared with unconstrained evolution. Constrained evolution is also examined in conjunction with a wide variety of promising numerical techniques, including mesh refinement and overlapping Cartesian and spherical computational grids. Constrained evolution in boosted black hole spacetimes is investigated using overlapping grids. Constrained evolution proves to be central to the host of innovations required in carrying out such intensive simulations.
NASA Astrophysics Data System (ADS)
Smith, Brent M.; Windhorst, Rogier A.; Jansen, Rolf A.; Cohen, Seth H.; Jiang, Linhua; Dijkstra, Mark; Koekemoer, Anton M.; Bielby, Richard; Inoue, Akio K.; MacKenty, John W.; O’Connell, Robert W.; Silk, Joseph I.
2018-02-01
We present observations of escaping Lyman Continuum (LyC) radiation from 34 massive star-forming galaxies (SFGs) and 12 weak AGN with reliably measured spectroscopic redshifts at z≃ 2.3{--}4.1. We analyzed Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) mosaics of the Early Release Science (ERS) field in three UVIS filters to sample the rest-frame LyC over this redshift range. With our best current assessment of the WFC3 systematics, we provide 1σ upper limits for the average LyC emission of galaxies at < z> = 2.35, 2.75, and 3.60 to ∼28.5, 28.1, and 30.7 mag in image stacks of 11–15 galaxies in the WFC3/UVIS F225W, F275W, and F336W, respectively. The LyC flux of weak AGN at < z> = 2.62 and 3.32 are detected at 28.3 and 27.4 mag with S/Ns of ∼2.7 and 2.5 in F275W and F336W for stacks of 7 and 3 AGN, respectively, while AGN at < z> = 2.37 are constrained to ≳27.9 mag at 1σ in a stack of 2 AGN. The stacked AGN LyC light profiles are flatter than their corresponding non-ionizing UV continuum profiles out to radii of r≲ 0\\buildrel{\\prime\\prime}\\over{.} 9, which may indicate a radial dependence of porosity in the ISM. With synthetic stellar SEDs fit to UV continuum measurements longward of {{Ly}}α and IGM transmission models, we constrain the absolute LyC escape fractions to {f}{esc}{abs}≃ {22}-22+44% at < z> = 2.35 and ≲55% at < z> = 2.75 and 3.60, respectively. All available data for galaxies, including published work, suggests a more sudden increase of {f}{esc} with redshift at z≃ 2. Dust accumulating in (massive) galaxies over cosmic time correlates with increased H I column density, which may lead to reducing {f}{esc} more suddenly at z≲ 2. This may suggest that SFGs collectively contributed to maintaining cosmic reionization at redshifts z≳ 2{--}4, while AGN likely dominated reionization at z≲ 2.
NASA Astrophysics Data System (ADS)
Sox, Leda
The Earth's middle atmosphere (10-110 km) has long been a region in which measurement techniques are limited. Many ground-based and remote sensing satellite instruments have been developed over the past several decades, which strive to provide good coverage of this region. However, each of the different techniques has its own measurement limitations in the extent of its coverage in altitude, time, or global-scale. In order for researchers to trace geophysical dynamics and phenomena across the three regions in the middle atmosphere, measurements from many instruments often have to be spliced together. Rayleigh-scatter lidar is a ground-based remote sensing technique that has been used to acquire relative density and absolute temperature measurements throughout the 35-90 km region at several sites for the past four decades. Rayleigh lidars have a unique advantage over many other middle-atmosphere instruments in that their measurements do not have a theoretical limit to their altitude coverage. Their upper altitude limits are only constrained by technological advances in instrumentation and their lower limits are only constrained by the presence of aerosols (below about 35 km). However, Mie and Raman scatter detectors can be added to extend their measurements down to ground level. The Rayleigh lidar on the campus of Utah State University has recently been upgraded in such a way as to extend its upper altitude limit 25 km higher, into the lower thermosphere. The first year (2014-2015) of data acquired with this new system has been analyzed to obtain temperatures in the 70-115 km region. Numerical experiments were carried out that showed it was possible to compensate for changing atmospheric composition above 90 km with minimal effects on the derived Rayleigh temperatures. These new temperatures were in good agreement with temperatures from the previous version of the system and well-established results of the thermal structure in the mesosphere-lower thermosphere region. Subsequently, the first comparison between collocated Rayleigh and Na lidars, covering identical time periods and altitude ranges, was conducted. An example of the scientific results that can be mined from long-term Rayleigh lidar observations is also given. It establishes the behavior of the midlatitude mesosphere during sudden stratospheric warming events.
Taxation of exhaustible resources. [Monograph
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dasgupta, P.; Heal, G.; Stiglitz, J.
1980-01-01
This paper analyzes the effect of taxation on the intertemporal allocation of an exhaustible resource. A general framework within which a large variety of taxes can be analyzed is developed and then applied to a number of specific taxes. It is shown that there exists a pattern of taxation which can generate essentially any desired pattern of resource usage. Many tax policies, however, have effects markedly different both from the effects that these policies would have in the case of produced commodities and from those which they are designed (or widely thought) to have. For instance, if extraction costs aremore » zero, a depletion allowance at a constant rate (widely thought to encourage the extraction of resources) has absolutely no effect; its gradual removal (usually thought to be preferable to a sudden removal) leads to faster rates of depletion (and lower prices) now, but higher prices in the future; which its sudden and unanticipated removal has absolutely no distortionary effect on the pattern of extraction. More generally, it is shown that the effects of tax structure on the patterns of extraction are critically dependent on expectations concerning future taxation. The changes in tax structure that have occurred in the past fifty years are of the kind that, if they were anticipated, (or if similar further changes are expected to occur in the future) lead to excessively fast exploitation of natural resources. However, if it is believed that current tax policies (including rates) will persist indefinitely, the current tax structure would lead to excessive conservationism. Thus, whether in fact current tax policies have lead to excessive conservationism is a moot question.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lanza, Mathieu; Lique, François, E-mail: francois.lique@univ-lehavre.fr
The determination of hyperfine structure resolved excitation cross sections and rate coefficients due to H{sub 2} collisions is required to interpret astronomical spectra. In this paper, we present several theoretical approaches to compute these data. An almost exact recoupling approach and approximate sudden methods are presented. We apply these different approaches to the HCl–H{sub 2} collisional system in order to evaluate their respective accuracy. HCl–H{sub 2} hyperfine structure resolved cross sections and rate coefficients are then computed using recoupling and approximate sudden methods. As expected, the approximate sudden approaches are more accurate when the collision energy increases and the resultsmore » suggest that these approaches work better for para-H{sub 2} than for ortho-H{sub 2} colliding partner. For the first time, we present HCl–H{sub 2} hyperfine structure resolved rate coefficients, computed here for temperatures ranging from 5 to 300 K. The usual Δj{sub 1} = ΔF{sub 1} propensity rules are observed for the hyperfine transitions. The new rate coefficients will significantly help the interpretation of interstellar HCl emission lines observed with current and future telescopes. We expect that these new data will allow a better determination of the HCl abundance in the interstellar medium, that is crucial to understand the interstellar chlorine chemistry.« less
Theodor Hellbrügge: 85 years of age – Ad multos transannos, sanos, fortunatos et beatos
Halberg, Franz; Cornélissen, Germaine; Katinas, George; Schwartzkopff, Othild; Johnson, Dana
2005-01-01
We honor Theo Hellbrügge's acclaimed endeavors in the rehabilitation, or rather the prehabilitation of handicapped children. So far, he has focused on obvious handicaps, and we trust that he will include concern for everybody's silent handicaps in the future by screening for abnormal variability inside the physiological range. Therein, we introduce cis- and trans-years, components of transdisciplinary spectra that are novel for biology and also in part for physics. These components have periods, respectively, shorter and longer than the calendar year, with a counterpart in magnetoperiodism. Transyears characterize indices of geomagnetic activity and the solar wind's speed and proton density. They are detected, alone or together with circannuals, in physiology as well as in pathology, as illustrated for sudden cardiac death and myocardial infarction, a finding calling for similar studies in sudden infant death syndrome (SIDS). As transyears can beat with circannuals, and depend on local factors, their systematic mapping in space and time by transdisciplinary chronomics may serve a better understanding of their putative influence upon the circadian system. Longitudinal monitoring of blood pressure and heart rate detects chronome alterations underlying cardiovascular disease risk, such as that of myocardial infarction and sudden cardiac death. The challenge is to intervene in a timely fashion, preferably at birth, an opportunity for pediatricians in Theo Hellbrügge's footsteps. PMID:15748294
Alattar, A; Maffulli, N
2015-01-01
Objective: To review the available evidence establishing the validity of adding electrocardiogram to the preparticipation cardiac screening in athletes. Data Sources: MEDLINE and CINAHL databases were searched. Additional references from the bibliographies of retrieved articles were also reviewed and experts in the area were contacted. Selection Criteria: Only original research articles seeking to establish the use of electrocardiography followed by second line investigations in athletes under 36 years of age were reviewed. Search Result and Quality Assessment: The initial literature search identified 226 papers. Of these, 16 original articles (all type II evidence—population-based clinical studies) met the selection criteria and directly related to the use of electrocardiography in athletes cardiac screening. The methodological qualities of included studies were assessed using the Downs and Black checklist. Conclusion: Screening with electrocardiography represents best clinical practice to prevent or reduce the risk of sudden cardiac death in athletes. It significantly improves the sensitivity of history and physical examination alone; it has reasonable specificity and excellent negative predictive value; and it is cost-effective. Future studies must be large, multicentre, multination, prospective trials powered to determine how different screening options affect the incidence of sudden cardiac death. Efforts should also be targeted toward secondary prevention of sudden cardiac death with pitch side cardiac resuscitation and the immediate use of defibrillator. PMID:25674543
A "Wear and Tear" Hypothesis to Explain Sudden Infant Death Syndrome.
Elhaik, Eran
2016-01-01
Sudden infant death syndrome (SIDS) is the leading cause of death among USA infants under 1 year of age accounting for ~2,700 deaths per year. Although formally SIDS dates back at least 2,000 years and was even mentioned in the Hebrew Bible (Kings 3:19), its etiology remains unexplained prompting the CDC to initiate a sudden unexpected infant death case registry in 2010. Due to their total dependence, the ability of the infant to allostatically regulate stressors and stress responses shaped by genetic and environmental factors is severely constrained. We propose that SIDS is the result of cumulative painful, stressful, or traumatic exposures that begin in utero and tax neonatal regulatory systems incompatible with allostasis. We also identify several putative biochemical mechanisms involved in SIDS. We argue that the important characteristics of SIDS, namely male predominance (60:40), the significantly different SIDS rate among USA Hispanics (80% lower) compared to whites, 50% of cases occurring between 7.6 and 17.6 weeks after birth with only 10% after 24.7 weeks, and seasonal variation with most cases occurring during winter, are all associated with common environmental stressors, such as neonatal circumcision and seasonal illnesses. We predict that neonatal circumcision is associated with hypersensitivity to pain and decreased heart rate variability, which increase the risk for SIDS. We also predict that neonatal male circumcision will account for the SIDS gender bias and that groups that practice high male circumcision rates, such as USA whites, will have higher SIDS rates compared to groups with lower circumcision rates. SIDS rates will also be higher in USA states where Medicaid covers circumcision and lower among people that do not practice neonatal circumcision and/or cannot afford to pay for circumcision. We last predict that winter-born premature infants who are circumcised will be at higher risk of SIDS compared to infants who experienced fewer nociceptive exposures. All these predictions are testable experimentally using animal models or cohort studies in humans. Our hypothesis provides new insights into novel risk factors for SIDS that can reduce its risk by modifying current infant care practices to reduce nociceptive exposures.
Sudden gains in group cognitive-behavioral therapy for panic disorder.
Clerkin, Elise M; Teachman, Bethany A; Smith-Janik, Shannan B
2008-11-01
The current study investigates sudden gains (rapid symptom reduction) in group cognitive-behavioral therapy for panic disorder. Sudden gains occurring after session 2 of treatment predicted overall symptom reduction at treatment termination and some changes in cognitive biases. Meanwhile, sudden gains occurring immediately following session 1 were not associated with symptom reduction or cognitive change. Together, this research points to the importance of examining sudden gains across the entire span of treatment, as well as the potential role of sudden gains in recovery from panic disorder.
Sudden Gains in Group Cognitive-Behavioral Therapy for Panic Disorder
Clerkin, Elise M.; Teachman, Bethany A.; Smith-Janik, Shannan B.
2008-01-01
The current study investigates sudden gains (rapid symptom reduction) in group cognitive-behavioral therapy for panic disorder. Sudden gains occurring after session 2 of treatment predicted overall symptom reduction at treatment termination and some changes in cognitive biases. Meanwhile, sudden gains occurring immediately following session 1 were not associated with symptom reduction or cognitive change. Together, this research points to the importance of examining sudden gains across the entire span of treatment, as well as the potential role of sudden gains in recovery from panic disorder. PMID:18804199
Sudden Death in Young People--Heart Problems Often Blamed
Sudden death in young people: Heart problems often blamed Sudden death in young people is rare, but those at ... causes and treatments. By Mayo Clinic Staff Sudden death in people younger than 35, often due to ...
Geomagnetic sudden impulses and storm sudden commencements - A note on terminology
NASA Technical Reports Server (NTRS)
Joselyn, J. A.; Tsurutani, B. T.
1990-01-01
The definitions of and distinctions between storm sudden commencements (SSCs) and geomagnetic sudden impulses (SIs) are examined and present definitions of SIs and SSCs are modernized. Quantitative definitions of the two terms are recommended.
Portfolio management under sudden changes in volatility and heterogeneous investment horizons
NASA Astrophysics Data System (ADS)
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.
Pinto, J V; Ramani, K; Neelagaru, S; Kown, M; Gheorghiade, M
1997-01-01
Amiodarone appears to reduce sudden death in patients with left ventricular dysfunction resulting from an acute MI or a primary dilated cardiomyopathy, particularly if complex ventricular arrhythmias are present. Amiodarone's beneficial effect on mortality in these patients could be unrelated to its antiarrhythmic effects. Multiple factors could account for the improvement in mortality such as the drug's antiischemic effects, neuromodulating effects, its effect on left ventricular function and on heart rate. Moreover, patients with LV dysfunction who have survived an episode of sudden death would potentially benefit from amiodarone therapy. Future trials are needed to determine the precise subsets(s) of patients who would benefit from the drug and the most efficacious dosing regimen for the drug. Based on available data, amiodarone is the only antiarrhythmic agent which has not been shown to increase mortality in patients with chronic heart failure.
Chronobiology in aortic diseases - "is this really a random phenomenon?".
Manfredini, Roberto; Fabbian, Fabio; Manfredini, Fabio; Salmi, Raffaella; Gallerani, Massimo; Bossone, Eduardo
2013-01-01
Although acute aortic rupture or dissection is relatively uncommon, it ranks in third position among necropsy-confirmed causes of out-of-hospital sudden death in the general population. Similar to other acute cardiovascular events (e.g., acute myocardial infarction, sudden death, stroke, and pulmonary embolism) there is a growing body of evidence regarding temporal patterns in onset, characterized by circadian, seasonal and weekly variations for aortic aneurysms. On one hand, it is possible that these cardiovascular diseases share common underlying pathophysiologic mechanisms, e.g., increase in blood pressure, heart rate, sympathetic activity, basal vascular tone, vasoconstrictive hormones, and prothrombotic tendency. On the other hand, the possibility exists that the connecting link is an internal disruption (dyssynchrony) of some molecular mechanisms intrinsic to the peripheral biological clock (that of cardiomyocyte is the most widely investigated). Such disruption may contribute to cardiovascular disease and biological rhythms - an intriguing hypothesis for future research. Copyright © 2013 Elsevier Inc. All rights reserved.
Using Paleo-climate Comparisons to Constrain Future Projections in CMIP5
NASA Technical Reports Server (NTRS)
Schmidt, G. A.; Annan, J D.; Bartlein, P. J.; Cook, B. I.; Guilyardi, E.; Hargreaves, J. C.; Harrison, S. P.; Kageyama, M.; LeGrande, A. N..; Konecky, B.;
2013-01-01
We present a description of the theoretical framework and best practice for using the paleo-climate model component of the Coupled Model Intercomparison Project (Phase 5) (CMIP5) to constrain future projections of climate using the same models. The constraints arise from measures of skill in hindcasting paleo-climate changes from the present over 3 periods: the Last Glacial Maximum (LGM) (21 thousand years before present, ka), the mid-Holocene (MH) (6 ka) and the Last Millennium (LM) (8501850 CE). The skill measures may be used to validate robust patterns of climate change across scenarios or to distinguish between models that have differing outcomes in future scenarios. We find that the multi-model ensemble of paleo-simulations is adequate for addressing at least some of these issues. For example, selected benchmarks for the LGM and MH are correlated to the rank of future projections of precipitationtemperature or sea ice extent to indicate that models that produce the best agreement with paleoclimate information give demonstrably different future results than the rest of the models. We also find that some comparisons, for instance associated with model variability, are strongly dependent on uncertain forcing timeseries, or show time dependent behaviour, making direct inferences for the future problematic. Overall, we demonstrate that there is a strong potential for the paleo-climate simulations to help inform the future projections and urge all the modeling groups to complete this subset of the CMIP5 runs.
2012-05-17
and the Northern Sea Route, extraction of potential oil and gas resources, and expanded fishing and tourism .‖ 6 The Arctic‘s vast natural resources...sudden and substantial increase in commercial shipping, marine tourism , and large passenger vessels in the Arctic poses significant challenges to the...security,‖ Huebert states that, ―Canada, Denmark, Norway, Russia and the United States have all either begun to rebuild their Arctic capabilities
On meeting capital requirements with a chance-constrained optimization model.
Atta Mills, Ebenezer Fiifi Emire; Yu, Bo; Gu, Lanlan
2016-01-01
This paper deals with a capital to risk asset ratio chance-constrained optimization model in the presence of loans, treasury bill, fixed assets and non-interest earning assets. To model the dynamics of loans, we introduce a modified CreditMetrics approach. This leads to development of a deterministic convex counterpart of capital to risk asset ratio chance constraint. We pursue the scope of analyzing our model under the worst-case scenario i.e. loan default. The theoretical model is analyzed by applying numerical procedures, in order to administer valuable insights from a financial outlook. Our results suggest that, our capital to risk asset ratio chance-constrained optimization model guarantees banks of meeting capital requirements of Basel III with a likelihood of 95 % irrespective of changes in future market value of assets.
A review of patients who suddenly deteriorate in the presence of paramedics.
Boyle, Malcolm J; Smith, Erin C; Archer, Frank
2008-07-26
The report of the Ministerial Review of Trauma and Emergency Services in Victoria, Australia, recommended that paramedics be permitted to divert to the closest hospital in incidences of life threatening situations prior to and during transport. An audit of patients that suddenly deteriorated in paramedic care was recommended by the Ministerial Review. The objective of the study was to identify the number and outcome of patients who suddenly deteriorated in the presence of paramedics. A retrospective cohort study of trauma patients who suddenly deteriorated in the presence of paramedics during 2002. As there was no standard definition, sudden deterioration was defined using a predetermined set of physiological criteria. Patient care record data of patients who suddenly deteriorated were compared with the State Trauma Registry to determine those who sustained hospital defined major trauma. Patient care records where hospital bypass was undertaken were identified and analysed. Ethics committee approval was obtained. There were 2,893 patients that suddenly deteriorated according to predefined criteria. 2,687 (5.1% of the total trauma patients for 2002) were suitable for further analysis. The majority of patients had a sudden decrease in BP (n = 2,463) with 4.3% having hospital defined major trauma. For patients with a sudden decrease in conscious state or a total GCS score of less than 13 (n = 77), 37.7% had hospital defined major trauma; and a sudden increase/decrease in pulse rate and sudden decrease in BP (n = 65), 26.2% had hospital defined major trauma. Only 28 documented incidents of hospital bypass were identified. This study suggests that the incidents of patients suddenly deteriorating in the presence of paramedics are low and the incidence of hospital bypass is not well documented.
Sudden gains in exposure-focused cognitive-behavioral group therapy for panic disorder.
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.
Constraining modified gravitational theories by weak lensing with Euclid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martinelli, Matteo; Calabrese, Erminia; De Bernardis, Francesco
2011-01-15
Future proposed satellite missions such as Euclid can offer the opportunity to test general relativity on cosmic scales through mapping of the galaxy weak-lensing signal. In this paper we forecast the ability of these experiments to constrain modified gravity scenarios such as those predicted by scalar-tensor and f(R) theories. We find that Euclid will improve constraints expected from the Planck satellite on these modified theories of gravity by 2 orders of magnitude. We discuss parameter degeneracies and the possible biases introduced by modifications to gravity.
Solution techniques for transient stability-constrained optimal power flow – Part II
Geng, Guangchao; Abhyankar, Shrirang; Wang, Xiaoyu; ...
2017-06-28
Transient stability-constrained optimal power flow is an important emerging problem with power systems pushed to the limits for economic benefits, dense and larger interconnected systems, and reduced inertia due to expected proliferation of renewable energy resources. In this study, two more approaches: single machine equivalent and computational intelligence are presented. Also discussed are various application areas, and future directions in this research area. In conclusion, a comprehensive resource for the available literature, publicly available test systems, and relevant numerical libraries is also provided.
Constraining properties of disintegrating exoplanets
NASA Astrophysics Data System (ADS)
Veras, D.; Carter, P. J.; Leinhardt, Z. M.; Gänsicke, B. T.
2017-09-01
Evaporating and disintegrating planets provide unique insights into chemical makeup and physical constraints. The striking variability, depth (˜10 - 60%) and shape of the photometric transit curves due to the disintegrating minor planet orbiting white dwarf WD 1145+017 has galvanised the post-main- sequence exoplanetary science community. We have performed the first tidal disruption simulations of this planetary object, and have succeeded in constraining its mass, density, eccentricity and physical nature. We illustrate how our simulations can bound these properties, and be used in the future for other exoplanetary systems.
Solution techniques for transient stability-constrained optimal power flow – Part II
DOE Office of Scientific and Technical Information (OSTI.GOV)
Geng, Guangchao; Abhyankar, Shrirang; Wang, Xiaoyu
Transient stability-constrained optimal power flow is an important emerging problem with power systems pushed to the limits for economic benefits, dense and larger interconnected systems, and reduced inertia due to expected proliferation of renewable energy resources. In this study, two more approaches: single machine equivalent and computational intelligence are presented. Also discussed are various application areas, and future directions in this research area. In conclusion, a comprehensive resource for the available literature, publicly available test systems, and relevant numerical libraries is also provided.
Iloprost-induced sudden hearing loss.
Dursun, E; Dogru, S; Cincik, H; Cekin, E; Gungor, A; Poyrazoglu, E
2007-06-01
We report a patient who developed sudden, bilateral, sensorineural hearing loss during therapeutic use of iloprost for Raynaud's phenomenon. The sudden hearing loss was attributed to iloprost use and completely reversed in eight days with conservative therapy. Iloprost may be a potentially ototoxic drug, causing sudden hearing loss.
Political economies and environmental futures for the sharing economy.
Frenken, Koen
2017-06-13
The sudden rise of the sharing economy has sparked an intense public debate about its definition, its effects and its future regulation. Here, I attempt to provide analytical guidance by defining the sharing economy as the practice that consumers grant each other temporary access to their under-utilized physical assets. Using this definition, the rise of the sharing economy can be understood as occurring at the intersection of three salient economic trends: peer-to-peer exchange, access over ownership and circular business models. I shortly discuss some of the environmental impacts of online sharing platforms and then articulate three possible futures of the sharing economy: a capitalist future cumulating in monopolistic super-platforms allowing for seamless services, a state-led future that shifts taxation from labour to capital and redistributes the gains of sharing from winners to losers, and a citizen-led future based on cooperatively owned platforms under democratic control. The nature and size of the social and environmental impacts are expected to differ greatly in each of the three scenarios.This article is part of the themed issue 'Material demand reduction'. © 2017 The Authors.
Political economies and environmental futures for the sharing economy
NASA Astrophysics Data System (ADS)
Frenken, Koen
2017-05-01
The sudden rise of the sharing economy has sparked an intense public debate about its definition, its effects and its future regulation. Here, I attempt to provide analytical guidance by defining the sharing economy as the practice that consumers grant each other temporary access to their under-utilized physical assets. Using this definition, the rise of the sharing economy can be understood as occurring at the intersection of three salient economic trends: peer-to-peer exchange, access over ownership and circular business models. I shortly discuss some of the environmental impacts of online sharing platforms and then articulate three possible futures of the sharing economy: a capitalist future cumulating in monopolistic super-platforms allowing for seamless services, a state-led future that shifts taxation from labour to capital and redistributes the gains of sharing from winners to losers, and a citizen-led future based on cooperatively owned platforms under democratic control. The nature and size of the social and environmental impacts are expected to differ greatly in each of the three scenarios. This article is part of the themed issue 'Material demand reduction'.
Political economies and environmental futures for the sharing economy
2017-01-01
The sudden rise of the sharing economy has sparked an intense public debate about its definition, its effects and its future regulation. Here, I attempt to provide analytical guidance by defining the sharing economy as the practice that consumers grant each other temporary access to their under-utilized physical assets. Using this definition, the rise of the sharing economy can be understood as occurring at the intersection of three salient economic trends: peer-to-peer exchange, access over ownership and circular business models. I shortly discuss some of the environmental impacts of online sharing platforms and then articulate three possible futures of the sharing economy: a capitalist future cumulating in monopolistic super-platforms allowing for seamless services, a state-led future that shifts taxation from labour to capital and redistributes the gains of sharing from winners to losers, and a citizen-led future based on cooperatively owned platforms under democratic control. The nature and size of the social and environmental impacts are expected to differ greatly in each of the three scenarios. This article is part of the themed issue ‘Material demand reduction’. PMID:28461431
Cosmology with an interacting van der Waals fluid
NASA Astrophysics Data System (ADS)
Elizalde, E.; Khurshudyan, M.
A model for the late-time accelerated expansion of the Universe is considered where a van der Waals fluid interacting with matter plays the role of dark energy. The transition towards this phase in the cosmic evolution history is discussed in detail and, moreover, a complete classification of the future finite-time singularities is obtained for six different possible forms of the nongravitational interaction between dark energy (the van der Waals fluid) and dark matter. This study shows, in particular, that a Universe with a noninteracting three-parameter van der Waals fluid can evolve into a Universe characterized by a type IV (generalized sudden) singularity. On the other hand, for certain values of the parameters, exit from the accelerated expanding phase is possible in the near future, what means that the expansion of the Universe in the future could become decelerated - to our knowledge, this interesting situation is not commonplace in the literature. On the other hand, our study shows that space can be divided into different regions. For some of them, in particular, the nongravitational interactions Q = 3Hbρde, Q = 3Hbρdm and Q = 3Hb(ρde + ρde) may completely suppress future finite-time singularity formation, for sufficiently high values of b. On the other hand, for some other regions of the parameter space, the mentioned interactions would not affect the singularity type, namely the type IV singularity generated in the case of the noninteracting model would be preserved. A similar conclusion has been archived for the cases of Q = 3bHρdeρdm/(ρde + ρdm), Q = 3bHρdm2/(ρ de + ρdm) and Q = 3bHρde2/(ρ de + ρdm) nongravitational interactions, with only one difference: the Q = 3bHρdm2/(ρ de + ρdm) interaction will change the type IV singularity of the noninteracting model into a type II (the sudden) singularity.
Proceedings of the Sudden Oak Death Fourth Science Symposium
Susan J. Frankel; John T. Kliejunas; Katharine M. Palmieri
2010-01-01
The Sudden Oak Death Fourth Science Symposium provided a forum for current research on sudden oak death, caused by the exotic, quarantine pathogen, Phytophthora ramorum. Ninety submissions describing papers or posters on the following sudden oak death/P. ramorum topics are included: biology, genetics, nursery and wildland...
Proceedings of the sudden oak death third science symposium
Susan J. Frankel; John T. Kliejunas; Katharine M. Palmieri
2008-01-01
The Sudden Oak Death Third Science Symposium provided a forum for current research on sudden oak death, caused by the exotic, quarantine pathogen, Phytophthora ramorum. One hundred and seventeen submissions describing papers and posters on the following sudden oak death/ P. ramorum topics are included: biology, genetics, nursery,...
Proceedings of the sudden oak death sixth science symposium
Susan J. Frankel; Katharine M. Harrell
2017-01-01
The Sudden Oak Death Sixth Science Symposium provided a forum for current research on sudden oak death, caused by the exotic quarantine pathogen Phytophthora ramorum. More than 50 submissions describing papers or posters on the following sudden oak death/P. ramorum topics are included: biology, genetics, nursery and wildland...
Sudden Death in Sleep of Laotian-Hmong Refugees in Thailand: A Case-Control Study.
ERIC Educational Resources Information Center
Munger, Ronald G.
1987-01-01
Surveillance for sudden deaths conducted among Laotian-Hmong refugees in Thailand revealed associations between sudden death in sleep and membership in the Green-Hmong subgroup, a family history of sudden death, and previous non-fatal sleep disturbances. Most victims are young men. (PS)
Africa and the Paris Agreement
NASA Astrophysics Data System (ADS)
Kruger, Andries C.
2018-05-01
The African continent is one of the most vulnerable regions to future climate change. Research now demonstrates that constraining anthropogenic warming to 1.5 °C instead of 2 °C will significantly lower the risk of heatwaves to inhabitants.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Craig, Nathaniel; Gu, Jiayin; Liu, Zhen
Here, we study angular observables in themore » $$ {e}^{+}{e}^{-}\\to ZH\\to {\\ell}^{+}{\\ell}^{-}b\\overline{b} $$ channel at future circular e$$^{+}$$ e$$^{-}$$ colliders such as CEPC and FCC-ee. Taking into account the impact of realistic cut acceptance and detector effects, we forecast the precision of six angular asymmetries at CEPC (FCC-ee) with center-of-mass energy $$ \\sqrt{s}=240 $$ GeV and 5 (30) ab$$^{-1}$$ integrated luminosity. We then determine the projected sensitivity to a range of operators relevant for he Higgs-strahlung process in the dimension-6 Higgs EFT. Our results show that angular observables provide complementary sensitivity to rate measurements when constraining various tensor structures arising from new physics. We further find that angular asymmetries provide a novel means of both probing BSM corrections to the HZγ coupling and constraining the “blind spot” in indirect limits on supersymmetric scalar top partners.« less
Craig, Nathaniel; Gu, Jiayin; Liu, Zhen; ...
2016-03-09
Here, we study angular observables in themore » $$ {e}^{+}{e}^{-}\\to ZH\\to {\\ell}^{+}{\\ell}^{-}b\\overline{b} $$ channel at future circular e$$^{+}$$ e$$^{-}$$ colliders such as CEPC and FCC-ee. Taking into account the impact of realistic cut acceptance and detector effects, we forecast the precision of six angular asymmetries at CEPC (FCC-ee) with center-of-mass energy $$ \\sqrt{s}=240 $$ GeV and 5 (30) ab$$^{-1}$$ integrated luminosity. We then determine the projected sensitivity to a range of operators relevant for he Higgs-strahlung process in the dimension-6 Higgs EFT. Our results show that angular observables provide complementary sensitivity to rate measurements when constraining various tensor structures arising from new physics. We further find that angular asymmetries provide a novel means of both probing BSM corrections to the HZγ coupling and constraining the “blind spot” in indirect limits on supersymmetric scalar top partners.« less
Planck and the reionization of the universe
NASA Astrophysics Data System (ADS)
Crill, Brendan
2016-03-01
Planck is the third-generation satellite aimed at measuring the cosmic microwave background, a relic of the hot big bang. Planck's temperature and polarization maps of the millimeter-wave sky have constrained parameters of the standard lambda-CDM model of cosmology to incredible precision, and have provided constraints on inflation in the very early universe. Planck's all-sky survey of polarization in seven frequency bands can remove contamination from nearby Galactic emission and constrain the optical depth of the reionized Universe, giving insight into the properties of the earliest star formation. The final 2016 data release from Planck will include a refined optical depth measurement using the full sensitivity of both the High Frequency and Low Frequency instruments. I present the status of the reionization measurement and discuss future prospects for further measurements of the early Universe with the CMB from Planck and future space and suborbital platforms.
Al-Khatib, Sana M; Sanders, Gillian D; Bigger, J Thomas; Buxton, Alfred E; Califf, Robert M; Carlson, Mark; Curtis, Anne; Curtis, Jeptha; Fain, Eric; Gersh, Bernard J; Gold, Michael R; Haghighi-Mood, Ali; Hammill, Stephen C; Healey, Jeff; Hlatky, Mark; Hohnloser, Stefan; Kim, Raymond J; Lee, Kerry; Mark, Daniel; Mianulli, Marcus; Mitchell, Brent; Prystowsky, Eric N; Smith, Joseph; Steinhaus, David; Zareba, Wojciech
2007-06-01
Accurate and timely prediction of sudden cardiac death (SCD) is a necessary prerequisite for effective prevention and therapy. Although the largest number of SCD events occurs in patients without overt heart disease, there are currently no tests that are of proven predictive value in this population. Efforts in risk stratification for SCD have focused primarily on predicting SCD in patients with known structural heart disease. Despite the ubiquity of tests that have been purported to predict SCD vulnerability in such patients, there is little consensus on which test, in addition to the left ventricular ejection fraction, should be used to determine which patients will benefit from an implantable cardioverter defibrillator. On July 20 and 21, 2006, a group of experts representing clinical cardiology, cardiac electrophysiology, biostatistics, economics, and health policy were joined by representatives of the US Food and Drug administration, Centers for Medicare Services, Agency for Health Research and Quality, the Heart Rhythm Society, and the device and pharmaceutical industry for a round table meeting to review current data on strategies of risk stratification for SCD, to explore methods to translate these strategies into practice and policy, and to identify areas that need to be addressed by future research studies. The meeting was organized by the Duke Center for the Prevention of SCD at the Duke Clinical Research Institute and was funded by industry participants. This article summarizes the presentations and discussions that occurred at that meeting.
Testing inflation and curvaton scenarios with CMB distortions
NASA Astrophysics Data System (ADS)
Clesse, Sébastien; Garbrecht, Björn; Zhu, Yi
2014-10-01
Prior to recombination, Silk damping causes the dissipation of energy from acoustic waves into the monopole of the Cosmic Microwave Background (CMB), resulting in spectral distortions. These can be used to probe the primordial scalar power spectrum on smaller scales than it is possible with CMB anisotropies. An enhancement of power on these scales is nevertheless required for the resulting distortions to be detectable by future experiments like PIXIE. In this paper, we examine all 49 single-field inflation models listed by Martin et al. in the Encyclopaedia Inflationaris [1] and find that only one of these may lead to a detectable level of distortions in a tuned region of its parameter space, namely the original hybrid model. Three effective multi-field scenarios are also studied: with softly and suddenly turning trajectories, and with a mild waterfall trajectory. Softly turning trajectories do not induce distortions at any detectable level, whereas a sudden turn in the field space or a mild waterfall trajectory predicts a peak (plus damped oscillations in the sudden turn case) in the scalar power spectrum, which can lead to an observable amount of CMB distortions. Finally, another scenario leading to potentially detectable distortions involves a curvaton whose blue spectrum is subdominant on CMB angular scales and overtakes the inflaton spectrum on smaller scales. In this case however, we show that the bounds from ultra compact minihaloes are not satisfied. Expectations for an ultimate PRISM-class experiment characterized by an improvement in sensitivity by a factor of ten are discussed for some models.
Sudden Gains During Therapy of Social Phobia
Hofmann, Stefan G.; Schulz, Stefan M.; Meuret, Alicia E.; Moscovitch, David A.; Suvak, Michael
2007-01-01
The present study investigated the phenomenon of sudden gains in 107 participants with social phobia (social anxiety disorder) who received either cognitive–behavioral group therapy or exposure group therapy without explicit cognitive interventions, which primarily used public speaking situations as exposure tasks. Twenty-two out of 967 session-to-session intervals met criteria for sudden gains, which most frequently occurred in Session 5. Individuals with sudden gains showed similar improvements in the 2 treatment groups. Although cognitive–behavioral therapy was associated with more cognitive changes than exposure therapy, cognitive changes did not precede sudden gains. In general, the results of this study question the clinical significance of sudden gains in social phobia treatment. PMID:16881776
Zhao, Peng; Wang, Ji-Gang; Gao, Peng; Li, Xia; Brewer, Rubell
2016-01-01
The aim of this study is to identify and subclassify sudden natural death (sudden death from natural diseases) cases in Seychelles. A total of 484 sudden natural death cases with autopsy at the Clinical Pathology Laboratory, Victoria Hospital, Seychelles between 1997 through 2012 were retrospectively reviewed. Among them, 363 cases (75%) were male and 121 (25%) were female. The most frequent sudden deaths were attributed to cardiovascular diseases (78.5%), and then followed by infectious diseases (9.9%), and gastrointestinal diseases (9.1%). This is the largest population-based study on sudden natural deaths in Seychelles. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Dynamic Parameters of the 2015 Nepal Gorkha Mw7.8 Earthquake Constrained by Multi-observations
NASA Astrophysics Data System (ADS)
Weng, H.; Yang, H.
2017-12-01
Dynamic rupture model can provide much detailed insights into rupture physics that is capable of assessing future seismic risk. Many studies have attempted to constrain the slip-weakening distance, an important parameter controlling friction behavior of rock, for several earthquakes based on dynamic models, kinematic models, and direct estimations from near-field ground motion. However, large uncertainties of the values of the slip-weakening distance still remain, mostly because of the intrinsic trade-offs between the slip-weakening distance and fault strength. Here we use a spontaneously dynamic rupture model to constrain the frictional parameters of the 25 April 2015 Mw7.8 Nepal earthquake, by combining with multiple seismic observations such as high-rate cGPS data, strong motion data, and kinematic source models. With numerous tests we find the trade-off patterns of final slip, rupture speed, static GPS ground displacements, and dynamic ground waveforms are quite different. Combining all the seismic constraints we can conclude a robust solution without a substantial trade-off of average slip-weakening distance, 0.6 m, in contrast to previous kinematical estimation of 5 m. To our best knowledge, this is the first time to robustly determine the slip-weakening distance on seismogenic fault from seismic observations. The well-constrained frictional parameters may be used for future dynamic models to assess seismic hazard, such as estimating the peak ground acceleration (PGA) etc. Similar approach could also be conducted for other great earthquakes, enabling broad estimations of the dynamic parameters in global perspectives that can better reveal the intrinsic physics of earthquakes.
Chroni, M; Prappa, E; Kokkevi, I
2018-04-01
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.
Proceedings of the sudden oak death second science symposium: the state of our knowledge
Susan J. Frankel; Patrick J. Shea; Michael I. Haverty
2006-01-01
The Sudden Oak Death Second Science Symposium provided a forum for current research on sudden oak death, caused by the exotic, quarantine pathogen, Phytophthora ramorum. Ninety papers and forty-six posters on the following sudden oak death/P. ramorum topics are included: biology, genetics, nursery and wildland management,...
Sudden Gains in Cognitive Therapy of Depression and Depression Relapse/Recurrence
ERIC Educational Resources Information Center
Tang, Tony Z.; DeRubeis, Robert J.; Hollon, Steven D.; Amsterdam, Jay; Shelton, Richard
2007-01-01
Cognitive therapy (CT) may have significant advantages over antidepressants in preventing depression relapses. Many CT patients experience sudden gains: large symptom improvement in 1 between-session interval. Past studies have associated CT sudden gains with in-session cognitive changes but not with life events. This study examined sudden gains…
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 <18 at listing undergoing 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 < 0.0001), United Network of Organ Sharing (UNOS) status 2 at 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.
Haloperidol and sudden cardiac death in dementia: autopsy findings in psychiatric inpatients.
Ifteni, Petru; Grudnikoff, Eugene; Koppel, Jeremy; Kremen, Neil; Correll, Christoph U; Kane, John M; Manu, Peter
2015-12-01
Treatment with haloperidol has been shown, in studies using death certificates and prescription files, to be associated with an excess of sudden cardiac deaths, and regulatory warnings highlight this risk in patients with dementia. We used autopsy findings to determine whether the rate of sudden cardiac death is greater in cases of unexpected deaths of patients with dementia treated with haloperidol. From 1989 through 2013, 1219 patients with a primary diagnosis of dementia with behavioral disturbance were admitted to a psychiatric hospital, and 65 (5.3%) died suddenly. Sixty-five patients (5.3%) died unexpectedly. Complete post-mortem examinations after the sudden death were performed in 55 (84.6%) patients. Twenty-seven of the autopsied cases (49.1%) had been treated with haloperidol orally (2.2 mg ± 2.1 mg/day), the only antipsychotic used in this cohort. Univariable comparisons and multivariable regression analyses compared the groups of patients with or without sudden cardiac death. The leading causes of death were sudden cardiac death (32.7%), myocardial infarction (25.5% of patients), pneumonia (23.6%), and stroke (10.9%). Patients with sudden cardiac death and those with anatomically established cause of death were similar regarding the use of haloperidol (p = 0.5). Sudden cardiac death patients were more likely to suffer from Alzheimer's dementia (p = 0.027) and to have a past history of heart disease (p = 0.0094), and less likely to have been treated with a mood stabilizer (p = 0.024), but none of these variables were independent predictors of sudden cardiac death. Autopsy data suggest that oral haloperidol is not associated with increased risk of sudden cardiac death in psychiatric inpatients with dementia. Copyright © 2015 John Wiley & Sons, Ltd.
Future sea level rise constrained by observations and long-term commitment.
Mengel, Matthias; Levermann, Anders; Frieler, Katja; Robinson, Alexander; Marzeion, Ben; Winkelmann, Ricarda
2016-03-08
Sea level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of sea level rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, sea level is still expected to rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main sea level rise contributions with their last century's observed contribution to constrain projections of future sea level rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century sea level rise. We project anthropogenic sea level rise of 28-56 cm, 37-77 cm, and 57-131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total sea level rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The "constrained extrapolation" approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections.
Future sea level rise constrained by observations and long-term commitment
Mengel, Matthias; Levermann, Anders; Frieler, Katja; Robinson, Alexander; Marzeion, Ben; Winkelmann, Ricarda
2016-01-01
Sea level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of sea level rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, sea level is still expected to rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main sea level rise contributions with their last century's observed contribution to constrain projections of future sea level rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century sea level rise. We project anthropogenic sea level rise of 28–56 cm, 37–77 cm, and 57–131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total sea level rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The “constrained extrapolation” approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections. PMID:26903648
Entanglement of two qubits coupled to an XY spin chain: Role of energy current
NASA Astrophysics Data System (ADS)
Liu, Ben-Qiong; Shao, Bin; Zou, Jian
2009-12-01
We investigate the entanglement dynamics of a two-qubit system which interacts with a Heisenberg XY spin chain constrained to carry an energy current. We show an explicit connection between the decoherence factor and entanglement, and numerically and analytically study the dynamical process of entanglement in both weak- and strong-coupling cases for two initial states, the general pure state and the mixed Werner state. We provide results that the entanglement evolution depends not only on the energy current, the anisotropy parameter and the system-environment couplings but also on the size of degrees of freedom of environment. In particular, our results imply that entanglement will be strongly suppressed by the introduction of energy current on the environmental spin chain in the weak-coupling region while it is not sensitive to the energy current in the strong-coupling region. We also observe the sudden death of entanglement in the system and show how the energy current affects the phenomenon.
NASA Technical Reports Server (NTRS)
Manney, Gloria L.; Krueger, Kirstin; Pawson, Steven; Schwartz, Michael J.; Daffer, William H.; Livesey, Nathaniel J.; Remsberg, Ellis E.; Mlynczak, Martin G.; Russell, James M., III; Waters, Joe W.
2007-01-01
Microwave Limb Sounder and Sounding of the Atmosphere with Broadband Emission Radiometry data show the polar stratopause, usually higher than and separated from that at midlatitudes, dropping from <55-60 to near 30 km, and cooling dramatically in January 2006 during a major stratospheric sudden warming (SSW). After a nearly isothermal period, a cool stratopause reforms near 75 km in early February, then drops to <55 km and warms. The stratopause is separated in longitude as well as latitude, with lowest temperatures in the transition regions between higher and lower stratopauses. Operational assimilated meteorological analyses, which are not constrained by data at stratopause altitude, do not capture a secondary temperature maximum that overlies the stratopause or the very high stratopause that reforms after the SSW; they underestimate the stratopause altitude variation during the SSW. High-quality daily satellite temperature measurements are invaluable in improving our understanding of stratopause evolution and its representation in models and assimilation systems.
A New Target Object for Constraining Annihilating Dark Matter
NASA Astrophysics Data System (ADS)
Chan, Man Ho
2017-07-01
In the past decade, gamma-ray observations and radio observations of our Milky Way and the Milky Way dwarf spheroidal satellite galaxies put very strong constraints on annihilation cross sections of dark matter. In this paper, we suggest a new target object (NGC 2976) that can be used for constraining annihilating dark matter. The radio and X-ray data of NGC 2976 can put very tight constraints on the leptophilic channels of dark matter annihilation. The lower limits of dark matter mass annihilating via {e}+{e}-, {μ }+{μ }-, and {τ }+{τ }- channels are 200 GeV, 130 GeV, and 110 GeV, respectively, with the canonical thermal relic cross section. We suggest that this kind of large nearby dwarf galaxy with a relatively high magnetic field can be a good candidate for constraining annihilating dark matter in future analyses.
NASA Astrophysics Data System (ADS)
Peylin, P. P.; Bacour, C.; MacBean, N.; Maignan, F.; Bastrikov, V.; Chevallier, F.
2017-12-01
Predicting the fate of carbon stocks and their sensitivity to climate change and land use/management strongly relies on our ability to accurately model net and gross carbon fluxes. However, simulated carbon and water fluxes remain subject to large uncertainties, partly because of unknown or poorly calibrated parameters. Over the past ten years, the carbon cycle data assimilation system at the Laboratoire des Sciences du Climat et de l'Environnement has investigated the benefit of assimilating multiple carbon cycle data streams into the ORCHIDEE LSM, the land surface component of the Institut Pierre Simon Laplace Earth System Model. These datasets have included FLUXNET eddy covariance data (net CO2 flux and latent heat flux) to constrain hourly to seasonal time-scale carbon cycle processes, remote sensing of the vegetation activity (MODIS NDVI) to constrain the leaf phenology, biomass data to constrain "slow" (yearly to decadal) processes of carbon allocation, and atmospheric CO2 concentrations to provide overall large scale constraints on the land carbon sink. Furthermore, we have investigated technical issues related to multiple data stream assimilation and choice of optimization algorithm. This has provided a wide-ranging perspective on the challenges we face in constraining model parameters and thus better quantifying, and reducing, model uncertainty in projections of the future global carbon sink. We review our past studies in terms of the impact of the optimization on key characteristics of the carbon cycle, e.g. the partition of the northern latitudes vs tropical land carbon sink, and compare to the classic atmospheric flux inversion approach. Throughout, we discuss our work in context of the abovementioned challenges, and propose solutions for the community going forward, including the potential of new observations such as atmospheric COS concentrations and satellite-derived Solar Induced Fluorescence to constrain the gross carbon fluxes of the ORCHIDEE model.
Beukelman, David R; Hux, Karen; Dietz, Aimee; McKelvey, Miechelle; Weissling, Kristy
2015-01-01
Research about the effectiveness of communicative supports and advances in photographic technology has prompted changes in the way speech-language pathologists design and implement interventions for people with aphasia. The purpose of this paper is to describe the use of photographic images as a basis for developing communication supports for people with chronic aphasia secondary to sudden-onset events due to cerebrovascular accidents (strokes). Topics include the evolution of AAC-based supports as they relate to people with aphasia, the development and key features of visual scene displays (VSDs), and future directions concerning the incorporation of photographs into communication supports for people with chronic and severe aphasia.
Velocity storage contribution to vestibular self-motion perception in healthy human subjects.
Bertolini, G; Ramat, S; Laurens, J; Bockisch, C J; Marti, S; Straumann, D; Palla, A
2011-01-01
Self-motion perception after a sudden stop from a sustained rotation in darkness lasts approximately as long as reflexive eye movements. We hypothesized that, after an angular velocity step, self-motion perception and reflexive eye movements are driven by the same vestibular pathways. In 16 healthy subjects (25-71 years of age), perceived rotational velocity (PRV) and the vestibulo-ocular reflex (rVOR) after sudden decelerations (90°/s(2)) from constant-velocity (90°/s) earth-vertical axis rotations were simultaneously measured (PRV reported by hand-lever turning; rVOR recorded by search coils). Subjects were upright (yaw) or 90° left-ear-down (pitch). After both yaw and pitch decelerations, PRV rose rapidly and showed a plateau before decaying. In contrast, slow-phase eye velocity (SPV) decayed immediately after the initial increase. SPV and PRV were fitted with the sum of two exponentials: one time constant accounting for the semicircular canal (SCC) dynamics and one time constant accounting for a central process, known as velocity storage mechanism (VSM). Parameters were constrained by requiring equal SCC time constant and VSM time constant for SPV and PRV. The gains weighting the two exponential functions were free to change. SPV were accurately fitted (variance-accounted-for: 0.85 ± 0.10) and PRV (variance-accounted-for: 0.86 ± 0.07), showing that SPV and PRV curve differences can be explained by a greater relative weight of VSM in PRV compared with SPV (twofold for yaw, threefold for pitch). These results support our hypothesis that self-motion perception after angular velocity steps is be driven by the same central vestibular processes as reflexive eye movements and that no additional mechanisms are required to explain the perceptual dynamics.
Sudden transition and sudden change from open spin environments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hu, Zheng-Da; School of Science, Jiangnan University, Wuxi 214122; Xu, Jing-Bo, E-mail: xujb@zju.edu.cn
2014-11-15
We investigate the necessary conditions for the existence of sudden transition or sudden change phenomenon for appropriate initial states under dephasing. As illustrative examples, we study the behaviors of quantum correlation dynamics of two noninteracting qubits in independent and common open spin environments, respectively. For the independent environments case, we find that the quantum correlation dynamics is closely related to the Loschmidt echo and the dynamics exhibits a sudden transition from classical to quantum correlation decay. It is also shown that the sudden change phenomenon may occur for the common environment case and stationary quantum discord is found at themore » high temperature region of the environment. Finally, we investigate the quantum criticality of the open spin environment by exploring the probability distribution of the Loschmidt echo and the scaling transformation behavior of quantum discord, respectively. - Highlights: • Sudden transition or sudden change from open spin baths are studied. • Quantum discord is related to the Loschmidt echo in independent open spin baths. • Steady quantum discord is found in a common open spin bath. • The probability distribution of the Loschmidt echo is analyzed. • The scaling transformation behavior of quantum discord is displayed.« less
Optimal vibration control of a rotating plate with self-sensing active constrained layer damping
NASA Astrophysics Data System (ADS)
Xie, Zhengchao; Wong, Pak Kin; Lo, Kin Heng
2012-04-01
This paper proposes a finite element model for optimally controlled constrained layer damped (CLD) rotating plate with self-sensing technique and frequency-dependent material property in both the time and frequency domain. Constrained layer damping with viscoelastic material can effectively reduce the vibration in rotating structures. However, most existing research models use complex modulus approach to model viscoelastic material, and an additional iterative approach which is only available in frequency domain has to be used to include the material's frequency dependency. It is meaningful to model the viscoelastic damping layer in rotating part by using the anelastic displacement fields (ADF) in order to include the frequency dependency in both the time and frequency domain. Also, unlike previous ones, this finite element model treats all three layers as having the both shear and extension strains, so all types of damping are taken into account. Thus, in this work, a single layer finite element is adopted to model a three-layer active constrained layer damped rotating plate in which the constraining layer is made of piezoelectric material to work as both the self-sensing sensor and actuator under an linear quadratic regulation (LQR) controller. After being compared with verified data, this newly proposed finite element model is validated and could be used for future research.
Astrophysical Model Selection in Gravitational Wave Astronomy
NASA Technical Reports Server (NTRS)
Adams, Matthew R.; Cornish, Neil J.; Littenberg, Tyson B.
2012-01-01
Theoretical studies in gravitational wave astronomy have mostly focused on the information that can be extracted from individual detections, such as the mass of a binary system and its location in space. Here we consider how the information from multiple detections can be used to constrain astrophysical population models. This seemingly simple problem is made challenging by the high dimensionality and high degree of correlation in the parameter spaces that describe the signals, and by the complexity of the astrophysical models, which can also depend on a large number of parameters, some of which might not be directly constrained by the observations. We present a method for constraining population models using a hierarchical Bayesian modeling approach which simultaneously infers the source parameters and population model and provides the joint probability distributions for both. We illustrate this approach by considering the constraints that can be placed on population models for galactic white dwarf binaries using a future space-based gravitational wave detector. We find that a mission that is able to resolve approximately 5000 of the shortest period binaries will be able to constrain the population model parameters, including the chirp mass distribution and a characteristic galaxy disk radius to within a few percent. This compares favorably to existing bounds, where electromagnetic observations of stars in the galaxy constrain disk radii to within 20%.
Sudden Infant Death Syndrome: Facts for Caregivers.
ERIC Educational Resources Information Center
Texas Child Care, 2000
2000-01-01
Presents risk factors and prevention measures related to Sudden Infant Death Syndrome. Offers infant sleep recommendations and five discussion questions to test knowledge of Sudden Infant Death Syndrome. (DLH)
Sudden cardiac death in adults: causes, incidence and interventions.
Walker, Wendy Marina
Many nurses will be familiar with the unexpected death of an adult patient following a sudden, life-threatening cardiac event. It is a situation that demands sensitive nursing care and skilled interventions to provide a foundation for recovery and promote healthy bereavement. This article examines the causes and incidence of sudden cardiac death in adults. Possible reactions of those who are suddenly bereaved are described and immediate care interventions aimed at dealing with the grief process are discussed. The article concludes by identifying ways in which the incidence of sudden cardiac death may be reduced.
Wireless sensor systems for sense/decide/act/communicate.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berry, Nina M.; Cushner, Adam; Baker, James A.
2003-12-01
After 9/11, the United States (U.S.) was suddenly pushed into challenging situations they could no longer ignore as simple spectators. The War on Terrorism (WoT) was suddenly ignited and no one knows when this war will end. While the government is exploring many existing and potential technologies, the area of wireless Sensor networks (WSN) has emerged as a foundation for establish future national security. Unlike other technologies, WSN could provide virtual presence capabilities needed for precision awareness and response in military, intelligence, and homeland security applications. The Advance Concept Group (ACG) vision of Sense/Decide/Act/Communicate (SDAC) sensor system is an instantiationmore » of the WSN concept that takes a 'systems of systems' view. Each sensing nodes will exhibit the ability to: Sense the environment around them, Decide as a collective what the situation of their environment is, Act in an intelligent and coordinated manner in response to this situational determination, and Communicate their actions amongst each other and to a human command. This LDRD report provides a review of the research and development done to bring the SDAC vision closer to reality.« less
Declining Risk of Sudden Death in Heart Failure.
Shen, Li; Jhund, Pardeep S; Petrie, Mark C; Claggett, Brian L; Barlera, Simona; Cleland, John G F; Dargie, Henry J; Granger, Christopher B; Kjekshus, John; Køber, Lars; Latini, Roberto; Maggioni, Aldo P; Packer, Milton; Pitt, Bertram; Solomon, Scott D; Swedberg, Karl; Tavazzi, Luigi; Wikstrand, John; Zannad, Faiez; Zile, Michael R; McMurray, John J V
2017-07-06
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 mineralocorticoid-receptor antagonists. We sought to examine this trend in detail. We analyzed data from 40,195 patients who had heart failure with reduced ejection fraction and were enrolled in any of 12 clinical trials spanning the period from 1995 through 2014. Patients who had an implantable cardioverter-defibrillator at the time of trial enrollment were excluded. Weighted multivariable regression was used to examine trends in rates of sudden death over time. Adjusted hazard ratios for sudden death in each trial group were calculated with the use of Cox regression models. The cumulative incidence rates of sudden death were assessed at different time points after randomization and according to the length of time between the diagnosis of heart failure and randomization. Sudden death was reported in 3583 patients. Such patients were older and were more often male, with an ischemic cause of heart failure and worse cardiac function, than those in whom sudden death did not occur. There was a 44% decline in the rate of sudden death across the trials (P=0.03). The cumulative incidence of sudden death at 90 days after randomization was 2.4% in the earliest trial and 1.0% in the most recent trial. The rate of sudden death was not higher among patients with a recent diagnosis of heart failure than among those with a longer-standing diagnosis. Rates of sudden death declined substantially over time among ambulatory patients with heart failure with reduced ejection fraction who were enrolled in clinical trials, a finding that is consistent with a cumulative benefit of evidence-based medications on this cause of death. (Funded by the China Scholarship Council and the University of Glasgow.).
Back muscle response to sudden trunk loading can be modified by training among healthcare workers.
Pedersen, Mogens Theisen; Essendrop, Morten; Skotte, Jørgen H; Jørgensen, Kurt; Schibye, Bente; Fallentin, Nils
2007-06-01
Experimental study of the effect of physical training on the reaction to sudden back loading. To investigate the effect and sustainability of "on the job training" on the reaction to sudden back loading among employees at a geriatric ward. 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. 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 intervention and at a 1-year follow-up, all subjects were tested for their reaction to expected and unexpected sudden trunk loading by applying a horizontal force of 58 N to the upper back of the subjects and measuring the electromyographic (EMG) response from the erector spinae muscles. In the training group, the stopping time and the distance moved after unexpected sudden trunk loading decreased significantly (13%-19%, P = 0.02). The improved stopping time was associated with marked changes in the time-wise distribution of the EMG signal after training. In addition, the follow-up study showed a high sustainability of the training effect. 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.
NASA Astrophysics Data System (ADS)
Quan, Lulin; Yang, Zhixin
2010-05-01
To address the issues in the area of design customization, this paper expressed the specification and application of the constrained surface deformation, and reported the experimental performance comparison of three prevail effective similarity assessment algorithms on constrained surface deformation domain. Constrained surface deformation becomes a promising method that supports for various downstream applications of customized design. Similarity assessment is regarded as the key technology for inspecting the success of new design via measuring the difference level between the deformed new design and the initial sample model, and indicating whether the difference level is within the limitation. According to our theoretical analysis and pre-experiments, three similarity assessment algorithms are suitable for this domain, including shape histogram based method, skeleton based method, and U system moment based method. We analyze their basic functions and implementation methodologies in detail, and do a series of experiments on various situations to test their accuracy and efficiency using precision-recall diagram. Shoe model is chosen as an industrial example for the experiments. It shows that shape histogram based method gained an optimal performance in comparison. Based on the result, we proposed a novel approach that integrating surface constrains and shape histogram description with adaptive weighting method, which emphasize the role of constrains during the assessment. The limited initial experimental result demonstrated that our algorithm outperforms other three algorithms. A clear direction for future development is also drawn at the end of the paper.
Advanced Electrocardiographic Predictors of Sudden Death in Familial Dysautonomia
NASA Technical Reports Server (NTRS)
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.
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 <0.001). After adjustment for participant demographics and clinical factors other than components of the metabolic syndrome, the metabolic syndrome was independently associated with sudden cardiac death (hazard ratio, 1.70, 95% confidence interval, 1.37-2.12, P <0.001). This relationship was not modified by sex (interaction P =0.10) or race (interaction P =0.62) and was mediated by the 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 <0.001). Of the 5 components, elevated blood pressure, impaired fasting glucose, and low high-density lipoprotein were independently associated with sudden cardiac death. We observed that the 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.
NASA Astrophysics Data System (ADS)
Rubin, Adam; PTF
2018-01-01
I will discuss our results studying light curves of hydrogen-rich supernovae during the first few days after explosion. The first days of emission encode important information about the physical system, and it is possible to relate the early-time light curve to the radius of the progenitor star by using shock-cooling models. I will show the first systematic application of these models to data from the Palomar Transient Factory (PTF). We found that R-band data alone at PTF cadence cannot constrain the radius but can constrain the energy per unit mass of the explosion, uncovering new correlations with other supernova observables. We constrained the radii for events with multi-wavelength observations, and for two events observed with the Kepler mission at 30 min cadence. I will discuss improved observing strategies to obtain more constraining results in the future. Some tensions have arisen between our results and the expected radii from identified progenitors of hydrogen-rich supernovae. The resolution of these tensions may be related to the effect of circumstellar material on the light curves, motivating future systematic spectroscopic sequencing of these events. To this end, we have designed a new medium resolution UV-VIS spectrograph. The Multi-Imaging Transient Spectrograph (MITS) is the R~4500 UV-VIS arm of the Son Of X-Shooter (SOXS) spectrograph proposed for ESO’s 3.6 m New Technology Telescope. Our design divides the spectrum into several sub-bands, allowing optimization for each narrow part of the spectrum. We estimate a 50-100% improvement in throughput relative to a classical 4-C echelle design. Our design has passed a preliminary design review and is expected on the telescope in early 2021.
[EPIDEMIOLOGY OF SUDDEN CARDIAC DEATH: DATA FROM THE PARIS SUDDEN DEATH EXPERTISE CENTER REGISTRY].
Jouven, Xavier; Bougouin, Wulfran; Karam, Nicole; Marijon, Eloi
2015-09-01
Sudden cardiac death is an unexpected cardiac arrest without obvious extra-cardiac cause. Epidemiology of sudden cardiac death has been poorly documented in France, mainly because of challenging requirement in order to capture all cases in a specific area. The Parisian registry (Sudden Death Expertise Center, European Georges Pompidou Hospital, Paris) was initiated in May 2011 and analyzed data of all sudden death in Paris and suburbs (6.6 millions inhabitants). Over 3 years, the annual incidence estimated to 50-70 per 100,000. Those occurred mainly in men (69%), with a mean age of 65 year, and at home (75%). The event was witnessed in 80% of cases, but bystander cardiopulmonary resuscitation was initiated in only half of cases. Initial cardiac rhythm was ventricular fibrillation in 25%. Survival to hospital discharge remains low (8%).
Benito Bartolomé, F; Sánchez Fernández-Bernal, C
2001-04-01
Sudden death may be the first manifestation of the Wolff-Parkinson-White syndrome, especially in children and adolescents. The aim of this study was to evaluate the usefulness of radiofrequency catheter ablation in children with Wolff-Parkinson-White syndrome with aborted sudden death. We report four patients with Wolff-Parkinson-White syndrome who survived cardiac arrest. The patients were aged from 2.5 months to 16 years. The two first patients were lactating infants; in the first sudden death occurred during digoxin treatment for supraventricular tachycardia secondary to Wolff-Parkinson-White syndrome and in the second the syndrome was diagnosed after an episode of sudden death. In these patients a free wall accessory pathway (left posterior and left lateral, respectively) was successfully ablated using a transseptal approach. The third patient was diagnosed with asymptomatic Wolff-Parkinson-White syndrome; sudden death occurred during exercise. In the fourth patient, sudden death occurred after intravenous therapy with adenosine triphosphate and amiodarone for rapid atrial fibrillation. In both patients, one accessory pathway, located in right posteroseptal and right anterior free wall, respectively, was ablated. After a mean follow-up of 43.5 26.4 months, no recurrence of sudden death had occurred and electrocardiogram showed sinus rhythm without delta wave. The third patient presented severe sequelae of hypoxemic encephalopathy, which persisted during the follow-up. Radiofrequency catheter ablation is the treatment of choice in Wolff-Parkinson-White syndrome with episodes of aborted sudden death.
Future cosmological sensitivity for hot dark matter axions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Archidiacono, Maria; Basse, Tobias; Hannestad, Steen
2015-05-01
We study the potential of a future, large-volume photometric survey to constrain the axion mass m{sub a} in the hot dark matter limit. Future surveys such as EUCLID will have significantly more constraining power than current observations for hot dark matter. Nonetheless, the lowest accessible axion masses are limited by the fact that axions lighter than ∼ 0.15 eV decouple before the QCD epoch, assumed here to occur at a temperature T{sub QCD} ∼ 170 MeV; this leaves an axion population of such low density that its late-time cosmological impact is negligible. For larger axion masses, m{sub a} ∼> 0.15 eV, where axions remain inmore » equilibrium until after the QCD phase transition, we find that a EUCLID-like survey combined with Planck CMB data can detect m{sub a} at very high significance. Our conclusions are robust against assumptions about prior knowledge of the neutrino mass. Given that the proposed IAXO solar axion search is sensitive to m{sub a}∼<0.2 eV, the axion mass range probed by cosmology is nicely complementary.« less
To the horizon and beyond: Weak lensing of the CMB and binary inspirals into horizonless objects
NASA Astrophysics Data System (ADS)
Kesden, Michael
This thesis examines two predictions of general relativity: weak lensing and gravitational waves. The cosmic microwave background (CMB) is gravitationally lensed by the large-scale structure between the observer and the last- scattering surface. This weak lensing induces non-Gaussian correlations that can be used to construct estimators for the deflection field. The error and bias of these estimators are derived and used to analyze the viability of lensing reconstruction for future CMB experiments. Weak lensing also affects the one-point probability distribution function of the CMB. The skewness and kurtosis induced by lensing and the Sunayev- Zel'dovich (SZ) effect are calculated as functions of the angular smoothing scale of the map. While these functions offer the advantage of easy computability, only the skewness from lensing-SZ correlations can potentially be detected, even in the limit of the largest amplitude fluctuations allowed by observation. Lensing estimators are also essential to constrain inflation, the favored explanation for large-scale isotropy and the origin of primordial perturbations. B-mode polarization is considered to be a "smoking-gun" signature of inflation, and lensing estimators can be used to recover primordial B-modes from lensing-induced contamination. The ability of future CMB experiments to constrain inflation is assessed as functions of survey size and instrumental sensitivity. A final application of lensing estimators is to constrain a possible cutoff in primordial density perturbations on near-horizon scales. The paucity of independent modes on such scales limits the statistical certainty of such a constraint. Measurements of the deflection field can be used to constrain at the 3s level the existence of a cutoff large enough to account for current CMB observations. A final chapter of this thesis considers an independent topic: the gravitational-wave (GW) signature of a binary inspiral into a horizonless object. If the supermassive objects at galactic centers lack the horizons of traditional black holes, inspiraling objects could emit GWs after passing within their surfaces. The GWs produced by such an inspiral are calculated, revealing distinctive features potentially observable by future GW observatories.
Probing Models of Dark Matter and the Early Universe
NASA Astrophysics Data System (ADS)
Orlofsky, Nicholas David
This thesis discusses models for dark matter (DM) and their behavior in the early universe. An important question is how phenomenological probes can directly search for signals of DM today. Another topic of investigation is how the DM and other processes in the early universe must evolve. Then, astrophysical bounds on early universe dynamics can constrain DM. We will consider these questions in the context of three classes of DM models--weakly interacting massive particles (WIMPs), axions, and primordial black holes (PBHs). Starting with WIMPs, we consider models where the DM is charged under the electroweak gauge group of the Standard Model. Such WIMPs, if generated by a thermal cosmological history, are constrained by direct detection experiments. To avoid present or near-future bounds, the WIMP model or cosmological history must be altered in some way. This may be accomplished by the inclusion of new states that coannihilate with the WIMP or a period of non-thermal evolution in the early universe. Future experiments are likely to probe some of these altered scenarios, and a non-observation would require a high degree of tuning in some of the model parameters in these scenarios. Next, axions, as light pseudo-Nambu-Goldstone bosons, are susceptible to quantum fluctuations in the early universe that lead to isocurvature perturbations, which are constrained by observations of the cosmic microwave background (CMB). We ask what it would take to allow axion models in the face of these strong CMB bounds. We revisit models where inflationary dynamics modify the axion potential and discuss how isocurvature bounds can be relaxed, elucidating the difficulties in these constructions. Avoiding disruption of inflationary dynamics provides important limits on the parameter space. Finally, PBHs have received interest in part due to observations by LIGO of merging black hole binaries. We ask how these PBHs could arise through inflationary models and investigate the opportunity for corroboration through experimental probes of gravitational waves at pulsar timing arrays. We provide examples of theories that are already ruled out, theories that will soon be probed, and theories that will not be tested in the foreseeable future. The models that are most strongly constrained are those with relatively broad primordial power spectra.
Phillips, Susie B; Batlivala, Sarosh; Knudson, Jarrod D
2015-10-01
Common aetiologies of sudden cardiac death in children include coronary anomalies, channelopathies, and cardiomyopathies. Less frequently, hypercoagulable states cause sudden arrest. We report an unusual case of aborted sudden cardiac death in a teenager, ultimately found to have homozygosity for the 4G allele of the plasminogen activase inhibitor type 1 gene.
Sudden death: bereavement sequelae and interventions.
Davidson, G P
1981-10-14
Just the phrase "sudden death' carries its sense of trepidation and even horror. So fear-inducing is its reality and prospect, that we have attempted to sanitise it by the colloquialisms such as a "sudden death play off' in sport, and even (recalling my days in military service) as the name of a particularly ferocious mix of alcoholic beverage. One of the reasons why the phrase is so evocative is the force of the unexpected bereavement that follows sudden death. This paper purports to examine, using a systems approach, the psychological sequelae of the emotionally involved survivors of sudden death, and to relate this to possible intervention strategies.
Sudden Cardiac Arrest (SCA) Risk Assessment
... HRS Find a Specialist Share Twitter Facebook SCA Risk Assessment Sudden Cardiac Arrest (SCA) occurs abruptly and without ... people of all ages and health conditions. Start Risk Assessment The Sudden Cardiac Arrest (SCA) Risk Assessment Tool ...
Using palaeoclimate data to improve models of the Antarctic Ice Sheet
NASA Astrophysics Data System (ADS)
Phipps, Steven; King, Matt; Roberts, Jason; White, Duanne
2017-04-01
Ice sheet models are the most descriptive tools available to simulate the future evolution of the Antarctic Ice Sheet (AIS), including its contribution towards changes in global sea level. However, our knowledge of the dynamics of the coupled ice-ocean-lithosphere system is inevitably limited, in part due to a lack of observations. Furthemore, to build computationally efficient models that can be run for multiple millennia, it is necessary to use simplified descriptions of ice dynamics. Ice sheet modelling is therefore an inherently uncertain exercise. The past evolution of the AIS provides an opportunity to constrain the description of physical processes within ice sheet models and, therefore, to constrain our understanding of the role of the AIS in driving changes in global sea level. We use the Parallel Ice Sheet Model (PISM) to demonstrate how palaeoclimate data can improve our ability to predict the future evolution of the AIS. A 50-member perturbed-physics ensemble is generated, spanning uncertainty in the parameterisations of three key physical processes within the model: (i) the stress balance within the ice sheet, (ii) basal sliding and (iii) calving of ice shelves. A Latin hypercube approach is used to optimally sample the range of uncertainty in parameter values. This perturbed-physics ensemble is used to simulate the evolution of the AIS from the Last Glacial Maximum ( 21,000 years ago) to present. Palaeoclimate records are then used to determine which ensemble members are the most realistic. This allows us to use data on past climates to directly constrain our understanding of the past contribution of the AIS towards changes in global sea level. Critically, it also allows us to determine which ensemble members are likely to generate the most realistic projections of the future evolution of the AIS.
Using paleoclimate data to improve models of the Antarctic Ice Sheet
NASA Astrophysics Data System (ADS)
King, M. A.; Phipps, S. J.; Roberts, J. L.; White, D.
2016-12-01
Ice sheet models are the most descriptive tools available to simulate the future evolution of the Antarctic Ice Sheet (AIS), including its contribution towards changes in global sea level. However, our knowledge of the dynamics of the coupled ice-ocean-lithosphere system is inevitably limited, in part due to a lack of observations. Furthemore, to build computationally efficient models that can be run for multiple millennia, it is necessary to use simplified descriptions of ice dynamics. Ice sheet modeling is therefore an inherently uncertain exercise. The past evolution of the AIS provides an opportunity to constrain the description of physical processes within ice sheet models and, therefore, to constrain our understanding of the role of the AIS in driving changes in global sea level. We use the Parallel Ice Sheet Model (PISM) to demonstrate how paleoclimate data can improve our ability to predict the future evolution of the AIS. A large, perturbed-physics ensemble is generated, spanning uncertainty in the parameterizations of four key physical processes within ice sheet models: ice rheology, ice shelf calving, and the stress balances within ice sheets and ice shelves. A Latin hypercube approach is used to optimally sample the range of uncertainty in parameter values. This perturbed-physics ensemble is used to simulate the evolution of the AIS from the Last Glacial Maximum ( 21,000 years ago) to present. Paleoclimate records are then used to determine which ensemble members are the most realistic. This allows us to use data on past climates to directly constrain our understanding of the past contribution of the AIS towards changes in global sea level. Critically, it also allows us to determine which ensemble members are likely to generate the most realistic projections of the future evolution of the AIS.
Testing inflation and curvaton scenarios with CMB distortions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clesse, Sébastien; Garbrecht, Björn; Zhu, Yi, E-mail: s.clesse@tum.de, E-mail: garbrecht@tum.de, E-mail: yi.zhu@tum.de
2014-10-01
Prior to recombination, Silk damping causes the dissipation of energy from acoustic waves into the monopole of the Cosmic Microwave Background (CMB), resulting in spectral distortions. These can be used to probe the primordial scalar power spectrum on smaller scales than it is possible with CMB anisotropies. An enhancement of power on these scales is nevertheless required for the resulting distortions to be detectable by future experiments like PIXIE. In this paper, we examine all 49 single-field inflation models listed by Martin et al. in the Encyclopaedia Inflationaris [1] and find that only one of these may lead to amore » detectable level of distortions in a tuned region of its parameter space, namely the original hybrid model. Three effective multi-field scenarios are also studied: with softly and suddenly turning trajectories, and with a mild waterfall trajectory. Softly turning trajectories do not induce distortions at any detectable level, whereas a sudden turn in the field space or a mild waterfall trajectory predicts a peak (plus damped oscillations in the sudden turn case) in the scalar power spectrum, which can lead to an observable amount of CMB distortions. Finally, another scenario leading to potentially detectable distortions involves a curvaton whose blue spectrum is subdominant on CMB angular scales and overtakes the inflaton spectrum on smaller scales. In this case however, we show that the bounds from ultra compact minihaloes are not satisfied. Expectations for an ultimate PRISM-class experiment characterized by an improvement in sensitivity by a factor of ten are discussed for some models.« less
An experimental cadaveric study for a better understanding of blunt traumatic aortic rupture.
Baqué, Patrick; Serre, Thierry; Cheynel, Nicolas; Arnoux, Pierre-Jean; Thollon, Lionel; Behr, Michel; Masson, Catherine; Delotte, Jérôme; Berdah, Stéphane-Victor; Brunet, Christian
2006-09-01
Blunt traumatic aortic rupture (BTAR) is a common catastrophic injury leading to death. Considerable uncertainty remains regarding the pathogenic cause. This study examines the comportment of the heart and the aorta during a frontal deceleration. Accelerometers were placed in the right ventricle of the heart, the aorta, the sternum, and the spine of six trunks removed from human cadavers. Different vertical decelerations were applied to cadavers and the relative motion of these organs was studied (19 tests). The deceleration recorded in the isthmus of the aorta was always higher that the one recorded in the heart (p < 0.05). The difference of deceleration was 17% and increased with the speed's fall (extremes 5-25%). There was no significant difference of deceleration between the bony structures of the thorax. These results experimentally demonstrate for the first time that the fundamental mechanism of BTAR is sudden stretching of the isthmus of the aorta. Four mechanisms are suspected to explain the location of the rupture: two hemodynamic mechanism (sudden increase of intravascular pressure and the water-hammer effect), and two physical mechanisms (sudden stretching of the isthmus and the osseous pinch). A greater understanding of the mechanism of this injury could improve vehicle safety leading to a reduction in its incidence and severity. Future work in this area should include the creation of an inclusive, dynamic model of computer-based modeling systems. This study provides for the first time physical demonstration and quantification of the stretching of the isthmus, leading to a computerized model of BTAR.
Weber, M A; Ashworth, M T; Risdon, R A; Hartley, J C; Malone, M; Sebire, N J
2008-12-01
Several autopsy protocols have been suggested for investigating sudden unexpected deaths in infancy (SUDI). The aim of this study is to provide data on the utility of such post-mortem investigations from a large paediatric autopsy series to inform future policy. Retrospective analysis of >1500 consecutive post-mortem examinations carried out by specialist paediatric pathologists at a single centre during a 10-year period according to a common autopsy protocol that included the use of detailed ancillary investigations. SUDI was defined as the sudden unexpected death of an infant aged from 7 to 365 days. All data capture and cause of death classification were carried out according to defined criteria. Of 1516 paediatric post-mortem examinations, 546 presented as SUDI. In 202 infants (37%), death was explained by the autopsy findings. The other 344 cases (63%) remained unexplained. Of the explained deaths, over half (58%) were infective, most commonly due to pneumonia (22%). The component of the post-mortem examination that primarily determined the final cause of death was histological examination in 92 infants (46%), macroscopic examination in 61 (30%), microbiological investigations in 38 (19%) and clinical history in 10 (5%). This constitutes the largest single-institution autopsy study of SUDI. Ten years on from the Confidential Enquiry into Stillbirths and Deaths in Infancy (CESDI) SUDI studies, the ascertainment of a cause of death at autopsy has improved. However, with almost two thirds of SUDI remaining unexplained, alternative and/or additional diagnostic techniques are required to improve detection rates of identifiable causes of death at autopsy.
KAMEDO report No. 93-the power failure at Karolinska University Hospital, Huddinge, 07 April 2007.
Angantyr, Lars-Göran; Häggström, Eskil; Kulling, Per
2009-01-01
A sudden and extensive power failure occurred at Karolinska University Hospital in Huddinge on Easter Saturday, 07 April 2007. The power failure lasted one hour and 22 minutes, but it took a longer time for activities to return to normal. It put many patients at great risk, particularly in the intensive care unit and other departments with critically ill patients. This report details the conditions and response at Karolinska University Hospital during the power failure and provides lessons learned for future events.
Geothermal energy employment and requirements 1977-1990
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-12-01
An assessment of the manpower needs of the geothermal industry is presented. The specific objectives were to: derive a base line estimate of the manpower involved in geothermal activities, determine if there is any current or impending likelihood of skill shortages, forecast future employment in the geothermal industry, conduct a technology assessment to ascertain the possibilities of some sudden breakthrough, and suggest alternatives commensurate with the findings. The methodology for fulfilling the objectives is described. Detailed results of these pursuits (objectives) are presented. Alternatives that are suggested, based upon the findings of the study, are summarized.
Environmental and medical geochemistry in urban disaster response and preparedness
Plumlee, Geoffrey S.; Morman, Suzette A.; Cook, A.
2012-01-01
History abounds with accounts of cities that were destroyed or significantly damaged by natural or anthropogenic disasters, such as volcanic eruptions, earthquakes, wildland–urban wildfires, hurricanes, tsunamis, floods, urban firestorms, terrorist attacks, and armed conflicts. Burgeoning megacities place ever more people in the way of harm from future disasters. In addition to the physical damage, casualties, and injuries they cause, sudden urban disasters can also release into the environment large volumes of potentially hazardous materials. Environmental and medical geochemistry investigations help us to (1) understand the sources and environmental behavior of disaster materials, (2) assess potential threats the materials pose to the urban environment and health of urban populations, (3) develop strategies for their cleanup/disposal, and (4) anticipate and mitigate potential environmental and health effects from future urban disasters.
Mobile phone usage does not affect sudden sensorineural hearing loss.
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.
NASA Astrophysics Data System (ADS)
Doubre, C.; Socquet, A.; Masson, F.; Jacques, E.; Grandin, R.; Nercessian, A.; Kassim, M.; Vergne, J.; Diament, M.; Hinderer, J.; Ayele, A.; Lewi, E.; Calais, E.; Peltzer, G.; Toussaint, R.; de Chaballier, J.; Ballu, V. S.; Luck, B.; King, G. C.; Vigny, C.; Cattin, R.; Tiberi, C.; Kidane, T.; Jalludin, M.; Maggi, A.; Dorbath, C.; Manatschal, G.; Schmittbuhl, J.; Le Moigne, N.; Deroussi, S.
2009-12-01
The DoRA project aims to conduct complementary studies in two volcano-tectonic rifts in the Afar Depression. In Northern Afar, the Wal’is Dabbahu Rift (WD, Ethiopia) is currently undergoing a major rifting episode. This event started in September 2005 with a significant seismic activity. InSAR data revealed the injection of a 65 km-long mega-dyke that opened by up to 8 m, the slip of numerous normal faults and opening of fissures, and a rhyolitic eruption. Similarly, the Asal-Ghoubbet Rift (AG, Djibouti) was affected in 1978 by a smaller episode of rifting associated with the intrusion of a 2 m wide dyke into the crust. Since then, a large catalog of geodetic data that includes recent InSAR time series reveals the importance of non-steady deformation controlling the rift dynamics. Our goal is to gain an understanding of such volcano-tectonic segments on several time scales, including the dyking period itself and the post-event period. The study of the behavior of the AG Rift during its whole post-rifting period offers an image at t+30 years of the WD segment, while keeping in mind important structural and scale differences. First, we propose to build a complete and accurate set of geodetic data (InSAR, cGPS, GPS), covering the period under study. With a narrow temporal sample window, we will precisely describe the aseismic slip affecting the normal faults of these rifts, the periods of sudden slip and/or slip acceleration but also measure the deformation associated with probable future dyke intrusion. Second, we aim to constrain the origin of these displacements and their relation with mass transfers within the crust. Series of gravity measurements will be pursue or initiated in both rifts. Third, the recording of seismic activity is essential to constrain the relative importance of seismic and aseismic deformation. This will also help to evaluate the thickness of the seismogenic layer. Together with structural data collected during a seismic survey in the AG Rift, these results will offer crucial constraints on modeling the rifting dynamics in order to test the relative influences of the rheology, the fault/dyke geometry and fluids on the rupture mechanics, the viscous relaxation, dyke intrusion/inflation and aseismic slip and their interactions. Our multidisciplinary approach should provide important new constraints on the dynamics of rifting along divergent plate boundaries, and ultimately, in other geodynamical contexts affected by aseismic fault slip transients.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gerbino, Martina; Gruppuso, Alessandro; Natoli, Paolo
We use the 2015 Planck likelihood in combination with the Bicep2/Keck likelihood (BKP and BK14) to constrain the chirality, χ, of primordial gravitational waves in a scale-invariant scenario. In this framework, the parameter χ enters theory always coupled to the tensor-to-scalar ratio, r , e.g. in combination of the form χ ⋅ r . Thus, the capability to detect χ critically depends on the value of r . We find that with present data sets χ is de facto unconstrained. We also provide forecasts for χ from future CMB experiments, including COrE+, exploring several fiducial values of r . Wemore » find that the current limit on r is tight enough to disfavor a neat detection of χ. For example, in the unlikely case in which r ∼0.1(0.05), the maximal chirality case, i.e. χ = ±1, could be detected with a significance of ∼2.5(1.5)σ at best. We conclude that the two-point statistics at the basis of CMB likelihood functions is currently unable to constrain chirality and may only provide weak limits on χ in the most optimistic scenarios. Hence, it is crucial to investigate the use of other observables, e.g. provided by higher order statistics, to constrain these kinds of parity violating theories with the CMB.« less
PROJECTING WILDLIFE RESPONSES TO ALTERNATIVE FUTURE LANDSCAPES IN OREGON'S WILLAMETTE VALLEY
Increasingly, environmental quality is becoming recognized as a critical factor that should constrain land use planning. One important measure of a landscape's quality is its capacity to support viable populations of wildlife species. But the ability of land managers to balance c...
NASA Astrophysics Data System (ADS)
Alves, C. S.; Leite, A. C. O.; Martins, C. J. A. P.; Silva, T. A.; Berge, S. A.; Silva, B. S. A.
2018-01-01
There is a growing interest in astrophysical tests of the stability of dimensionless fundamental couplings, such as the fine-structure constant α , as an optimal probe of new physics. The imminent arrival of the ESPRESSO spectrograph will soon enable significant gains in the precision and accuracy of these tests and widen the range of theoretical models that can be tightly constrained. Here we illustrate this by studying proposed extensions of the Bekenstein-type models for the evolution of α that allow different couplings of the scalar field to both dark matter and dark energy. We use a combination of current astrophysical and local laboratory data (from tests with atomic clocks) to show that these couplings are constrained to parts per million level, with the constraints being dominated by the atomic clocks. We also quantify the expected improvements from ESPRESSO and other future spectrographs, and briefly discuss possible observational strategies, showing that these facilities can improve current constraints by more than an order of magnitude.
On exploration of geometrically constrained space by medicinal leeches Hirudo verbana.
Adamatzky, Andrew
2015-04-01
Leeches are fascinating creatures: they have simple modular nervous circuitry yet exhibit a rich spectrum of behavioural modes. Leeches could be ideal blue-prints for designing flexible soft robots which are modular, multi-functional, fault-tolerant, easy to control, capable for navigating using optical, mechanical and chemical sensorial inputs, have autonomous inter-segmental coordination and adaptive decision-making. With future designs of leech-robots in mind we study how leeches behave in geometrically constrained spaces. Core results of the paper deal with leeches exploring a row of rooms arranged along a narrow corridor. In laboratory experiments we find that rooms closer to ends of the corridor are explored by leeches more often than rooms in the middle of the corridor. Also, in series of scoping experiments, we evaluate leeches capabilities to navigating in mazes towards sources of vibration and chemo-attraction. We believe our results lay foundation for future developments of robots mimicking behaviour of leeches. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Shi, J R; Tian, C J; Zeng, Q; Guo, X J; Lu, J; Gao, C R
2016-06-01
To explore the value of mast cell tryptase and brain natriuretic peptide(BNP) in the differential diagnostic of sudden death due to hypersensitivity and coronary atherosclerotic heart disease. Totally 30 myocardial samples were collected from the autopsy cases in the Department of Forensic Pathology, Shanxi Medical University during 2010-2015. All samples were divided into three groups: death of craniocerebral injury group, sudden death of hypersensitivity group and sudden death of coronary atherosclerotic heart disease group, 10 cases in each group. Mast cell tryptase and BNP in myocardium were detected by immunofluorescence staining and Western Blotting. Immunofluorescence staining showed that the positive staining mast cell tryptase appeared in myocardium of sudden death of hypersensitivity group and coronary atherosclerotic heart disease group. Among the three groups, the expression of mast cell tryptase showed significantly differences through pairwise comparison ( P <0.05); The expression level of BNP in sudden death of coronary atherosclerotic heart disease group were significantly higher than the sudden death of hypersensitivity group and death of craniocerebral injury group ( P <0.05). The difference of the expression level of BNP between the sudden death of hypersensitivity group and the death of craniocerebral injury group had no statistical significance ( P >0.05). The combined detection of the mast cell tryptase and BNP in myocardium is expected to provide help for the forensic differential diagnosis of sudden death due to hypersensitivity and coronary atherosclerotic heart disease. Copyright© by the Editorial Department of Journal of Forensic Medicine
Genetics Home Reference: sudden infant death with dysgenesis of the testes syndrome
... Facebook Twitter Home Health Conditions SIDDT Sudden infant death with dysgenesis of the testes syndrome Printable PDF ... view the expand/collapse boxes. Description Sudden infant death with dysgenesis of the testes syndrome ( SIDDT ) is ...
van der Wel, Robrecht P; Welsh, Timothy; Böckler, Anne
2018-01-01
The direction of gaze towards or away from an observer has immediate effects on attentional processing in the observer. Previous research indicates that faces with direct gaze are processed more efficiently than faces with averted gaze. We recently reported additional processing advantages for faces that suddenly adopt direct gaze (abruptly shift from averted to direct gaze) relative to static direct gaze (always in direct gaze), sudden averted gaze (abruptly shift from direct to averted gaze), and static averted gaze (always in averted gaze). Because changes in gaze orientation in previous study co-occurred with changes in head orientation, it was not clear if the effect is contingent on face or eye processing, or whether it requires both the eyes and the face to provide consistent information. The present study delineates the impact of head orientation, sudden onset motion cues, and gaze cues. Participants completed a target-detection task in which head position remained in a static averted or direct orientation while sudden onset motion and eye gaze cues were manipulated within each trial. The results indicate a sudden direct gaze advantage that resulted from the additive role of motion and gaze cues. Interestingly, the orientation of the face towards or away from the observer did not influence the sudden direct gaze effect, suggesting that eye gaze cues, not face orientation cues, are critical for the sudden direct gaze effect.
State of the art in forensic investigation of sudden cardiac death.
Oliva, Antonio; Brugada, Ramon; D'Aloja, Ernesto; Boschi, Ilaria; Partemi, Sara; Brugada, Josep; Pascali, Vincenzo L
2011-03-01
The sudden death of a young person is a devastating event for both the family and community. Over the last decade, significant advances have been made in understanding both the clinical and genetic basis of sudden cardiac death. Many of the causes of sudden death are due to genetic heart disorders, which can lead to both structural (eg, hypertrophic cardiomyopathy) and arrhythmogenic abnormalities (eg, familial long QT syndrome, Brugada syndrome). Most commonly, sudden cardiac death can be the first presentation of an underlying heart problem, leaving the family at a loss as to why an otherwise healthy young person has died. Not only is this a tragic event for those involved, but it also presents a great challenge to the forensic pathologist involved in the management of the surviving family members. Evaluation of families requires a multidisciplinary approach, which should include cardiologists, a clinical geneticist, a genetic counselor, and the forensic pathologist directly involved in the sudden death case. This multifaceted cardiac genetic service is crucial in the evaluation and management of the clinical, genetic, psychological, and social complexities observed in families in which there has been a young sudden cardiac death. The present study will address the spectrum of structural substrates of cardiac sudden death with particular emphasis given to the possible role of forensic molecular biology techniques in identifying subtle or even merely functional disorders accounting for electrical instability.
Gastrointestinal causes of sudden unexpected death: A review.
Menezes, Ritesh G; Ahmed, Saba; Pasha, Syed Bilal; Hussain, Syed Ather; Fatima, Huda; Kharoshah, Magdy A; Madadin, Mohammed
2018-01-01
Gastrointestinal conditions are a less common cause of sudden unexpected death when compared to other conditions such as cardiovascular conditions, but they are equally important. Various congenital and acquired gastrointestinal conditions that have resulted in sudden unexpected death are discussed. The possible lethal mechanisms behind each condition, along with any associated risk factors or secondary diseases, have been described. Through this article, we aim to highlight the need for physicians to prevent death in such conditions by ensuring that subclinical cases are diagnosed correctly before it is too late and by providing timely and efficacious treatment to the patient concerned. In addition, this review would certainly benefit the forensic pathologist while dealing with cases of sudden unexpected death due to gastrointestinal causes. This article is a review of the major gastrointestinal causes of sudden unexpected death. In addition, related fatal cases encountered occasionally in forensic autopsy practice are also included. There are several unusual and rare causes of life-threatening gastrointestinal bleeding that may lead to sudden unexpected death to cover all the entities in detail. Nevertheless, this article is a general guide to the topic of gastrointestinal causes of sudden unexpected death.
Sudden Cardiac Arrest in Athletic Medicine
Kyle, James M.; Ellis, James M.; Cantwell, John; Courson, Ron; Medlin, Ron
2001-01-01
Objective: To emphasize the importance of decreasing the response time by a trained target responder to increase the survival rate among athletes experiencing sudden cardiac arrest at an athletic event. Background: Death due to sudden cardiac arrest that is witnessed is preventable in many cases. However, most people who experience this condition die because of a prolonged response time from onset of the fatal arrhythmia to defibrillation by trained treatment providers. If athletic trainers or other members of the athletic care medical team are trained as target responders and equipped with automated electronic defibrillators, they can immediately treat an athlete who experiences a sudden, life-threatening tachyarrhythmia. This prompt response to the life-threatening emergency should result in a higher survival rate. Description: We review the causes of sudden cardiac arrest during athletic events, note some unusual clinical presentations, discuss improved methods of response and new equipment for treatment, and define the athletic trainer's role as a target responder trained to treat people experiencing sudden cardiac arrest at an athletic event. Clinical Advantages: An athletic care team willing to become part of an emergency response team can help improve the survival rate of athletes experiencing sudden cardiac arrest at an athletic event. PMID:12937464
F-MARC: promoting the prevention and management of sudden cardiac arrest in football
Kramer, Efraim Benjamin; Dvorak, J; Schmied, C; Meyer, T
2015-01-01
Sudden cardiac death is the most common cause of unnatural death in football. To prevent and urgently manage sudden cardiac arrest on the football field-of-play, F-MARC (FIFA Medical and Research Centre) has been fully committed to a programme of research, education, standardisation and practical implementation. This strategy has detected football players at medical risk during mandatory precompetition medical assessments. Additionally, FIFA has (1) sponsored internationally accepted guidelines for the interpretation of an athlete's ECG, (2) developed field-of-play-specific protocols for the recognition, response, resuscitation and removal of a football player having sudden cardiac arrest and (3) introduced and distributed the FIFA medical emergency bag which has already resulted in the successful resuscitation of a football player who had a sudden cardiac arrest on the field-of-play. Recently FIFA, in association with the Institute of Sports and Preventive Medicine in Saarbrücken, Germany, established a worldwide Sudden Death Registry with a view to documenting fatal events on the football field-of-play. These activities by F-MARC are testimony to FIFA's continued commitment to minimising sudden cardiac arrest while playing football. PMID:25878076
Characterizing biospheric carbon balance using CO2 observations from the OCO-2 satellite
NASA Astrophysics Data System (ADS)
Miller, Scot M.; Michalak, Anna M.; Yadav, Vineet; Tadić, Jovan M.
2018-05-01
NASA's Orbiting Carbon Observatory 2 (OCO-2) satellite launched in summer of 2014. Its observations could allow scientists to constrain CO2 fluxes across regions or continents that were previously difficult to monitor. This study explores an initial step toward that goal; we evaluate the extent to which current OCO-2 observations can detect patterns in biospheric CO2 fluxes and constrain monthly CO2 budgets. Our goal is to guide top-down, inverse modeling studies and identify areas for future improvement. We find that uncertainties and biases in the individual OCO-2 observations are comparable to the atmospheric signal from biospheric fluxes, particularly during Northern Hemisphere winter when biospheric fluxes are small. A series of top-down experiments indicate how these errors affect our ability to constrain monthly biospheric CO2 budgets. We are able to constrain budgets for between two and four global regions using OCO-2 observations, depending on the month, and we can constrain CO2 budgets at the regional level (i.e., smaller than seven global biomes) in only a handful of cases (16 % of all regions and months). The potential of the OCO-2 observations, however, is greater than these results might imply. A set of synthetic data experiments suggests that retrieval errors have a salient effect. Advances in retrieval algorithms and to a lesser extent atmospheric transport modeling will improve the results. In the interim, top-down studies that use current satellite observations are best-equipped to constrain the biospheric carbon balance across only continental or hemispheric regions.
Exploring links between greenspace and sudden unexpected death: a spatial analysis
Greenspace has been increasingly recognized as having numerous health benefits. However, its effects are unknown concerning sudden unexpected death (SUD), commonly referred to as sudden cardiac death, which constitutes a large proportion of mortality in the United States. Because...
Residual entanglement and sudden death: A direct connection
NASA Astrophysics Data System (ADS)
de Oliveira, J. G. G.; Peixoto de Faria, J. G.; Nemes, M. C.
2011-11-01
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.
Epidemiological characteristics of sudden cardiac arrest in schools.
Nishiuchi, Tatsuya; Hayashino, Yasuaki; Iwami, Taku; Kitamura, Tetsuhisa; Nishiyama, Chika; Kajino, Kentaro; Nitta, Masahiko; Hayashi, Yasuyuki; Hiraide, Atsushi
2014-08-01
The present study aimed to clarify the incidence and outcomes of sudden cardiac arrests in schools and the clinically relevant characteristics of individuals who experienced sudden cardiac arrests. We obtained data on sudden cardiac arrests that occurred in schools between January 1, 2005 and December 31, 2009 from the database of the Utstein Osaka Project, a population-based observational study on out-of-hospital cardiac arrests in Osaka, Japan. The data were analyzed to show the epidemiological features of sudden cardiac arrests in schools in conjunction with prehospital documentation. In total, 44 cases were registered as sudden cardiac arrests in schools during the study period. Of these, 34 cases had nontraumatic cardiac arrests. Twenty-one cases (62%) had pre-existing cardiac diseases and/or collapsed during physical exercise. Twenty-three cases (68%) presented with ventricular fibrillation or pulseless ventricular tachycardia, with cases of survival 1 month after cardiac arrest and those having favourable neurological outcome (Cerebral Performance Category 1 or 2) being 12 (52%) and 10 (43%), respectively. The incidence of sudden cardiac arrests in students was 0.23 per 100,000 persons per year, ranging from 0.08 in junior high school to 0.64 in high school. The incidence of sudden cardiac arrests in school faculty and staff was 0.51 per 100,000 persons per year, a rate approximately 2 times of that observed in the students. Although sudden cardiac arrests in schools is rare, they majorly occurred in individuals with cardiac diseases and/or during physical exercise and presented as ventricular fibrillation or pulseless ventricular tachycardia observed initially as cardiac arrhythmia. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Chugh, Sumeet S; Chung, Kiyon; Zheng, Zhi-Jie; John, Benjamin; Titus, Jack L
2003-10-01
Between 1989 and 1998 there was a 21% increase in estimated sudden cardiac death among US women aged 35 to 44 years. In contrast, the sudden cardiac death rate in age-matched men showed a decreasing trend (-2.8%). Due to under-representation of younger adults in published autopsy series, etiologies of sudden cardiac death merit further investigation. We reviewed autopsy and detailed cardiac pathologic findings in younger women (age 35-44 years) from a 270-patient, 13-year (1984-1996) autopsy series of sudden cardiac death, and performed comparisons with findings in age-matched men. Women aged 35 to 44 years constituted 32% of all women in the series compared to men, who constituted 24% of total men (P =.004 vs women). A presumptive cause of sudden cardiac death could not be determined in 13 women (50%). Among women, 6 cases (22%) had significant coronary artery disease. Findings in others included coronary artery anomalies (n = 3), myocarditis (n = 2), hypertrophic cardiomyopathy (n = 1), coronary artery dissection (n = 1) and accessory pathway (n = 1). In younger men, a presumptive cause of sudden cardiac death remained undetermined in only 24% (P =.025 vs younger women), and coronary artery disease accounted for 40% of cases. In younger women, despite autopsy and detailed cardiac pathologic examination, an attributable cause of sudden cardiac death was not determined in 50% of cases; a 2-fold increase compared to men of the same age. Given the dynamic and multifactorial nature of sudden cardiac death, comprehensive population-based investigations are likely to be necessary to further investigate this unexpected sex-based disparity.
Le, Hai-Ha; Subtil, Fabien; Cerou, Marc; Marchant, Ivanny; Al-Gobari, Muaamar; Fall, Mor; Mimouni, Yanis; Kassaï, Behrouz; Lindholm, Lars; Thijs, Lutgarde; Gueyffier, François
2017-11-01
To construct a sudden death risk score specifically for hypertension (HYSUD) patients with or without cardiovascular history. Data were collected from six randomized controlled trials of antihypertensive treatments with 8044 women and 17 604 men differing in age ranges and blood pressure eligibility criteria. In total, 345 sudden deaths (1.35%) occurred during a mean follow-up of 5.16 years. Risk factors of sudden death were examined using a multivariable Cox proportional hazards model adjusted on trials. The model was transformed to an integer system, with points added for each factor according to its association with sudden death risk. Antihypertensive treatment was not associated with a reduction of the sudden death risk and had no interaction with other factors, allowing model development on both treatment and placebo groups. A risk score of sudden death in 5 years was built with seven significant risk factors: age, sex, SBP, serum total cholesterol, cigarette smoking, diabetes, and history of myocardial infarction. In terms of discrimination performance, HYSUD model was adequate with areas under the receiver operating characteristic curve of 77.74% (confidence interval 95%, 74.13-81.35) for the derivation set, of 77.46% (74.09-80.83) for the validation set, and of 79.17% (75.94-82.40) for the whole population. Our work provides a simple risk-scoring system for sudden death prediction in hypertension, using individual data from six randomized controlled trials of antihypertensive treatments. HYSUD score could help assessing a hypertensive individual's risk of sudden death and optimizing preventive therapeutic strategies for these patients.
Preprohypocretin polymorphisms in Parkinson disease patients reporting "sleep attacks".
Rissling, Ida; Körner, Yvonne; Geller, Frank; Stiasny-Kolster, Karin; Oertel, Wolfgang H; Möller, J Carsten
2005-07-01
Previously, we found a significant association between the dopamine D2 receptor gene polymorphism Taq IA and sudden onset of sleep in patients with Parkinson disease. Here we evaluated the association between the preprohypocretin (-909T/C), (-22C/T), and (-20C/A) polymorphisms and sudden onset of sleep in the same population of patients with Parkinson disease. We conducted an association study analyzing the distribution of preprohypocretin polymorphisms in Germanic, caucasian Parkinson disease patients with and without sudden onset of sleep, matched according to drug therapy, disease duration, sex, and age. Movement disorders section at a university hospital. 132 Parkinson disease patients with sudden onset of sleep and 132 Parkinson disease patients without sudden onset of sleep. Blood samples were taken from each participant and used for DNA extraction. Polymorphisms were analyzed by established polymerase chain reaction protocols or direct sequencing. The variant allele T of the (-909T/C) preprohypocretin polymorphism was more commonly found in Parkinson disease patients with sudden onset of sleep. Statistical analysis showed that there were significant differences in the genotype (P = .024) and allele (P = .018) distribution between both groups. For heterozygous and homozygous carriers of allele T, the genotype relative-risk estimates for the presence of sudden onset of sleep were 2.01 (95% confidence interval: 0.76-5.34) and 2.81 (95% confidence interval: 1.09-7.25), respectively. Our results show a significant association between the (-909T/C) preprohypocretin polymorphism and sudden onset of sleep in Parkinson disease. However, we could not demonstrate any interaction between the Taq IA and (-909T/C) polymorphisms with respect to the occurrence of sudden onset of sleep, suggesting that multiple genetic factors may contribute to the pathogenesis of this phenomenon.
Next-Generation X-Ray Astronomy
NASA Technical Reports Server (NTRS)
White, Nicholas E.
2011-01-01
The future timing capabilities in X-ray astronomy will be reviewed. This will include reviewing the missions in implementation: Astro-H, GEMS, SRG, and ASTROSAT; those under study: currently ATHENA and LOFT; and new technologies that may enable future missions e.g. Lobster eye optics. These missions and technologies will bring exciting new capabilities across the entire time spectrum from micro-seconds to years that e.g. will allow us to probe close to the event horizon of black holes and constrain the equation of state of neutron stars.
High-quality lossy compression: current and future trends
NASA Astrophysics Data System (ADS)
McLaughlin, Steven W.
1995-01-01
This paper is concerned with current and future trends in the lossy compression of real sources such as imagery, video, speech and music. We put all lossy compression schemes into common framework where each can be characterized in terms of three well-defined advantages: cell shape, region shape and memory advantages. We concentrate on image compression and discuss how new entropy constrained trellis-based compressors achieve cell- shape, region-shape and memory gain resulting in high fidelity and high compression.
Gadelha, Ary; Zugman, André; Calzavara, Mariana Bendlin; de Mendonça Furtado, Remo Holanda; Scorza, Fulvio Alexandre; Bressan, Rodrigo Afonsecca
2018-01-01
Schizophrenia is associated with an increased mortality from cardiovascular disease. Relatively few studies have assessed the putative association of schizophrenia pathophysiology with sudden death. Low adenosine levels have been associated with schizophrenia. In cardiology, increased mortality among patients with congestive heart failure has been associated with genetic polymorphisms that potentially lead to lower adenosine levels. Thus, we hypothesize that adenosine could link schizophrenia and cardiovascular mortality, with decreased adenosine levels leading to increased vulnerability to hyperexcitability following hypoxic insults, increasing the odds of fatal arrhythmias. Low adenosine levels might also lead to a small increase in overall mortality rates and a major increase in the sudden death rate. This hypothesis paves the way for further investigation of the increased cardiac mortality associated with schizophrenia. Potentially, a better characterization of adenosine-related mechanisms of sudden death in schizophrenia could lead to new evidence of factors leading to sudden death in the general population. Copyright © 2017. Published by Elsevier Ltd.
The molecular autopsy: an indispensable step following sudden cardiac death in the young?
Boczek, Nicole J.; Tester, David J.; Ackerman, Michael J.
2013-01-01
Annually thousands of sudden deaths involving young individuals (< 35 years of age) remain unexplained following a complete medicolegal investigation that includes an 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
Major Life Events as Potential Triggers of Sudden Cardiac Arrest
Wicks, April F; Lumley, Thomas; Lemaitre, Rozenn N; Sotoodehnia, Nona; Rea, Thomas D; McKnight, Barbara; Strogatz, David S; Bovbjerg, Viktor E; Siscovick, David S
2012-01-01
Background We investigated recent loss of or separation from afamily member or friend and risk of sudden cardiac arrest. Methods Our case-crossover study included 490 apparently-healthy married residents of King County, Washington, who suffered sudden cardiac arrest between 1988 and 2005. We compared exposure to spouse-reported family/friend events occurring ≤ 1 month before sudden cardiac arrest with events occurring n the previous 5 months. We evaluated potential effect modification by habitual vigorous physical activity. Results Recent family/friend events were associated with a higher risk of sudden cardiac arrest (odds ratio (OR) = 1.6 [95% confidence interval (CI) = 1.1-2.4]). ORs for cases with and without habitual vigorous physical activity were 1.1 (0.6-2.2) and 2.0 (1.2-3.1), respectively, (interaction P = 0.02). Conclusions These results suggest family/friend events may trigger sudden cardiac arrest and raise the hypothesis that habitual vigorous physical activity may lower susceptibility to these potential triggers. PMID:22415111
Major life events as potential triggers of sudden cardiac arrest.
Wicks, April F; Lumley, Thomas; Lemaitre, Rozenn N; Sotoodehnia, Nona; Rea, Thomas D; McKnight, Barbara; Strogatz, David S; Bovbjerg, Viktor E; Siscovick, David S
2012-05-01
We investigated the risk of sudden cardiac arrest in association with the recent loss of, or separation from, a family member or friend. Our case-crossover study included 490 apparently healthy married residents of King County, Washington, who suffered sudden cardiac arrest between 1988 and 2005. We compared exposure to spouse-reported family/friend events occurring ≤ 1 month before sudden cardiac arrest with events occurring in the previous 5 months. We evaluated potential effect modification by habitual vigorous physical activity. Recent family/friend events were associated with a higher risk of sudden cardiac arrest (odds ratio [OR] = 1.6; 95% confidence interval [CI] = 1.1-2.4). ORs for cases with and without habitual vigorous physical activity were 1.1 (0.6-2.2) and 2.0 (1.2-3.1), respectively (interaction P = 0.02). These results suggest family/friend events may trigger sudden cardiac arrest and raise the hypothesis that habitual vigorous physical activity may lower susceptibility to these potential triggers.
Sudden cardiac death in haemodialysis: clinical epidemiology and mechanisms.
Banerjee, Debasish
Sudden cardiac death, which causes premature loss of lives on haemodialysis of the elderly, youths and even children; cannot be prevented, because the aetiology is poorly understood and effective interventions are yet unknown. Improving our knowledge of mechanisms causing sudden cardiac death in haemodialysis patients may help us to design better interventions; and clinical epidemiology of sudden cardiac death could be an important tool to further guide human and animal studies. This review researches the clinical epidemiology of sudden cardiac death to suggest possible mechanisms, although they require further studies. The research shows how traditional cardiovascular risk factors such as age, diabetes and smoking have an impact; non-traditional risk factors such as inflammation, mineral-bone disease and even uraemia itself have higher impact; and how cardiac structural, functional and electrocardiographic markers predict sudden cardiac death in dialysis patients. More in-depth human and animal studies, guided with existing knowledge, are necessary to better understand the mechanisms and design successful interventions. Copyright © 2016 Elsevier Inc. All rights reserved.
Causes of sudden death in young female military recruits.
Eckart, Robert E; Scoville, Stephanie L; Shry, Eric A; Potter, Robert N; Tedrow, Usha
2006-06-15
This study sought to examine the incidence of sudden death in a large, multiethnic cohort of young women. Approximately 852,300 women entered basic military training from 1977 to 2001. During this period, there were 15 sudden deaths in female recruits (median age 19 years, 73% African-American), occurring at a median of 25 days after arrival for training. Of the sudden deaths, 13 (81%) were due to reasons that may have been cardiac in origin. Presumed arrhythmic sudden death in the setting of a structurally normal heart was seen in 8 recruits (53%), and anomalous coronary origins were found in 2 recruits (13%). The mortality rate was 11.4 deaths per 100,000 recruit-years (95% confidence interval 6.9 to 18.9). The rate was significantly higher for African-American female recruits (risk ratio 10.2, p <0.001). Sudden death with a structurally normal heart was the leading cause of death in female recruits during military training.
Sudden oronasal bleeding in a young child.
Hey, Edmund
2008-10-01
Sudden severe upper-airway obstruction occurring in a hospital setting can sometimes precipitate an episode of acute haemorrhagic pulmonary oedema. A review of 197 published case reports shows that the presenting feature is almost always the sudden appearance of blood stained fluid coming up through the larynx or out through the mouth and nose of an adult or child in obvious respiratory distress. Such overt features are seen in 10-15% of cases of sudden severe, but sub-lethal, upper-airway obstruction. Signs normally appear within minutes once the obstruction is relieved but are occasionally only recognized after 1-4 h. All signs and symptoms usually resolve within 12-24 h. Other causes of acute pulmonary haemorrhage are rare in young children. If what looks like blood is seen in, or coming from, the mouth or nose of a previously healthy young child who has suddenly become distressed and started to struggle for breath, that child has most probably suffered an episode of acute pulmonary oedema, and the commonest precipitating cause is sudden upper-airway obstruction.
Toroidal standing waves excited by a storm sudden commencement - DE 1 observations
NASA Technical Reports Server (NTRS)
Cahill, L. J., Jr.; Lin, N. G.; Engebretson, M. J.; Waite, J. H.; Sugiura, M.
1990-01-01
A 74-nT sudden commencement on July 13, 1982, was observed in the magnetosphere, with instruments on the Dynamics Explorer 1 satellite. Inbound, near L = 4.5, the satellite was located at 1524 magnetic local time and 20 deg magnetic latitude. The sudden commmencement established a strong, east-west oscillation, with 100-s period, which was observed in the magnetic field, the electric field, and the plasma flow velocity records. There was also a compressional component of this 100-s oscillation and a rapidly damped 300-s compressional pulsation. The compressional oscillations may be an evidence of cavity resonances, excited by the sudden commencement. The cavity waves may, in turn, couple to toroidal waves in field line resonance at the satellite location. In addition, the sudden commencement caused the onset of waves with frequencies from 0.1 up to at least 0.5 Hz. The observations are compared with similar reports from earlier pulsations related to sudden commencements.
Sudden cardiac death and sarcoidosis of the heart in a young patient.
Jotterand, Morgane; Grabherr, Silke; Lobrinus, Johannes Alexandre; Michaud, Katarzyna
Sarcoidosis is a granulomatous disease of unknown etiology affecting any organ, microscopically characterized by noncaseating granulomata. Cardiac involvement in sarcoidosis has been reported. It might be symptomatic or not and even revealed by sudden death. Heart conduction system is rarely investigated at autopsy, even in cases of sudden cardiac death. We present a case of a 32-year-old woman who died suddenly. The examination of the heart conduction system revealed a cardiac sarcoidosis that could explain the sudden death. The review of clinical data of the patient revealed some symptoms consistent/in agreement with this hypothesis. Cardiac sarcoidosis remains a diagnostic challenge and can be easily missed, clinically and pathologically. The retrospective analysis of clinical data and autopsy results of fatal and unusual cases might help to better understand sarcoidosis and its clinical presentations. Examination of the cardiac conduction system is crucial in selected cases of sudden cardiac death. Copyright © 2017 Elsevier Inc. All rights reserved.
Nonesterified fatty acids and risk of sudden cardiac death in older adults.
Djoussé, Luc; Biggs, Mary L; Ix, Joachim H; Kizer, Jorge R; Lemaitre, Rozenn N; Sotoodehnia, Nona; Zieman, Susan J; Mozaffarian, Dariush; Tracy, Russell P; Mukamal, Kenneth J; Siscovick, David S
2012-04-01
Although nonesterified fatty acids (NEFA) have been positively associated with coronary heart disease risk factors, limited and inconsistent data are available on the relation between NEFA and sudden cardiac death. Using a prospective design, we studied 4657 older men and women (mean age, 75 years) from the Cardiovascular Health Study (1992-2006) to evaluate the association between plasma NEFA and the risk of sudden cardiac death in older adults. Plasma concentrations of NEFA were measured using established enzymatic methods, and sudden death was adjudicated using medical records, death certificates, proxy interview, and autopsy reports. We used Cox proportional hazard models to estimate multivariable-adjusted relative risks. During a median follow-up of 10.0 years, 221 new cases of sudden cardiac death occurred. In a multivariable model adjusting for age, sex, race, clinic site, alcohol intake, smoking, prevalent coronary heart disease and heart failure, and self-reported health status, relative risks (95% confidence interval) for sudden cardiac death were 1.0 (ref), 1.15 (0.81-1.64), 1.06 (0.72-1.55), and 0.91 (0.60-1.38) across consecutive quartiles of NEFA concentration. In secondary analyses restricted to the first 5 years of follow-up, we also did not observe a statistically significant association between plasma NEFA and sudden cardiac death. Our data do not provide evidence for an association between plasma NEFA measured late in life and the risk of sudden cardiac death in older adults.
Mehboob, Riffat
2017-01-01
Sudden demise of a healthy fetus or a neonate is a very tragic episode in the life of parents. These deaths have been a mystery since ages but still remain unexplained. This review proposes the involvement of trigeminal nerve, neurotransmitter substance P (SP), and its receptor neurokinin 1 (NK-1R) in regulation of cardiorespiratory control in fetuses and newborns. Anomalies and immaturity of neuroregulatory systems such as trigeminal system in medulla oblongata of brainstem may provide a possible mechanism of sudden perinatal deaths. Vulnerable infants are born with respiratory center immaturity which in combination with any stressor such as cold, hypoxia, and smoking may lead to cessation of breathing and ventilatory response. SP/NK-1R may be involved in regulating the ventilatory control in neonates while it is decreased in fetal and adult life in humans, and any alterations from these may lead to irreversible sleep apnea and fatal breathing, ultimately sudden death. This review summarizes the studies performed to highlight the expression of SP or NK-1R in sudden perinatal deaths and proposes the involvement of trigeminal ganglion along with its nerve and SP/NK-1R expression alteration as one of the possible pathophysiological underlying mechanism. However, further studies are required to explore the role of SP, NK-1R, and trigeminal system in the pathogenesis of sudden infant deaths, sudden intrauterine deaths, stillbirths, and sudden deaths later in human life. PMID:28348544
Mehboob, Riffat
2017-01-01
Sudden demise of a healthy fetus or a neonate is a very tragic episode in the life of parents. These deaths have been a mystery since ages but still remain unexplained. This review proposes the involvement of trigeminal nerve, neurotransmitter substance P (SP), and its receptor neurokinin 1 (NK-1R) in regulation of cardiorespiratory control in fetuses and newborns. Anomalies and immaturity of neuroregulatory systems such as trigeminal system in medulla oblongata of brainstem may provide a possible mechanism of sudden perinatal deaths. Vulnerable infants are born with respiratory center immaturity which in combination with any stressor such as cold, hypoxia, and smoking may lead to cessation of breathing and ventilatory response. SP/NK-1R may be involved in regulating the ventilatory control in neonates while it is decreased in fetal and adult life in humans, and any alterations from these may lead to irreversible sleep apnea and fatal breathing, ultimately sudden death. This review summarizes the studies performed to highlight the expression of SP or NK-1R in sudden perinatal deaths and proposes the involvement of trigeminal ganglion along with its nerve and SP/NK-1R expression alteration as one of the possible pathophysiological underlying mechanism. However, further studies are required to explore the role of SP, NK-1R, and trigeminal system in the pathogenesis of sudden infant deaths, sudden intrauterine deaths, stillbirths, and sudden deaths later in human life.
Pitman, Alexandra; Rantell, Khadija; Marston, Louise; King, Michael; Osborn, David
2017-03-09
The sudden death of a friend or relative, particularly by suicide, is a risk factor for suicide. People who experience sudden bereavement report feeling highly stigmatised by the loss, potentially influencing access to support. We assessed whether perceived stigma following sudden bereavement is associated with suicidal thoughts and suicide attempt. We analysed cross-sectional survey data on 3387 young adults bereaved by the sudden death of a close contact. We tested the association of high versus low perceived stigma (on the stigma sub-scale of the Grief Experience Questionnaire) with post-bereavement suicidal ideation and suicide attempt, using random effects logistic regression, adjusting for socio-demographic factors, pre-bereavement psychopathology, and mode of sudden bereavement (natural causes/unnatural causes/suicide). Subjects with high perceived stigma scores were significantly more likely to report post-bereavement suicidal thoughts (adjusted odds ratio (AOR) = 2.74; 95% confidence interval (CI) = 1.93-3.89) and suicide attempt (AOR = 2.73; 95% CI = 2.33-3.18) than those with low stigma scores. People who feel highly stigmatised by a sudden bereavement are at increased risk of suicidal thoughts and suicide attempt, even taking into account prior suicidal behaviour. General practitioners, bereavement counsellors, and others who support people bereaved suddenly, should consider inquiring about perceived stigma, mental wellbeing, and suicidal thoughts, and directing them to appropriate sources of support.
Non-linear intensification of Sahel rainfall as a possible dynamic response to future warming
NASA Astrophysics Data System (ADS)
Schewe, Jacob; Levermann, Anders
2017-07-01
Projections of the response of Sahel rainfall to future global warming diverge significantly. Meanwhile, paleoclimatic records suggest that Sahel rainfall is capable of abrupt transitions in response to gradual forcing. Here we present climate modeling evidence for the possibility of an abrupt intensification of Sahel rainfall under future climate change. Analyzing 30 coupled global climate model simulations, we identify seven models where central Sahel rainfall increases by 40 to 300 % over the 21st century, owing to a northward expansion of the West African monsoon domain. Rainfall in these models is non-linearly related to sea surface temperature (SST) in the tropical Atlantic and Mediterranean moisture source regions, intensifying abruptly beyond a certain SST warming level. We argue that this behavior is consistent with a self-amplifying dynamic-thermodynamical feedback, implying that the gradual increase in oceanic moisture availability under warming could trigger a sudden intensification of monsoon rainfall far inland of today's core monsoon region.
Linear and non-linear Modified Gravity forecasts with future surveys
NASA Astrophysics Data System (ADS)
Casas, Santiago; Kunz, Martin; Martinelli, Matteo; Pettorino, Valeria
2017-12-01
Modified Gravity theories generally affect the Poisson equation and the gravitational slip in an observable way, that can be parameterized by two generic functions (η and μ) of time and space. We bin their time dependence in redshift and present forecasts on each bin for future surveys like Euclid. We consider both Galaxy Clustering and Weak Lensing surveys, showing the impact of the non-linear regime, with two different semi-analytical approximations. In addition to these future observables, we use a prior covariance matrix derived from the Planck observations of the Cosmic Microwave Background. In this work we neglect the information from the cross correlation of these observables, and treat them as independent. Our results show that η and μ in different redshift bins are significantly correlated, but including non-linear scales reduces or even eliminates the correlation, breaking the degeneracy between Modified Gravity parameters and the overall amplitude of the matter power spectrum. We further apply a Zero-phase Component Analysis and identify which combinations of the Modified Gravity parameter amplitudes, in different redshift bins, are best constrained by future surveys. We extend the analysis to two particular parameterizations of μ and η and consider, in addition to Euclid, also SKA1, SKA2, DESI: we find in this case that future surveys will be able to constrain the current values of η and μ at the 2-5% level when using only linear scales (wavevector k < 0 . 15 h/Mpc), depending on the specific time parameterization; sensitivity improves to about 1% when non-linearities are included.
Proceedings of the sudden oak death fifth science symposium
Susan J. Frankel; John T. Kliejunas; Katharine M. Palmieri; Janice M. Alexander
2013-01-01
The Proceedings of the Sudden Oak Death Fifth Science Symposium provides an update on research to address sudden oak death, caused by the exotic, quarantine pathogen, Phytophthora ramorum. Over 60 submissions present national and international investigations covering pathogen biology, biosecurity, genetics, monitoring, fire ecology, and diagnostics...
ERIC Educational Resources Information Center
Tindall, James
Initially an assignment for a library science class, this paper presents various definitions of the current creative writing phenomenon called "sudden fiction" (very short short stories with concise character sketches, and terse tales limited in length to several pages). The paper includes: (1) a list of well regarded sudden fiction…
Protecting Future Biodiversity via Re-allocation of Future Land-use Change Patterns
NASA Astrophysics Data System (ADS)
Chini, L. P.; Hurtt, G. C.; Jantz, S.; Brooks, T.; Leon, C.; Waldhoff, S.; Edmonds, J.
2013-12-01
Future scenarios, such as the Representative Concentration Pathways (RCPs), are typically designed to meet a radiative forcing target while also producing enough food and energy for a growing population. In the assessment process, impacts of these scenarios for other important variables such as biodiversity loss are considered 'downstream', after the future climate has been simulated within Earth System Models. However, the direct land-use impacts associated with future scenarios often have as much impact on these issues as the changing climate; in addition, many different patterns of land-use can result in the same radiative forcing target. In the case of biodiversity loss, one of the greatest contributors to species extinction is the loss of habitat such as primary forest, which is a direct result of land-use change decisions. By considering issues such as the preservation of future biodiversity 'up-front' in the scenario process, we can design a scenario that not only meets a radiative forcing target and feeds a growing planet, but also preserves as much habitat as possible through careful spatial allocation of future land-use change. Our Global Land-use Model (GLM) is used to provide 'harmonized' land-use data for the RCP process. GLM preserves as much information as possible from the Integrated Assessment Models (IAMs) while spatially allocating regional IAM land-use change data, ensuring a continuous transition from historical to future land-use states, and producing annual, gridded (0.5°×0.5°), fractional land-use states and all associated transitions. In this presentation we will present results from new GLM simulations in which land-use change decisions are constrained to meet the mutual goals of protecting important eco-regions (e.g. biodiversity hotspots) from future land-use change, providing enough food and fiber for a growing planet, and remaining consistent with the radiative forcing targets of the future scenarios. Trade-offs between agricultural demand and biodiversity protection were needed in some scenarios, but by constraining the land-use decisions to protect future biodiversity, an estimated 10-25% of species could be saved from loss between 2005 and 2100 (Jantz et al. 2013, in prep).
Microsystems and Nanoscience for Biomedical Applications: A View to the Future
ERIC Educational Resources Information Center
Pilarski, Linda M.; Mehta, Michael D.; Caulfield, Timothy; Kaler, Karan V. I. S.; Backhouse, Christopher J.
2004-01-01
At present there is an enormous discrepancy between our nanotechnological capabilities (particularly our nanobiotechnologies), our social wisdom, and consensus on how to apply them. To date, cost considerations have greatly constrained our application of nanotechnologies. However, novel advances in microsystem platform technologies are about to…
ERIC Educational Resources Information Center
Diemer, Matthew A.
2009-01-01
The formation of future occupational expectations is a critical career-development task for adolescents that has a significant impact on adult occupational attainment. However, sociopolitical barriers constrain the occupational expectations and attainment of poor youth of color. Extant research has suggested that sociopolitical development, the…
Sudden Oak Death - Western (Pest Alert)
Susan Frankel
2002-01-01
Tens of thousands of tanoak (Lithocarpus densiflorus), coast live oak (Quercus agrifolia), California black oak (Quercus kelloggii), Shreve oak (Quercus parvula var. shrevei), and madrone (Arbutus menziesii) have been killed by a newly identified species, Phytophthora ramorum, which causes Sudden Oak Death. Sudden Oak Death was first reported in 1995 in central coastal...
Sudden oak death and Phytophthora ramorum: a summary of the literature
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...
ERIC Educational Resources Information Center
Barnett, Henry L.; And Others
There is a growing body of evidence that Sudden Infant Death Syndrome (SIDS) victims are not completely normal and healthy, as was once believed. A variety of new information from several disciplines strongly suggests that the infant who dies suddenly and unexpectedly may do so because of subtle developmental, neurologic, cardiorespiratory, and…
Athletes at Risk for Sudden Cardiac Death
ERIC Educational Resources Information Center
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…
[Genetics of sudden unexplained death].
Campuzano, Oscar; Allegue, Catarina; Brugada, Ramon
2014-03-20
Sudden unexplained death is defined by death without a conclusive diagnosis after autopsy and it is responsible for a large percentage of sudden deaths. The progressive interaction between genetics and forensics in post-mortem studies has identified inheritable alterations responsible for pathologies associated with arrhythmic sudden death. The genetic diagnosis of the deceased enables the undertaking of preventive measures in family members, many of them asymptomatic but at risk. The implications of this multidisciplinary translational medical approach are complex, requiring the dedication of a specialized team. Copyright © 2013 Elsevier España, S.L. All rights reserved.
Bechtel, Kirsten
2012-10-01
Sudden unexpected infant deaths (SUIDs) are deaths in infants younger than 12 months that occur suddenly, unexpectedly, and without obvious cause in the emergency department (ED). Sudden infant death syndrome, the leading cause of SUID in the United States, is much more common, but fatal child abuse and neglect have been sometimes mistaken for sudden infant death syndrome. The distinction between these 2 entities can only be made after a thorough investigation of the scene, interview of caregivers, and a complete forensic autopsy. Development of ED guidelines for the reporting and evaluation of SUID, in collaboration with the local medical examiner and child death review teams, will enable ED practitioners to collect important information in a compassionate manner that will be valuable to the investigating personnel.
Relationship between sudden natural death and abdominal fat evaluated on postmortem CT scans.
Kaichi, Y; Sakane, H; Higashibori, H; Honda, Y; Tatsugami, F; Baba, Y; Iida, M; Awai, K
2017-06-01
This study examined the association between sudden natural death and abdominal fat using postmortem computed tomography (CT) scans. Postmortem CT images at the umbilical level of 241 subjects were used to measure abdominal areas of subcutaneous- and visceral fat, the rate of visceral fat and the waist circumference. Of the study subjects, 174 died of sudden natural death (130 men and 44 women), and 67 died of different causes (46 men and 21 women). All were between 40 and 75 years of age. Logistic regression analysis was performed to identify independent abdominal parameters associated with sudden natural death. By univariate analysis, the areas of subcutaneous and visceral fat were significantly larger in sudden natural death than who died of different causes (subcutaneous fat, odds ratio [OR] = 1.004, 95% confidence interval [CI] = 1.000-1.007, p = 0.03; visceral fat, OR = 1.008, 95% CI = 1.003-1.013, p < 0.01). Multivariate analysis showed that the area of visceral fat was an independent factor associated with the risk of sudden natural death (OR = 1.008, 95% CI = 1.002-1.015, p = 0.02). Postmortem CT revealed that sudden natural death was related to abdominal fat deposits.
F-MARC: promoting the prevention and management of sudden cardiac arrest in football.
Kramer, Efraim Benjamin; Dvorak, J; Schmied, C; Meyer, T
2015-05-01
Sudden cardiac death is the most common cause of unnatural death in football. To prevent and urgently manage sudden cardiac arrest on the football field-of-play, F-MARC (FIFA Medical and Research Centre) has been fully committed to a programme of research, education, standardisation and practical implementation. This strategy has detected football players at medical risk during mandatory precompetition medical assessments. Additionally, FIFA has (1) sponsored internationally accepted guidelines for the interpretation of an athlete's ECG, (2) developed field-of-play-specific protocols for the recognition, response, resuscitation and removal of a football player having sudden cardiac arrest and (3) introduced and distributed the FIFA medical emergency bag which has already resulted in the successful resuscitation of a football player who had a sudden cardiac arrest on the field-of-play. Recently FIFA, in association with the Institute of Sports and Preventive Medicine in Saarbrücken, Germany, established a worldwide Sudden Death Registry with a view to documenting fatal events on the football field-of-play. These activities by F-MARC are testimony to FIFA's continued commitment to minimising sudden cardiac arrest while playing football. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Supersymmetry searches in GUT models with non-universal scalar masses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cannoni, M.; Gómez, M.E.; Ellis, J.
2016-03-01
We study SO(10), SU(5) and flipped SU(5) GUT models with non-universal soft supersymmetry-breaking scalar masses, exploring how they are constrained by LHC supersymmetry searches and cold dark matter experiments, and how they can be probed and distinguished in future experiments. We find characteristic differences between the various GUT scenarios, particularly in the coannihilation region, which is very sensitive to changes of parameters. For example, the flipped SU(5) GUT predicts the possibility of ∼t{sub 1}−χ coannihilation, which is absent in the regions of the SO(10) and SU(5) GUT parameter spaces that we study. We use the relic density predictions in differentmore » models to determine upper bounds for the neutralino masses, and we find large differences between different GUT models in the sparticle spectra for the same LSP mass, leading to direct connections of distinctive possible experimental measurements with the structure of the GUT group. We find that future LHC searches for generic missing E{sub T}, charginos and stops will be able to constrain the different GUT models in complementary ways, as will the Xenon 1 ton and Darwin dark matter scattering experiments and future FERMI or CTA γ-ray searches.« less
Probing the Higgs with angular observables at future e +e – colliders
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Zhen
In this paper, I summarize our recent works on using differential observables to explore the physics potential of future e +e – colliders in the framework of Higgs effective field theory. This proceeding is based upon Refs. 1 and 2. We study angular observables in the e +e – → ZHℓ +ℓ –bmore » $$\\bar{b}$$ channel at future circular e +e – colliders such as CEPC and FCC-ee. Taking into account the impact of realistic cut acceptance and detector effects, we forecast the precision of six angular asymmetries at CEPC (FCC-ee) with center-of-mass energy √s = 240 GeV and 5 (30) ab –1 integrated luminosity. We then determine the projected sensitivity to a range of operators relevant for the Higgsstrahlung process in the dimension-6 Higgs EFT. Our results show that angular observables provide complementary sensitivity to rate measurements when constraining various tensor structures arising from new physics. We further find that angular asymmetries provide a novel means of constraining the “blind spot” in indirect limits on supersymmetric scalar top partners. Finally, we also discuss the possibility of using ZZ-fusion at e +e – machines at different energies to probe new operators.« less
Probing the Higgs with angular observables at future e +e – colliders
Liu, Zhen
2016-10-24
In this paper, I summarize our recent works on using differential observables to explore the physics potential of future e +e – colliders in the framework of Higgs effective field theory. This proceeding is based upon Refs. 1 and 2. We study angular observables in the e +e – → ZHℓ +ℓ –bmore » $$\\bar{b}$$ channel at future circular e +e – colliders such as CEPC and FCC-ee. Taking into account the impact of realistic cut acceptance and detector effects, we forecast the precision of six angular asymmetries at CEPC (FCC-ee) with center-of-mass energy √s = 240 GeV and 5 (30) ab –1 integrated luminosity. We then determine the projected sensitivity to a range of operators relevant for the Higgsstrahlung process in the dimension-6 Higgs EFT. Our results show that angular observables provide complementary sensitivity to rate measurements when constraining various tensor structures arising from new physics. We further find that angular asymmetries provide a novel means of constraining the “blind spot” in indirect limits on supersymmetric scalar top partners. Finally, we also discuss the possibility of using ZZ-fusion at e +e – machines at different energies to probe new operators.« less
Zika Virus Infection and Microcephaly: Evidence for a Causal Link.
Wang, Jin-Na; Ling, Feng
2016-10-20
Zika virus (ZIKV) is a flavivirus related to the Dengue, yellow fever and West Nile viruses. Since the explosive outbreaks of ZIKV in Latin America in 2015, a sudden increase in the number of microcephaly cases has been observed in infants of women who were pregnant when they contracted the virus. The severity of this condition raises grave concerns, and extensive studies on the possible link between ZIKV infection and microcephaly have been conducted. There is substantial evidence suggesting that there is a causal link between ZIKV and microcephaly, however, future studies are warranted to solidify this association. To summarize the most recent evidence on this issue and provide perspectives for future studies, we reviewed the literature to identify existing evidence of the causal link between ZIKV infection and microcephaly within research related to the epidemics, laboratory diagnosis, and possible mechanisms.
Surviving Sudden Cardiac Arrest: A Pilot Qualitative Survey Study of Survivors.
Sawyer, Kelly N; Brown, Frances; Christensen, Roxanne; Damino, Colleen; Newman, Mary M; Kurz, Michael C
2016-06-01
Research describing survivors of sudden cardiac arrest (SCA) has centered on quantifying functional ability, perceived quality of life, and neurocognitive assessment. Many gaps remain, however, regarding survivors' psychosocial perceptions of life in the aftermath of cardiac arrest. An important influence upon those perceptions is the presence of support and its role in a survivor's life. An Internet-based pilot survey study was conducted to gather data from SCA survivors and friends and/or family members (FFMs) representing their support system. The survey was distributed to members of the Sudden Cardiac Arrest Foundation (SCAF) via the Internet by SCAF leadership. Questions included both discrete multiple-choice and open-ended formats. Inductive thematic analyses were completed by three independent researchers trained in qualitative research methodology to identify primary themes consistent among study participants until thematic saturation was achieved. No statistical inferences were made. A total of 205 surveys were returned over the 5-month study period (July to November 2013); nine were received blank, leaving 196 surveys available for review. Major themes identified for survivors (N = 157) include the significance of and desire to share experiences with others; subculture identification (unique experience from those suffering a heart attack); and the need to seek a new normal, both personally and inter-personally. Major themes identified for FFMs (N = 39) include recognition of loved one's memory loss; a lack of information at discharge, including expectations after discharge; and concern for the patient experiencing another cardiac arrest. This pilot, qualitative survey study suggests several common themes important to survivors, and FFMs, of cardiac arrest. These themes may serve as a basis for future patient-centered focus groups and the development of patient-centered guidelines for patients and support persons of those surviving cardiac arrest.
Do prescription stimulants increase the risk of adverse cardiovascular events?: A systematic review
2012-01-01
Background There is increasing concern that prescription stimulants may be associated with adverse cardiovascular events such as stroke, myocardial infarction, and sudden death. Public health concerns are amplified by increasing use of prescription stimulants among adults. Methods The objective of this study was to conduct a systematic review of the evidence of an association between prescription stimulant use and adverse cardiovascular outcomes. PUBMED, MEDLINE, EMBASE and Google Scholar searches were conducted using key words related to these topics (MESH): ADHD; Adults; Amphetamine; Amphetamines; Arrhythmias, Cardiac; Cardiovascular Diseases; Cardiovascular System; Central Nervous Stimulants; Cerebrovascular; Cohort Studies; Case–control Studies; Death; Death, Sudden, Cardiac; Dextroamphetamine; Drug Toxicity; Methamphetamine; Methylphenidate; Myocardial Infarction; Stimulant; Stroke; Safety. Eligible studies were population-based studies of children, adolescents, or adults using prescription stimulant use as the independent variable and a hard cardiovascular outcome as the dependent variable. Results Ten population-based observational studies which evaluated prescription stimulant use with cardiovascular outcomes were reviewed. Six out of seven studies in children and adolescents did not show an association between stimulant use and adverse cardiovascular outcomes. In contrast, two out of three studies in adults found an association. Conclusions Findings of an association between prescription stimulant use and adverse cardiovascular outcomes are mixed. Studies of children and adolescents suggest that statistical power is limited in available study populations, and the absolute risk of an event is low. More suggestive of a safety signal, studies of adults found an increased risk for transient ischemic attack and sudden death/ventricular arrhythmia. Interpretation was limited due to differences in population, cardiovascular outcome selection/ascertainment, and methodology. Accounting for confounding and selection biases in these studies is of particular concern. Future studies should address this and other methodological issues. PMID:22682429
Claus, Andrew P; Verrel, Julius; Pounds, Paul E I; Shaw, Renee C; Brady, Niamh; Chew, Min T; Dekkers, Thomas A; Hodges, Paul W
2016-05-03
Sudden application of load along a sagittal or coronal axis has been used to study trunk stiffness, but not axial (vertical) load. This study introduces a new method for sudden-release axial load perturbation. Prima facie validity was supported by comparison with standard mechanical systems. We report the response of the human body to axial perturbation in sitting and standing and within-day repeatability of measures. Load of 20% of body weight was released from light contact onto the shoulders of 22 healthy participants (10 males). Force input was measured via force transducers at shoulders, output via a force plate below the participant, and kinematics via 3-D motion capture. System identification was used to fit data from the time of load release to time of peak load-displacement, fitting with a 2nd-order mass-spring-damper system with a delay term. At peak load-displacement, the mean (SD) effective stiffness measured with this device for participants in sitting was 12.0(3.4)N/mm, and in standing was 13.3(4.2)N/mm. Peak force output exceeded input by 44.8 (10.0)% in sitting and by 30.4(7.9)% in standing. Intra-class correlation coefficients for within-day repeatability of axial stiffness were 0.58 (CI: -0.03 to 0.83) in sitting and 0.82(0.57-0.93) in standing. Despite greater degrees of freedom in standing than sitting, standing involved lesser time, downward displacement, peak output force and was more repeatable in defending upright postural control against the same axial loads. This method provides a foundation for future studies of neuromuscular control with axial perturbation. Copyright © 2016 Elsevier Ltd. All rights reserved.
Quantifying the Spatial and Temporal Properties of Microbursts with Multi-spacecraft Missions
NASA Astrophysics Data System (ADS)
Shumko, M.; Turner, D. L.; Sample, J. G.; O'Brien, T. P., III; Claudepierre, S. G.; Fennell, J. F.; Johnson, A.; Blake, J. B.; Agapitov, O. V.; Crew, A. B.; Klumpar, D. M.; Spence, H. E.
2017-12-01
The outer electron Van Allen radiation belt is highly variable, and is at times, depleted on the order of one day or less. One loss mechanism potentially capable of depleting the belts on such timescales is electron microbursts, a sporadic and sudden burst of electrons, routinely observed in Low Earth Orbit (LEO). To quantify their contribution to radiation belt electron loss, their spatio-temporal morphology must be well characterized and constrained. These properties can be investigated by multi-spacecraft missions e.g. Focused Investigations of Relativistic Electron Burst Intensity, Range, and Dynamics (FIREBIRD-II), AeroCube 6 (AC6) and the Van Allen Probes (VAP). We present results of microburst scale sizes derived using FIREBIRD-II and AC-6 CubeSats pairs. In addition, we present results of a conjunction between AC6 and VAP at L 5. Lower band chorus was observed by the EMFISIS instrument, while microbursts were observed with its MagEIS instrument, and AC6 in LEO. We believe that this MagEIS observation is the first known measurement of an electron microburst outside of LEO.
Snap-buckling in asymmetrically constrained elastic strips
NASA Astrophysics Data System (ADS)
Sano, Tomohiko G.; Wada, Hirofumi
2018-01-01
When a flat elastic strip is compressed along its axis, it is bent in one of two possible directions via spontaneous symmetry breaking, forming a cylindrical arc. This is a phenomenon well known as Euler buckling. When this cylindrical section is pushed in the other direction, the bending direction can suddenly reverse. This instability is called "snap-through buckling" and is one of the elementary shape transitions in a prestressed thin structure. Combining experiments and theory, we study snap-buckling of an elastic strip with one end hinged and the other end clamped. These asymmetric boundary constraints break the intrinsic symmetry of the strip, generating mechanical behaviors, including largely hysteretic but reproducible force responses and switchlike discontinuous shape changes. We establish the set of exact analytical solutions to fully explain all our major experimental and numerical findings. Asymmetric boundary conditions arise naturally in diverse situations when a thin object is in contact with a solid surface at one end. The introduction of asymmetry through boundary conditions yields new insight into complex and programmable functionalities in material and industrial design.
Constraining Light-Quark Yukawa Couplings from Higgs Distributions.
Bishara, Fady; Haisch, Ulrich; Monni, Pier Francesco; Re, Emanuele
2017-03-24
We propose a novel strategy to constrain the bottom and charm Yukawa couplings by exploiting Large Hadron Collider (LHC) measurements of transverse momentum distributions in Higgs production. Our method does not rely on the reconstruction of exclusive final states or heavy-flavor tagging. Compared to other proposals, it leads to an enhanced sensitivity to the Yukawa couplings due to distortions of the differential Higgs spectra from emissions which either probe quark loops or are associated with quark-initiated production. We derive constraints using data from LHC run I, and we explore the prospects of our method at future LHC runs. Finally, we comment on the possibility of bounding the strange Yukawa coupling.
Constraining Light-Quark Yukawa Couplings from Higgs Distributions
NASA Astrophysics Data System (ADS)
Bishara, Fady; Haisch, Ulrich; Monni, Pier Francesco; Re, Emanuele
2017-03-01
We propose a novel strategy to constrain the bottom and charm Yukawa couplings by exploiting Large Hadron Collider (LHC) measurements of transverse momentum distributions in Higgs production. Our method does not rely on the reconstruction of exclusive final states or heavy-flavor tagging. Compared to other proposals, it leads to an enhanced sensitivity to the Yukawa couplings due to distortions of the differential Higgs spectra from emissions which either probe quark loops or are associated with quark-initiated production. We derive constraints using data from LHC run I, and we explore the prospects of our method at future LHC runs. Finally, we comment on the possibility of bounding the strange Yukawa coupling.
Spectrum and orbit conservation as a factor in future mobile satellite system design
NASA Technical Reports Server (NTRS)
Bowen, Robert R.
1990-01-01
Access to the radio spectrum and geostationary orbit is essential to current and future mobile satellite systems. This access is difficult to obtain for current systems, and may be even more so for larger future systems. In this environment, satellite systems that minimize the amount of spectrum orbit resource required to meet a specific traffic requirement are essential. Several spectrum conservation techniques are discussed, some of which are complementary to designing the system at minimum cost. All may need to be implemented to the limits of technological feasibility if network growth is not to be constrained because of the lack of available spectrum-orbit resource.
Elucidating dark energy with future 21 cm observations at the epoch of reionization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kohri, Kazunori; Oyama, Yoshihiko; Sekiguchi, Toyokazu
2017-02-01
We investigate how precisely we can determine the nature of dark energy such as the equation of state (EoS) and its time dependence by using future observations of 21 cm fluctuations at the epoch of reionization (06.8∼< z ∼<1) such as Square Kilometre Array (SKA) and Omniscope in combination with those from cosmic microwave background, baryon acoustic oscillation, type Ia supernovae and direct measurement of the Hubble constant. We consider several parametrizations for the EoS and find that future 21 cm observations will be powerful in constraining models of dark energy, especially when its EoS varies at high redshifts.
Space ventures and society long-term perspectives
NASA Technical Reports Server (NTRS)
Brown, W. M.
1985-01-01
A futuristic evaluation of mankind's potential long term future in space is presented. Progress in space will not be inhibited by shortages of the Earth's physical resources, since long term economic growth will be focused on ways to constrain industrial productivity by changing social values, management styles, or government competence. Future technological progress is likely to accelerate with an emphasis on international cooperation, making possible such large joint projects as lunar colonies or space stations on Mars. The long term future in space looks exceedingly bright even in relatively pessimistic scenarios. The principal driving forces will be technological progress, commercial and public-oriented satellites, space industrialization, space travel, and eventually space colonization.
NASA Technical Reports Server (NTRS)
Burkhardt, Z.; Ramachandran, N.; Majumdar, A.
2017-01-01
Fluid Transient analysis is important for the design of spacecraft propulsion system to ensure structural stability of the system in the event of sudden closing or opening of the valve. Generalized Fluid System Simulation Program (GFSSP), a general purpose flow network code developed at NASA/MSFC is capable of simulating pressure surge due to sudden opening or closing of valve when thermodynamic properties of real fluid are available for the entire range of simulation. Specifically GFSSP needs an accurate representation of pressure-density relationship in order to predict pressure surge during a fluid transient. Unfortunately, the available thermodynamic property programs such as REFPROP, GASP or GASPAK does not provide the thermodynamic properties of Monomethylhydrazine (MMH). This paper will illustrate the process used for building a customized table of properties of state variables from available properties and speed of sound that is required by GFSSP for simulation. Good agreement was found between the simulations and measured data. This method can be adopted for modeling flow networks and systems with other fluids whose properties are not known in detail in order to obtain general technical insight. Rigorous code validation of this approach will be done and reported at a future date.
Temporal Epidemiology of Sudden Oak Death in Oregon.
Peterson, Ebba K; Hansen, Everett M; Kanaskie, Alan
2015-07-01
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 precipitation 2 years before detection, and infestation size the year prior. Infestation size was best modeled by infestation size and spring precipitation the year prior. In our interpretation, there is a 2-year delay between the introduction of inoculum and onset of mortality for a majority of sites. The year-long gap in between allows ample time for the production of inoculum contributing to the spread of P. ramorum. This is supported by epidemic development following changes in eradication protocols precipitated by an outbreak in 2011, attributable to a 2009 treatment delay and an uncharacteristically wet spring in 2010. Posteradication, we have observed an increase in the total area of new outbreaks and increased frequency in dispersal distances greater than 4 km. Although the eradication program has not eliminated P. ramorum from Oregon forests, it has likely moderated this epidemic, emphasizing the need for prompt treatment of future invasive forest pathogens.
Rong-Min Chen, R M
1995-02-01
It has been hypothesised that change in the family environment affects short-term recovery from schizophrenia. Observation and study of 210 schizophrenic patients who were influenced by family environmental alteration show that the prognosis of schizophrenia caused suddenly by family environmental alteration is better than that of schizophrenia caused by a persistently unfavourable family environment. Hence, we think sudden family environmental alterations do not cause psychorrhoea, but slow family environmental alteration may cause change in the mental state of patients. The prognosis is worse in the countryside than in the city. From the study group, we conclude that the first cure rate was 28%, and that 26% of patients were able to work. This indicates that there were no typical cases of the core pattern of schizophrenia, and that there was a certain potential for recovery. In the future, the emphasis of prevention and treatment must be placed on the countryside, and attention should be paid to the improvement of living and working conditions there, to the correct administration of patients, and to the improvement of recovery measures and therapy. We advocate that efforts should be made in the countryside to raise the national educational and cultural level.
Development of a microfluidic perfusion 3D cell culture system
NASA Astrophysics Data System (ADS)
Park, D. H.; Jeon, H. J.; Kim, M. J.; Nguyen, X. D.; Morten, K.; Go, J. S.
2018-04-01
Recently, 3-dimensional in vitro cell cultures have gained much attention in biomedical sciences because of the closer relevance between in vitro cell cultures and in vivo environments. This paper presents a microfluidic perfusion 3D cell culture system with consistent control of long-term culture conditions to mimic an in vivo microenvironment. It consists of two sudden expansion reservoirs to trap incoming air bubbles, gradient generators to provide a linear concentration, and microchannel mixers. Specifically, the air bubbles disturb a flow in the microfluidic channel resulting in the instability of the perfusion cell culture conditions. For long-term stable operation, the sudden expansion reservoir is designed to trap air bubbles by using buoyancy before they enter the culture system. The performance of the developed microfluidic perfusion 3D cell culture system was examined experimentally and compared with analytical results. Finally, it was applied to test the cytotoxicity of cells infected with Ewing’s sarcoma. Cell death was observed for different concentrations of H2O2. For future work, the developed microfluidic perfusion 3D cell culture system can be used to examine the behavior of cells treated with various drugs and concentrations for high-throughput drug screening.
Sudden Cardiac Arrest during Participation in Competitive Sports.
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 arrest during participation in competitive sports was 0.76 cases per 100,000 athlete-years. The occurrence of sudden cardiac arrest due to structural heart disease was uncommon during participation in competitive sports. (Funded by the National Heart, Lung, and Blood Institute and others.).
Optimizing future imaging survey of galaxies to confront dark energy and modified gravity models
NASA Astrophysics Data System (ADS)
Yamamoto, Kazuhiro; Parkinson, David; Hamana, Takashi; Nichol, Robert C.; Suto, Yasushi
2007-07-01
We consider the extent to which future imaging surveys of galaxies can distinguish between dark energy and modified gravity models for the origin of the cosmic acceleration. Dynamical dark energy models may have similar expansion rates as models of modified gravity, yet predict different growth of structure histories. We parametrize the cosmic expansion by the two parameters, w0 and wa, and the linear growth rate of density fluctuations by Linder’s γ, independently. Dark energy models generically predict γ≈0.55, while the Dvali-Gabadadze-Porrati (DGP) model γ≈0.68. To determine if future imaging surveys can constrain γ within 20% (or Δγ<0.1), we perform the Fisher matrix analysis for a weak-lensing survey such as the ongoing Hyper Suprime-Cam (HSC) project. Under the condition that the total observation time is fixed, we compute the figure of merit (FoM) as a function of the exposure time texp. We find that the tomography technique effectively improves the FoM, which has a broad peak around texp≃several˜10min; a shallow and wide survey is preferred to constrain the γ parameter. While Δγ<0.1 cannot be achieved by the HSC weak-lensing survey alone, one can improve the constraints by combining with a follow-up spectroscopic survey like Wide-field Fiber-fed Multi-Object Spectrograph (WFMOS) and/or future cosmic microwave background (CMB) observations.
Afterglow model for the radio emission from the jetted tidal disruption candidate Swift J1644+57
NASA Astrophysics Data System (ADS)
Metzger, Brian D.; Giannios, Dimitrios; Mimica, Petar
2012-03-01
The recent transient event Swift J1644+57 has been interpreted as emission from a collimated relativistic jet, powered by the sudden onset of accretion on to a supermassive black hole following the tidal disruption of a star. Here we model the radio-microwave emission as synchrotron radiation produced by the shock interaction between the jet and the gaseous circumnuclear medium (CNM). At early times after the onset of the jet (t≲ 5-10 d) a reverse shock propagates through and decelerates the ejecta, while at later times the outflow approaches the Blandford-McKee self-similar evolution (possibly modified by additional late energy injection). The achromatic break in the radio light curve of Swift J1644+57 is naturally explained as the transition between these phases. We show that the temporal indices of the pre- and post-break light curve are consistent with those predicted if the CNM has a wind-type radial density profile n∝r-2. The observed synchrotron frequencies and self-absorbed flux constrain the fraction of the post-shock thermal energy in relativistic electrons ɛe≈ 0.03-0.1, the CNM density at 1018 cm n18≈ 1-10 cm-3 and the initial Lorentz factor Γj≈ 10-20 and opening angle ? of the jet. Radio modelling thus provides robust independent evidence for a narrowly collimated outflow. Extending our model to the future evolution of Swift J1644+57, we predict that the radio flux at low frequencies (ν≲ few GHz) will begin to brighten more rapidly once the characteristic frequency νm crosses below the radio band after it decreases below the self-absorption frequency on a time-scale of months (indeed, such a transition may already have begun). Our results demonstrate that relativistic outflows from tidal disruption events provide a unique probe of the conditions in distant, previously inactive galactic nuclei, complementing studies of normal active galactic nuclei.
Eruptive Source Parameters from Near-Source Gravity Waves Induced by Large Vulcanian eruptions
NASA Astrophysics Data System (ADS)
Barfucci, Giulia; Ripepe, Maurizio; De Angelis, Silvio; Lacanna, Giorgio; Marchetti, Emanuele
2016-04-01
The sudden ejection of hot material from volcanic vent perturbs the atmosphere generating a broad spectrum of pressure oscillations from acoustic infrasound (<10 Hz) to gravity waves (<0.03 Hz). However observations of gravity waves excited by volcanic eruptions are still rare, mostly limited to large sub-plinian eruptions and frequently at large distance from the source (>100 km). Atmospheric Gravity waves are induced by perturbations of the hydrostatic equilibrium of the atmosphere and propagate within a medium with internal density stratification. They are initiated by mechanisms that cause the atmosphere to be displaced as for the injection of volcanic ash plume during an eruption. We use gravity waves to infer eruptive source parameters, such as mass eruption rate (MER) and duration of the eruption, which may be used as inputs in the volcanic ash transport and dispersion models. We present the analysis of near-field observations (<7 km) of atmospheric gravity waves, with frequencies of 0.97 and 1.15 mHz, recorded by a pressure sensors network during two explosions in July and December 2008 at Soufrière Hills Volcano, Montserrat. We show that gravity waves at Soufrière Hills Volcano originate above the volcanic dome and propagate with an apparent horizontal velocities of 8-10 m/s. Assuming a single mass injection point source model, we constrain the source location at ~3.5 km a.s.l., above the vent, duration of the gas thrust < 140 s and MERs of 2.6 and 5.4 x10E7 kg/s, for the two eruptive events. Source duration and MER derived by modeling Gravity Waves are fully compatible with others independent estimates from field observations. Our work strongly supports the use of gravity waves to model eruption source parameters and can have a strong impact on our ability to monitor volcanic eruption at a large distance and may have future application in assessing the relative magnitude of volcanic explosions.
Stojanovska, Jadranka; Garg, Anubhav; Patel, Smita; Melville, David M; Kazerooni, Ella A; Mueller, Gisela C
2013-01-01
Sudden cardiac death is defined as death from unexpected circulatory arrest-usually a result of cardiac arrhythmia-that occurs within 1 hour of the onset of symptoms. Proper and timely identification of individuals at risk for sudden cardiac death and the diagnosis of its predisposing conditions are vital. A careful history and physical examination, in addition to electrocardiography and cardiac imaging, are essential to identify conditions associated with sudden cardiac death. Among young adults (18-35 years), sudden cardiac death most commonly results from a previously undiagnosed congenital or hereditary condition, such as coronary artery anomalies and inherited cardiomyopathies (eg, hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy [ARVC], dilated cardiomyopathy, and noncompaction cardiomyopathy). Overall, the most common causes of sudden cardiac death in young adults are, in descending order of frequency, hypertrophic cardiomyopathy, coronary artery anomalies with an interarterial or intramural course, and ARVC. Often, sudden cardiac death is precipitated by ventricular tachycardia or fibrillation and may be prevented with an implantable cardioverter defibrillator (ICD). Risk stratification to determine the need for an ICD is challenging and involves imaging, particularly echocardiography and cardiac magnetic resonance (MR) imaging. Coronary artery anomalies, a diverse group of congenital disorders with a variable manifestation, may be depicted at coronary computed tomographic angiography or MR angiography. A thorough understanding of clinical risk stratification, imaging features, and complementary diagnostic tools for the evaluation of cardiac disorders that may lead to sudden cardiac death is essential to effectively use imaging to guide diagnosis and therapy.
Ward, Peter L.; Page, Robert A.
1990-01-01
The San Andreas fault, in California, is the primary boundary between the North American plate and the Pacific plate. Land west of the fault has been moving northwestward relative to land on the east at an average rate of 2 inches per year for millions of years. This motion is not constant but occurs typically in sudden jumps during large earthquakes. This motion is relentless; therefore earthquakes in California are inevitable.
Evaluation of factor IX deficiency by interdigitated electrode (IDE)
NASA Astrophysics Data System (ADS)
Gopinath, Subash C. B.; Hashim, Uda; Uda, M. N. A.
2017-03-01
Factor IX deficiency is the main cause of hemophilia A and B. This a severe excessive bleeding disorder that can even kill the patient if not treated with the right prescription of Factor IX hormone to stop the bleeding. The bleeding can be caused by an injury or even a sudden bleeding in some very rare cases. To find the Factor IX effectiveness and to understand the deficiency more carefully for the future of medicine, experiments are conducted to test the Factor IX using the Interdigitated Electrode (IDE) and gold Nanoparticle with the help of Nanoelectrical technology.
Non-locality Sudden Death in Tripartite Systems
NASA Astrophysics Data System (ADS)
Jaeger, Gregg; Ann, Kevin
2009-03-01
Bell non-locality sudden death is the disappearance of non-local properties in finite times under local phase noise, which decoheres states only in the infinite-time limit. We consider the relationship between decoherence, disentanglement, and Bell non-locality sudden death in bipartite and tripartite systems in specific large classes of state preparation.
77 FR 69485 - Proposed Data Collections Submitted for Public Comment and Recommendations
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-19
... days of this notice. Proposed Project Determining Causes of Sudden, Unexpected Infant Death: A National... immediately obvious. Half of these sudden unexpected infant deaths (SUID) are attributed to Sudden Infant Death Syndrome (SIDS), which is the leading cause of death in infants between one and twelve months of...
Exercise-Related Sudden Death: Risks and Causes (Part 1 of 2).
ERIC Educational Resources Information Center
Van Camp, Steven P.
1988-01-01
The causes of exercise-related sudden death are discussed. Multiple structural cardiovascular diseases are the primary cause of death in athletes under 30; severe coronary artery disease is the culprit in deaths of those over 30. These diseases and the mechanisms of sudden death, as well as preventive measures, are detailed. (JL)
NASA Astrophysics Data System (ADS)
Cheng, Jianbo; Min, Li; Zheng, Nan; Fan, Caiyun; Zhao, Shengguo; Zhang, Yangdong; Wang, Jiaqi
2018-02-01
This study was designed to investigate the effects of sudden cooling on the physiological responses of 12 heat-stressed Holstein dairy cows using an isobaric tags for relative and absolute quantification (iTRAQ) labeling approach. Plasma samples were collected from these cows during heat stress (HS), and after strong, sudden cooling in the summer (16 days later). We compared plasma proteomic data before and after sudden cooling to identify the differentially abundant proteins. The results showed that sudden cooling in summer effectively alleviated the negative consequences of HS on body temperature and production variables. Expressions of plasma hemoglobin alpha and hemoglobin beta were upregulated, whereas lipopolysaccharide-binding protein (LBP) and haptoglobin were downregulated in this process. The increase of hemoglobin after cooling may improve oxygen transport and alleviate the rise in respiration rates in heat-stressed dairy cows. The decrease of LBP and haptoglobin suggests that the inflammatory responses caused by HS are relieved after cooling. Our findings provide new insight into the physiological changes that occur when heat-stressed dairy cows experience strong, sudden cooling.
Recent advances in understanding and prevention of sudden cardiac death.
Vandenberg, Jamie I; Perry, Matthew D; Hill, Adam P
2017-01-01
There have been tremendous advances in the diagnosis and treatment of heart disease over the last 50 years. Nevertheless, it remains the number one cause of death. About half of heart-related deaths occur suddenly, and in about half of these cases the person was unaware that they had underlying heart disease. Genetic heart disease accounts for only approximately 2% of sudden cardiac deaths, but as it typically occurs in younger people it has been a particular focus of activity in our quest to not only understand the underlying mechanisms of cardiac arrhythmogenesis but also develop better strategies for earlier detection and prevention. In this brief review, we will highlight trends in the recent literature focused on sudden cardiac death in genetic heart diseases and how these studies are contributing to a broader understanding of sudden death in the community.
Wood, Angela M; Pasupathy, Dharmintra; Pell, Jill P; Fleming, Michael
2012-01-01
Objectives To compare changes in inequalities in sudden infant death syndrome with other causes of infant mortality and stillbirth in Scotland, 1985-2008. Design Retrospective cohort study. Setting Scotland 1985-2008, analysed by four epochs of six years. Participants Singleton births of infants with birth weight >500 g born at 28-43 weeks’ gestation. Main outcome measures Sudden infant death syndrome, other causes of postneonatal infant death, neonatal death, and stillbirth. Odds ratios expressed as the association across the range of seven categories of Carstairs deprivation score. Results The association between deprivation and the risk of all cause stillbirth and infant death varied between the four epochs (P=0.04). This was wholly explained by variation in the risk of sudden infant death syndrome (P<0.001 for interaction). Among women living in areas of low deprivation, there was a sharp decline in the rate of sudden infant death syndrome from 1990 to 1993. Among women living in areas of high deprivation, there was a slower decline in sudden infant death syndrome rates between 1992 and 2004. Consequently, the odds ratio for the association between socioeconomic deprivation and sudden infant death syndrome increased from 2.04 (95% confidence interval 1.53 to 2.72) in 1985-90, to 7.52 (4.62 to 12.25) in 1991-6, and 9.50 (5.46 to 16.53) in 1997-2002 but fell to 1.78 (0.87 to 3.65) in 2002-8. The interaction remained significant after adjustment for maternal characteristics. Conclusion The rate of sudden infant death syndrome declined throughout Scotland in the early 1990s. The decline had a later onset and was slower among women living in areas of high deprivation, probably because of slower uptake of recommended changes in infant sleeping position. The effect was to create a strong independent association between deprivation and sudden infant death syndrome where one did not exist before. PMID:22427307
Wood, Angela M; Pasupathy, Dharmintra; Pell, Jill P; Fleming, Michael; Smith, Gordon C S
2012-03-16
To compare changes in inequalities in sudden infant death syndrome with other causes of infant mortality and stillbirth in Scotland, 1985-2008. Retrospective cohort study. Scotland 1985-2008, analysed by four epochs of six years. Singleton births of infants with birth weight >500 g born at 28-43 weeks' gestation. Sudden infant death syndrome, other causes of postneonatal infant death, neonatal death, and stillbirth. Odds ratios expressed as the association across the range of seven categories of Carstairs deprivation score. The association between deprivation and the risk of all cause stillbirth and infant death varied between the four epochs (P=0.04). This was wholly explained by variation in the risk of sudden infant death syndrome (P<0.001 for interaction). Among women living in areas of low deprivation, there was a sharp decline in the rate of sudden infant death syndrome from 1990 to 1993. Among women living in areas of high deprivation, there was a slower decline in sudden infant death syndrome rates between 1992 and 2004. Consequently, the odds ratio for the association between socioeconomic deprivation and sudden infant death syndrome increased from 2.04 (95% confidence interval 1.53 to 2.72) in 1985-90, to 7.52 (4.62 to 12.25) in 1991-6, and 9.50 (5.46 to 16.53) in 1997-2002 but fell to 1.78 (0.87 to 3.65) in 2002-8. The interaction remained significant after adjustment for maternal characteristics. The rate of sudden infant death syndrome declined throughout Scotland in the early 1990s. The decline had a later onset and was slower among women living in areas of high deprivation, probably because of slower uptake of recommended changes in infant sleeping position. The effect was to create a strong independent association between deprivation and sudden infant death syndrome where one did not exist before.
Zhou, Jie; Ning, Xiaopeng; Nimbarte, Ashish D; Dai, Fei
2015-01-01
As a major risk factor of low back injury, sudden loading often occurs when performing manual material-handling tasks on uneven ground surfaces. Therefore, the purpose of the current study was to investigate the effects of a laterally slanted ground on trunk biomechanical responses during sudden loading events. Thirteen male subjects were subjected to suddenly released loads of 3.4 and 6.8 kg, while standing on a laterally slanted ground of 0°, 15° and 30°. The results showed that 8.3% and 5.6% larger peak L5/S1 joint compression forces were generated in the 30° condition compared with the 0° and 15° conditions, respectively. The increase of L5/S1 joint moment in the 30° condition was 8.5% and 5.0% greater than the 0° and 15° conditions, respectively. Findings of this study suggest that standing on a laterally slanted ground could increase mechanical loading on the spine when experiencing sudden loading. Practitioner Summary: Sudden loading is closely related to occupational low back injuries. The results of this study showed that the increase of slanted ground angle and magnitude of load significantly increase the mechanical loading on the spine during sudden loading. Therefore, both of these two components should be controlled in task design.
Sudden death in young athletes: HCM or ARVC?
Firoozi, Sam; Sharma, Sanjay; Hamid, M Shoaib; McKenna, William J
2002-01-01
Sudden non-traumatic death in young athletes is due to underlying congenital/inherited cardiac diseases in over 80% of cases. The two commonest conditions leading to sudden cardiac death in athletes below the age of 25 years are hypertrophic cardiomyopathy (HCM) and arrhythmogenic right ventricular cardiomyopathy (ARVC). Hypertrophic cardiomyopathy is caused by mutations in genes, which code for sarcomeric contractile proteins. It can present with symptoms such as palpitation, presyncope or syncope. In a small number of cases, sudden death is the first clinical manifestation of the condition. It is well established that HCM accounts for over half of all cases sudden cardiac death in young individuals below 25 years of age. The management of HCM broadly encompasses symptom control, familial evaluation and the prevention of sudden death. Arrhythmogenic right ventricular cardiomyopathy, similarly, is a genetic disorder of the heart muscle and leads to symptoms such as palpitation and syncope and more rarely sudden death. The diagnosis of ARVC is most likely underestimated due to the lack of a single diagnostic test and subtle morphological changes in some cases. The diagnosis is based on clinical and family history and non-invasive investigations. The physiological adaptations seen in some athletes, as a response to physical training, may resemble phenotypically mild forms HCM and ARVC. Therefore, a diagnostic algorithm enabling this differentiation would be of importance especially bearing in mind the consequences of a misdiagnosis.
Detection of a sudden change of the field time series based on the Lorenz system.
Da, ChaoJiu; Li, Fang; Shen, BingLu; Yan, PengCheng; Song, Jian; Ma, DeShan
2017-01-01
We conducted an exploratory study of the detection of a sudden change of the field time series based on the numerical solution of the Lorenz system. First, the time when the Lorenz path jumped between the regions on the left and right of the equilibrium point of the Lorenz system was quantitatively marked and the sudden change time of the Lorenz system was obtained. Second, the numerical solution of the Lorenz system was regarded as a vector; thus, this solution could be considered as a vector time series. We transformed the vector time series into a time series using the vector inner product, considering the geometric and topological features of the Lorenz system path. Third, the sudden change of the resulting time series was detected using the sliding t-test method. Comparing the test results with the quantitatively marked time indicated that the method could detect every sudden change of the Lorenz path, thus the method is effective. Finally, we used the method to detect the sudden change of the pressure field time series and temperature field time series, and obtained good results for both series, which indicates that the method can apply to high-dimension vector time series. Mathematically, there is no essential difference between the field time series and vector time series; thus, we provide a new method for the detection of the sudden change of the field time series.
Sudden death in eating disorders
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. PMID:22393299
Looking forward: the effects of photographs on the qualities of future thinking.
Bays, Rebecca B; Wellen, Brianna C M; Greenberg, Katherine S
2018-04-01
Future episodic thinking relies on the reconstruction of remembered experiences. Photographs provide one means of remembering, acting as a "cognitive springboard" for generating related memory qualities. We wondered whether photographs would also invite embellishment of future thought qualities, particularly in the presence (or absence) of associated memories. In two studies participants generated future events in familiar (associated memories) and novel (no associated memories) locations. Half of the participants viewed scene location photographs during event generation. All participants then imagined the events for one minute and completed a self-report measure of content qualities. Results of the current set of studies suggested that for novel locations, no differences in qualities emerged; however, for familiar locations, photographs did not enhance qualities and, in some cases, actually constrained perceptual (Experiments 1 and 2) and sensory (Experiment 1) detail ratings of future thoughts. Thus, photographs did not invite embellishment of future thought details.
Evolution of Requirements and Assumptions for Future Exploration Missions
NASA Technical Reports Server (NTRS)
Anderson, Molly; Sargusingh, Miriam; Perry, Jay
2017-01-01
NASA programs are maturing technologies, systems, and architectures to enabling future exploration missions. To increase fidelity as technologies mature, developers must make assumptions that represent the requirements of a future program. Multiple efforts have begun to define these requirements, including team internal assumptions, planning system integration for early demonstrations, and discussions between international partners planning future collaborations. For many detailed life support system requirements, existing NASA documents set limits of acceptable values, but a future vehicle may be constrained in other ways, and select a limited range of conditions. Other requirements are effectively set by interfaces or operations, and may be different for the same technology depending on whether the hard-ware is a demonstration system on the International Space Station, or a critical component of a future vehicle. This paper highlights key assumptions representing potential life support requirements and explanations of the driving scenarios, constraints, or other issues that drive them.
Future energy prices and supply, availability and costs can have a significant impact on how fast and cost effectively we could abate carbon emissions. Two-staged decision making methods embedded in U.S. EPA's MARKAL modeling system will be utilized to find the most robust mitig...
2016-12-01
magnitude of individual programs, all agencies agree funding shortfalls have a constraining effect on their AD programs. For example, a number of...Process ................................................................................................................................... 4 Funding ...process, funding , and preparing for electronic‐born records that will inundate the review process in the future.3
Future Directions: A Call for Actions
ERIC Educational Resources Information Center
Meyer, Richard
2011-01-01
The first part of this article is a discussion of the present contexts in which middle level teachers, students, and researchers learn and teach; it's a rather dismal portrait constrained by legislation and policies. The second part, in which hope begins to present itself, introduces readers to some middle level students, their teacher, and a…
Assessing Collaborative Learning: Big Data, Analytics and University Futures
ERIC Educational Resources Information Center
Williams, Peter
2017-01-01
Assessment in higher education has focused on the performance of individual students. This focus has been a practical as well as an epistemic one: methods of assessment are constrained by the technology of the day, and in the past they required the completion by individuals under controlled conditions of set-piece academic exercises. Recent…
Canadian Adolescents' Concerns in the Nuclear Age: Implications for Counsellors and Teachers.
ERIC Educational Resources Information Center
Harvey, C. Brian; And Others
1985-01-01
Presents data from questionnaires and interviews with adolescents regarding their concerns about living in the Nuclear Age. Results suggest that the nuclear threat further constrains planning for the future. Suggests implications for educators, who do not appear to serve major roles as socializing or communicating agents on this issue. (BH)
Investigating the Mechanisms of Learning from a Constrained Preparation for Future Learning Activity
ERIC Educational Resources Information Center
Siler, Stephanie A.; Klahr, David; Price, Norman
2013-01-01
Many studies have shown benefits associated with engaging students in problem-solving activities prior to administering lessons. These problem-solving activities are assumed to activate relevant knowledge and allow students to develop some initial knowledge structures, which support understanding of the lesson. In this paper we report the results…
Constrained range expansion and climate change assessments
Yohay Carmel; Curtis H. Flather
2006-01-01
Modeling the future distribution of keystone species has proved to be an important approach to assessing the potential ecological consequences of climate change (Loehle and LeBlanc 1996; Hansen et al. 2001). Predictions of range shifts are typically based on empirical models derived from simple correlative relationships between climatic characteristics of occupied and...
Beyond Test Prep: Moving the Mission Statement into the Classroom
ERIC Educational Resources Information Center
Jones, Emily
2010-01-01
A random walk through the mission statements of independent schools shows an admirable determination to educate students for an unknowable future, for creativity and problem solving, for responsible citizenship, for resiliency. Nevertheless, many of these same schools are constrained to work towards their mission-central goals in time stolen from…
Probing primordial features with future galaxy surveys
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ballardini, M.; Fedeli, C.; Moscardini, L.
2016-10-01
We study the capability of future measurements of the galaxy clustering power spectrum to probe departures from a power-law spectrum for primordial fluctuations. On considering the information from the galaxy clustering power spectrum up to quasi-linear scales, i.e. k < 0.1 h Mpc{sup −1}, we present forecasts for DESI, Euclid and SPHEREx in combination with CMB measurements. As examples of departures in the primordial power spectrum from a simple power-law, we consider four Planck 2015 best-fits motivated by inflationary models with different breaking of the slow-roll approximation. At present, these four representative models provide an improved fit to CMB temperaturemore » anisotropies, although not at statistical significant level. As for other extensions in the matter content of the simplest ΛCDM model, the complementarity of the information in the resulting matter power spectrum expected from these galaxy surveys and in the primordial power spectrum from CMB anisotropies can be effective in constraining cosmological models. We find that the three galaxy surveys can add significant information to CMB to better constrain the extra parameters of the four models considered.« less
Validity of Sudden Gains in Acute Phase Treatment of Depression
ERIC Educational Resources Information Center
Vittengl, Jeffrey R.; Clark, Lee Anna; Jarrett, Robin B.
2005-01-01
The authors examined the validity of sudden gains identified with T. Z. Tang and R. J. DeRubeis's (1999) method in 2 clinical data sets that involved treatment of major depressive disorder (N=227). Sudden gains replicated among self- and clinician reports of depressive symptoms and predicted better psychosocial functioning at the acute phase…
ERIC Educational Resources Information Center
Tang, Tony Z.; DeRubeis, Robert J.; Beberman, Rachel; Pham, Thu
2005-01-01
Using an independent cognitive-behavioral therapy (CBT) data set, the authors replicated T. Z. Tang and R. J. DeRubeis' (1999) discovery of sudden gains--sudden and large decreases in depression severity in a single between-session interval. By incorporating therapy session transcripts, the authors of this study improved the reliability of the…
Sudden Gains during Psychological Treatments of Anxiety and Depression: A Meta-Analysis
ERIC Educational Resources Information Center
Aderka, Idan M.; Nickerson, Angela; Boe, Hans Jakob; Hofmann, Stefan G.
2012-01-01
Objective: The present study quantitatively reviewed the literature on sudden gains in psychological treatments for anxiety and depression. The authors examined the short- and long-term effects of sudden gains on treatment outcome as well as moderators of these effects. Method: The authors conducted a literature search using PubMed, PsycINFO, the…
NASA Astrophysics Data System (ADS)
Kalscheuer, Thomas; Yan, Ping; Hedin, Peter; Garcia Juanatey, Maria d. l. A.
2017-04-01
We introduce a new constrained 2D magnetotelluric (MT) inversion scheme, in which the local weights of the regularization operator with smoothness constraints are based directly on the envelope attribute of a reflection seismic image. The weights resemble those of a previously published seismic modification of the minimum gradient support method introducing a global stabilization parameter. We measure the directional gradients of the seismic envelope to modify the horizontal and vertical smoothness constraints separately. An appropriate choice of the new stabilization parameter is based on a simple trial-and-error procedure. Our proposed constrained inversion scheme was easily implemented in an existing Gauss-Newton inversion package. From a theoretical perspective, we compare our new constrained inversion to similar constrained inversion methods, which are based on image theory and seismic attributes. Successful application of the proposed inversion scheme to the MT field data of the Collisional Orogeny in the Scandinavian Caledonides (COSC) project using constraints from the envelope attribute of the COSC reflection seismic profile (CSP) helped to reduce the uncertainty of the interpretation of the main décollement. Thus, the new model gave support to the proposed location of a future borehole COSC-2 which is supposed to penetrate the main décollement and the underlying Precambrian basement.
Parekh, Rulan S; Meoni, Lucy A; Jaar, Bernard G; Sozio, Stephen M; Shafi, Tariq; Tomaselli, Gordon F; Lima, Joao A; Tereshchenko, Larisa G; Estrella, Michelle M; Kao, W H Linda
2015-04-24
Sudden cardiac death occurs commonly in the end-stage renal disease population receiving dialysis, with 25% dying of sudden cardiac death over 5 years. Despite this high risk, surprisingly few prospective studies have studied clinical- and dialysis-related risk factors for sudden cardiac death and arrhythmic precursors of sudden cardiac death in end-stage renal disease. We present a brief summary of the risk factors for arrhythmias and sudden cardiac death in persons with end-stage renal disease as the rationale for the Predictors of Arrhythmic and Cardiovascular Risk in End Stage Renal Disease (PACE) study, a prospective cohort study of patients recently initiated on chronic hemodialysis, with the overall goal to understand arrhythmic and sudden cardiac death risk. Participants were screened for eligibility and excluded if they already had a pacemaker or an automatic implantable cardioverter defibrillator. We describe the study aims, design, and data collection of 574 incident hemodialysis participants from the Baltimore region in Maryland, U.S.A.. Participants were recruited from 27 hemodialysis units and underwent detailed clinical, dialysis and cardiovascular evaluation at baseline and follow-up. Cardiovascular phenotyping was conducted on nondialysis days with signal averaged electrocardiogram, echocardiogram, pulse wave velocity, ankle, brachial index, and cardiac computed tomography and angiography conducted at baseline. Participants were followed annually with study visits including electrocardiogram, pulse wave velocity, and ankle brachial index up to 4 years. A biorepository of serum, plasma, DNA, RNA, and nails were collected to study genetic and serologic factors associated with disease. Studies of modifiable risk factors for sudden cardiac death will help set the stage for clinical trials to test therapies to prevent sudden cardiac death in this high-risk population.
Varvarigou, Vasileia; Farioli, Andrea; Korre, Maria; Sato, Sho; Dahabreh, Issa J
2014-01-01
Objective To assess the association between risk of sudden cardiac death and stressful law enforcement duties compared with routine/non-emergency duties. Design Case distribution study (case series with survey information on referent exposures). Setting United States law enforcement. Participants 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. Main outcome measures 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. Results 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. Conclusions 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. PMID:25406189
Next of kin’s experiences of sudden and unexpected death from stroke - a study of narratives
2013-01-01
Background Death always evokes feelings in those close to the afflicted person. When death comes suddenly the time for preparation is minimal and the next of kin have to cope with the situation despite their own sorrow. The suddenness is found to be stressful for the next of kin and communication both with healthcare professionals and information about what has happened has been found helpful. The aim of this study was to illuminate the experiences of next of kin from the sudden and unexpected death of a relative from acute stroke. Methods Data was collected over a 12-month period in 2009–2010. Twelve next of kin of patients cared for in stroke units who died suddenly and unexpectedly from stroke were interviewed using a narrative method. The narratives were analyzed using narrative thematic analysis. Results Three themes emerged showing facets of next of kin’s experiences of a relative’s sudden and unexpected death from stroke: Divided feelings about the sudden and unexpected death; Perception of time and directed attention when keeping vigil; Contradictions and arbitrary memories when searching for understanding. Conclusions To have to live in the aftermath of severe stroke is absolute horror in people’s imagination and death is seen as the lesser of two evils. The sudden and unexpected death totally pervades the next of kin’s life, directs their attention to the dying person and even causes them to forget themselves and their own needs, and leads to difficulties in information intake. It is a challenge for the healthcare professionals to be able to identify the individual needs of the next of kin in this situation. PMID:23590246
Reduced risk of sudden death from chest wall blows (commotio cordis) with safety baseballs.
Link, Mark S; Maron, Barry J; Wang, Paul J; Pandian, Natesa G; VanderBrink, Brian A; Estes, N A Mark
2002-05-01
In an experimental model of sudden death from baseball chest wall impact (commotio cordis), we sought to determine if sudden death by baseball impact could be reduced with safety baseballs. Sudden cardiac death can occur after chest wall impact with a baseball (commotio cordis). Whether softer-than-standard (safety) baseballs reduce the risk of sudden death is unresolved from the available human data. In a juvenile swine model, ventricular fibrillation (VF) has been shown to be induced reproducibly by precordial impact with a 30-mph baseball 10 to 30 ms before the T-wave peak, and this likelihood was reduced with the softest safety baseballs (T-balls). To further test whether safety baseballs would reduce the risk of sudden death at velocities more relevant to youth sports competition, we used our swine model of commotio cordis to test baseballs propelled at the 40-mph velocity commonly attained in that sport. Forty animals received up to 3 chest wall impacts at 40 mph during the vulnerable period of repolarization for VF with 1 of 3 different safety baseballs of varying hardness, and also by a standard baseball. Safety baseballs propelled at 40 mph significantly reduced the risk for VF. The softest safety baseballs triggered VF in only 11% of impacts, compared with 19% and 22% with safety baseballs of intermediate hardness, and 69% with standard baseballs. In this experimental model of low-energy chest wall impact, safety baseballs reduced (but did not abolish) the risk of sudden cardiac death. More universal use of these safety baseballs may decrease the risk of sudden death on the playing field for young athletes.
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.
Acute otitis media associated bilateral sudden hearing loss: case report and literature review.
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.
Recent advances in understanding and prevention of sudden cardiac death
Vandenberg, Jamie I.; Perry, Matthew D.; Hill, Adam P.
2017-01-01
There have been tremendous advances in the diagnosis and treatment of heart disease over the last 50 years. Nevertheless, it remains the number one cause of death. About half of heart-related deaths occur suddenly, and in about half of these cases the person was unaware that they had underlying heart disease. Genetic heart disease accounts for only approximately 2% of sudden cardiac deaths, but as it typically occurs in younger people it has been a particular focus of activity in our quest to not only understand the underlying mechanisms of cardiac arrhythmogenesis but also develop better strategies for earlier detection and prevention. In this brief review, we will highlight trends in the recent literature focused on sudden cardiac death in genetic heart diseases and how these studies are contributing to a broader understanding of sudden death in the community. PMID:29026525
Stimulants and sudden death: what is a physician to do?
Wilens, Timothy E; Prince, Jefferson B; Spencer, Thomas J; Biederman, Joseph
2006-09-01
Recently, a US Food and Drug Administration advisory committee raised concerns about cardiovascular risks and sudden death in children and adolescents with attention-deficit/hyperactivity disorder who are receiving stimulants. We comment on the risk of sudden death in children/adolescents taking stimulants compared with population rates, biological plausibility, and known cardiovascular effects of stimulants to determine specific risk. There does not seem to be higher risk of sudden death in stimulant-treated individuals compared with the general population. Although there is evidence of biological plausibility, the known effects of the stimulants on cardiovascular electrophysiology and vital signs seem to be benign. There does not seem to be compelling findings of a medication-specific risk necessitating changes in our stimulant treatment of children and adolescents with attention-deficit/hyperactivity disorder. The use of existing guidelines on the use of stimulants (and psychotropic agents) may identify children, adolescents, and adults who are vulnerable to sudden death.
Sudden unexpected death from oligodendroglioma: a case report and review of the literature.
Manousaki, Maria; Papadaki, Helen; Papavdi, Asteria; Kranioti, Elena F; Mylonakis, Panagiotis; Varakis, John; Michalodimitrakis, Manolis
2011-12-01
Sudden and unexpected deaths due to asymptomatic 5 primary brain tumors are extremely rare, with an incidence that ranges from 0.16 to 3.2%. Usually, such tumors are glioblastomas or, less commonly, astrocytomas. Asymptomatic oligodendrogliomas causing sudden death are hardly ever reported among medico-legal investigated cases.We report a rare case of sudden and unexpected death from a previously asymptomatic and undiagnosed, well-differentiated, grade II oligodendrogloioma (WHO classification). According to the autopsy and the microscopic findings brain edema as a result of obstruction of the cerebrospinal fluid flow due to hemorrhagic leakage of the oligodendroglioma is incriminated as the most probable physiopathological mechanism for the sudden death. Diagnosis is mainly based on the special microscopic features of the tumor cells (typical "fried-egg" appearance), interrupted by a dense network of branching capillaries. We discuss further the pathophysiological mechanisms of death and present a short review of literature.
Harp, Dylan R.; Atchley, Adam L.; Painter, Scott L.; ...
2016-02-11
Here, the effect of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The Null-Space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21more » $$^{st}$$ century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows for the evaluation of intra-annual uncertainty due to soil properties and the inter-annual variability due to year to year differences in CESM climate forcings. After calibrating to borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant intra-annual uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Intra-annual uncertainties in projected soil moisture content and Stefan number are small. A volume and time integrated Stefan number decreases significantly in the future climate, indicating that latent heat of phase change becomes more important than heat conduction in future climates. Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. By comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we show that the effect of calibration-constrained uncertainty in soil properties, although significant, is less than that produced by structural climate model uncertainty for this location.« less
Harp, D. R.; Atchley, A. L.; Painter, S. L.; ...
2015-06-29
The effect of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The Null-Space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21st century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows formore » the evaluation of intra-annual uncertainty due to soil properties and the inter-annual variability due to year to year differences in CESM climate forcings. After calibrating to borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant intra-annual uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Intra-annual uncertainties in projected soil moisture content and Stefan number are small. A volume and time integrated Stefan number decreases significantly in the future climate, indicating that latent heat of phase change becomes more important than heat conduction in future climates. Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. As a result, by comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we show that the effect of calibration-constrained uncertainty in soil properties, although significant, is less than that produced by structural climate model uncertainty for this location.« less
NASA Astrophysics Data System (ADS)
Harp, D. R.; Atchley, A. L.; Painter, S. L.; Coon, E. T.; Wilson, C. J.; Romanovsky, V. E.; Rowland, J. C.
2015-06-01
The effect of soil property uncertainties on permafrost thaw projections are studied using a three-phase subsurface thermal hydrology model and calibration-constrained uncertainty analysis. The Null-Space Monte Carlo method is used to identify soil hydrothermal parameter combinations that are consistent with borehole temperature measurements at the study site, the Barrow Environmental Observatory. Each parameter combination is then used in a forward projection of permafrost conditions for the 21st century (from calendar year 2006 to 2100) using atmospheric forcings from the Community Earth System Model (CESM) in the Representative Concentration Pathway (RCP) 8.5 greenhouse gas concentration trajectory. A 100-year projection allows for the evaluation of intra-annual uncertainty due to soil properties and the inter-annual variability due to year to year differences in CESM climate forcings. After calibrating to borehole temperature data at this well-characterized site, soil property uncertainties are still significant and result in significant intra-annual uncertainties in projected active layer thickness and annual thaw depth-duration even with a specified future climate. Intra-annual uncertainties in projected soil moisture content and Stefan number are small. A volume and time integrated Stefan number decreases significantly in the future climate, indicating that latent heat of phase change becomes more important than heat conduction in future climates. Out of 10 soil parameters, ALT, annual thaw depth-duration, and Stefan number are highly dependent on mineral soil porosity, while annual mean liquid saturation of the active layer is highly dependent on the mineral soil residual saturation and moderately dependent on peat residual saturation. By comparing the ensemble statistics to the spread of projected permafrost metrics using different climate models, we show that the effect of calibration-constrained uncertainty in soil properties, although significant, is less than that produced by structural climate model uncertainty for this location.
The OakMapper WebGIS: improved access to sudden oak death spatial data
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...
[Sport's related sudden death].
Carré, François
2014-01-01
Non-traumatic sudden death related to sport is a rare but always dramatic event. Its causes are mainly cardiovascular. Prevention of sudden death depends on effective medical examination involving history, physical examination and resting ECG, as education of athletes who must follow the rules for safe sport practice and lastly training for emergency actions of the population. Copyright © 2014. Published by Elsevier Masson SAS.
Sudden Gains in Cognitive Therapy for Depression: A Replication and Extension
ERIC Educational Resources Information Center
Hardy, Gillian E.; Cahill, Jane; Stiles, William B.; Ispan, Caroline; Macaskill, Norman; Barkham, Michael
2005-01-01
Of 76 clients receiving 8-20 sessions of cognitive therapy (CT) in a joint university and a national health service clinic, 31 experienced sudden gains that appeared very similar to those first reported in clinical trials of CT by T. Z. Tang and R. J. DeRubeis (1999) and subsequently replicated in other studies. The sudden gains appeared less…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-01
... result in sudden fracture and failure of the fuselage skin panels, and consequent rapid decompression of..., which could result in sudden fracture and failure of the fuselage skin panels, and consequent rapid... fuselage skin panels at the chem-milled steps, which could result in sudden fracture and failure of the...
Welcome to the sudden oak death third science symposium
Susan J. Frankel
2008-01-01
On behalf of the United States Department of Agriculture (USDA)-Forest Service, Pacific Southwest Research Station and the California Oak Mortality Task Force, it is my pleasure to welcome you to the Sudden Oak Death Third Science Symposium. Looking back at the first sudden oak death science symposium held in Monterey in December 2002, it is amazing to see how far we...
Brugada Syndrome in a Patient with Vascular Ehlers-Danlos Syndrome: Sudden Death Risk Amplified.
D'Souza, Jason; Malhotra, Divyanshu; Goud, Aditya; Dahagam, Chanukya; Everett, George
2017-04-19
The vast majority of sudden cardiac arrests occur in patients with structural heart disease and in approximately 10% of the cases, it can occur in those with structurally normal hearts. Brugada syndrome is an autosomal dominant sodium channelopathy that has been implicated in sudden deaths. Given their low prevalence, our knowledge about Brugada syndrome is still evolving. Apart from schizophrenia, there have been no reports of associated medical conditions. We recently encountered a patient with vascular Ehlers-Danlos syndrome who was also found to have Brugada syndrome. Both these conditions share some common clinical presentations including a propensity for sudden death.
Sudden infant death syndrome caused by poliomyelitis.
Dunne, J W; Harper, C G; Hilton, J M
1984-07-01
Most seemingly well infants who die suddenly and unexpectedly have no adequate cause of death found on thorough postmortem examination. Respiratory and enteric viruses are often present, especially in the upper respiratory tract, but the infective process seems, of itself, insufficient to cause death. In the remainder of the cases, a variety of lesions will be discovered, including viral myocarditis, bronchiolitis, and sepsis. We report a case of sudden and unexpected death in a 5-week-old male infant due to acute anterior poliomyelitis. This case illustrates the importance of a thorough postmortem examination, including histologic studies of the brain stem and spinal cord in cases of sudden infant death syndrome.
Enhanced seasonal forecast skill following stratospheric sudden warmings
NASA Astrophysics Data System (ADS)
Sigmond, M.; Scinocca, J. F.; Kharin, V. V.; Shepherd, T. G.
2013-02-01
Advances in seasonal forecasting have brought widespread socio-economic benefits. However, seasonal forecast skill in the extratropics is relatively modest, prompting the seasonal forecasting community to search for additional sources of predictability. For over a decade it has been suggested that knowledge of the state of the stratosphere can act as a source of enhanced seasonal predictability; long-lived circulation anomalies in the lower stratosphere that follow stratospheric sudden warmings are associated with circulation anomalies in the troposphere that can last up to two months. Here, we show by performing retrospective ensemble model forecasts that such enhanced predictability can be realized in a dynamical seasonal forecast system with a good representation of the stratosphere. When initialized at the onset date of stratospheric sudden warmings, the model forecasts faithfully reproduce the observed mean tropospheric conditions in the months following the stratospheric sudden warmings. Compared with an equivalent set of forecasts that are not initialized during stratospheric sudden warmings, we document enhanced forecast skill for atmospheric circulation patterns, surface temperatures over northern Russia and eastern Canada and North Atlantic precipitation. We suggest that seasonal forecast systems initialized during stratospheric sudden warmings are likely to yield significantly greater forecast skill in some regions.
Postmortem ICD interrogation in mode of death classification.
Nikolaidou, Theodora; Johnson, Miriam J; Ghosh, Justin M; Marincowitz, Carl; Shah, Saumil; Lammiman, Michael J; Schilling, Richard J; Clark, Andrew L
2018-04-01
The definition of sudden death due to arrhythmia relies on the time interval between onset of symptoms and death. However, not all sudden deaths are due to arrhythmia. In patients with an implantable cardioverter defibrillator (ICD), postmortem device interrogation may help better distinguish the mode of death compared to a time-based definition alone. This study aims to assess the proportion of "sudden" cardiac deaths in patients with an ICD that have confirmed arrhythmia. We conducted a literature search for studies using postmortem ICD interrogation and a time-based classification of the mode of death. A modified QUADAS-2 checklist was used to assess risk of bias in individual studies. Outcome data were pooled where sufficient data were available. Our search identified 22 studies undertaken between 1982 and 2015 with 23,600 participants. The pooled results (excluding studies with high risk of bias) suggest that ventricular arrhythmias are present at the time of death in 76% of "sudden" deaths (95% confidence interval [CI] 67-85; range 42-88). Postmortem ICD interrogation identifies 24% of "sudden" deaths to be nonarrhythmic. Postmortem device interrogation should be considered in all cases of unexplained sudden cardiac death. © 2018 Wiley Periodicals, Inc.
Observational constraints on finite scale factor singularities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Denkiewicz, Tomasz, E-mail: atomekd@wmf.univ.szczecin.pl
2012-07-01
We discuss the combined constraints on a Finite Scale Factor Singularity (FSF) universe evolution scenario, which come from the shift parameter R, baryon acoustic oscillations (BAO) A, and from the type Ia supernovae. We show that observations allow existence of such singularities in the 2 × 10{sup 9} years in future (at 1σ CL) which is much farther than a Sudden Future Singularity (SFS), and that at the present moment of the cosmic evolution, one cannot differentiate between cosmological scenario which allow finite scale factor singularities and the standard ΛCDM dark energy models. We also show that there is anmore » allowed value of m = 2/3 within 1σ CL, which corresponds to a dust-filled Einstein-de-Sitter universe limit of the early time evolution and so it is pasted into a standard early-time scenario.« less
Climate change alters diffusion of forest pest: A model study
NASA Astrophysics Data System (ADS)
Jo, Woo Seong; Kim, Hwang-Yong; Kim, Beom Jun
2017-01-01
Population dynamics with spatial information is applied to understand the spread of pests. We introduce a model describing how pests spread in discrete space. The number of pest descendants at each site is controlled by local information such as temperature, precipitation, and the density of pine trees. Our simulation leads to a pest spreading pattern comparable to the real data for pine needle gall midge in the past. We also simulate the model in two different climate conditions based on two different representative concentration pathways scenarios for the future. We observe that after an initial stage of a slow spread of pests, a sudden change in the spreading speed occurs, which is soon followed by a large-scale outbreak. We found that a future climate change causes the outbreak point to occur earlier and that the detailed spatio-temporal pattern of the spread depends on the source position from which the initial pest infection starts.
Washington Geothermal Play Fairway Analysis Data From Potential Field Studies
Anderson, Megan; Ritzinger, Brent; Glen, Jonathan; Schermerhorn, William
2017-12-20
A recent study which adapts play fairway analysis (PFA) methodology to assess geothermal potential was conducted at three locations (Mount Baker, Mount St. Helens seismic zone, and Wind River valley) along the Washington Cascade Range (Forson et al. 2017). Potential field (gravity and magnetic) methods which can detect subsurface contrasts in physical properties, provides a means for mapping and modeling subsurface geology and structure. As part of the WA-Cascade PFA project, we performed potential field studies by collecting high-resolution gravity and ground-magnetic data, and rock property measurements to (1) identify and constrain fault geometries (2) constrain subsurface lithologic distribution (3) study fault interactions (4) identify areas favorable to hydrothermal flow, and ultimately (5) guide future geothermal exploration at each location.
Kin competition and the evolution of cooperation
Platt, Thomas G.; Bever, James D.
2017-01-01
Kin and multilevel selection theories predict that genetic structure is required for the evolution of cooperation. However, local competition among relatives can limit cooperative benefits, antagonizing the evolution of cooperation. We show that several ecological factors determine the extent to which kin competition constrains cooperative benefits. In addition, we argue that cooperative acts that expand local carrying capacity are less constrained by kin competition than other cooperative traits, and are therefore more likely to evolve. These arguments are particularly relevant to microbial cooperation, which often involves the production of public goods that promote population expansion. The challenge now is to understand how an organism’s ecology influences how much cooperative groups contribute to future generations and thereby the evolution of cooperation. PMID:19409651
Constraining Initiation and Onset Time of Plate Tectonics on Earth
NASA Astrophysics Data System (ADS)
Roller, G.
2014-12-01
The onset time for modern-style plate tectonics is still heavily debated among geoscientists. Proposed timings range from the Phanerozoic to the Hadean. Here I present a new theoretical approach to tackle this question. I combine ideas of nuclear astrophysics and geochronology and apply the concept of sudden nucleosynthesis to calculate so-called nucleogeochronometric Rhenium-Osmium model ages. Sudden nucleosynthesis has been suggested by nuclear theory [1-2] as a possible mechanism for the creation of the heavy isotopes. Hence, this concept may generally be used to identify rapid (r-) neutron-capture process events. For Earth, nucleogeochronometric model age calculations based upon published pyroxenite and komatiite data [3-5] point to an r-process event around 3 Ga. Since the r-process requires high neutron densities and temperatures within seconds, a gravitational core collapse forming at least a part of the inner core is discussed as a possible cause, thus initiating modern-style plate tectonics at that time. This age is in line with an earlier proposed value of 2.7 Ga for an inner core forming event [6], pronounced changes in the magnitude of the geomagnetic field and geological evidence like the onset of extensive plutonism and crust formation starting around the Archean-Proterozoic transition. Besides, results from nucleogeochronometric age calculations for published peridotitic pentlandites [7] lead to corrections as to their previously inconsistent model ages: These are now in good agreement with their Proterozoic 1.43 Ga isochronous regression line, supporting the model. [1] Burbidge et al. (1957) Revs. Mod. Phys. 29, 547 - 650. [2] Hoyle et al. (1960) ApJ 132, 565 - 590. [3] Reisberg et al. (1991) Earth Planet. Sci. Lett. 105, 196 - 213. [4] Roy-Barman et al. (1996) Chem. Geol. 130, 55 - 64. [5] Luck et al. (1984) Earth Planet Sci. Lett. 68, 205 - 208. [6] Hale (1987) Nature 329, 233 -237. [7] Smit et al. (2010) Geochim. Cosmochim. Acta 74, 3292 - 3306.
Detection of a sudden change of the field time series based on the Lorenz system
Li, Fang; Shen, BingLu; Yan, PengCheng; Song, Jian; Ma, DeShan
2017-01-01
We conducted an exploratory study of the detection of a sudden change of the field time series based on the numerical solution of the Lorenz system. First, the time when the Lorenz path jumped between the regions on the left and right of the equilibrium point of the Lorenz system was quantitatively marked and the sudden change time of the Lorenz system was obtained. Second, the numerical solution of the Lorenz system was regarded as a vector; thus, this solution could be considered as a vector time series. We transformed the vector time series into a time series using the vector inner product, considering the geometric and topological features of the Lorenz system path. Third, the sudden change of the resulting time series was detected using the sliding t-test method. Comparing the test results with the quantitatively marked time indicated that the method could detect every sudden change of the Lorenz path, thus the method is effective. Finally, we used the method to detect the sudden change of the pressure field time series and temperature field time series, and obtained good results for both series, which indicates that the method can apply to high-dimension vector time series. Mathematically, there is no essential difference between the field time series and vector time series; thus, we provide a new method for the detection of the sudden change of the field time series. PMID:28141832
Koo, Malcolm; Chen, Jin-Cherng; Hwang, Juen-Haur
2016-01-01
Cochleovestibular symptoms, such as vertigo, tinnitus, and sudden deafness, are common manifestations of microvascular diseases. However, it is unclear whether these symptoms occurred preceding the diagnosis of peripheral artery occlusive disease (PAOD). Therefore, the aim of this case-control study was to investigate the risk of PAOD among patients with vertigo, tinnitus, and sudden deafness using a nationwide, population-based health claim database in Taiwan. We identified 5,340 adult patients with PAOD diagnosed between January 1, 2006 and December 31, 2010 and 16,020 controls, frequency matched on age interval, sex, and year of index date, from the Taiwan National Health Insurance Research Database. Risks of PAOD in patients with vertigo, tinnitus, or sudden deafness were separately evaluated with multivariate logistic regression analyses. Of the 5,340 patients with PAOD, 12.7%, 6.7%, and 0.3% were diagnosed with vertigo, tinnitus, and sudden deafness, respectively. In the controls, 10.6%, 6.1%, and 0.3% were diagnosed with vertigo (P < 0.001), tinnitus (P = 0.161), and sudden deafness (P = 0.774), respectively. Results from the multivariate logistic regression analyses showed that the risk of PAOD was significantly increased in patients with vertigo (adjusted odds ratio = 1.12, P = 0.027) but not in those with tinnitus or sudden deafness. A modest increase in the risk of PAOD was observed among Taiwanese patients with vertigo, after adjustment for comorbidities.
Nadir Erbilgin; Brice A. McPherson; Pierluigi Bonello; David L. Wood; Andrew J. Nelson
2008-01-01
Sudden oak death (SOD) has had devastating effects on several oak species in many California coastal forests. Phytophthora ramorum has been identified as the primary causal agent of sudden oak death. While the pathogen may be capable of killing mature trees, it is likely that in nature opportunistic organisms play significant roles in the decline and...
Sudden Oak Death, Phytophthora ramorum: A Persistent Threat to Oaks and Other Tree Species
S.J. Frankel; K.M. Palmieri
2014-01-01
This paper reviews the status and management of sudden oak death and âsudden larch deathâ in the urban and wildland forests of California, Oregon, and the UK. The causal pathogen, Phytophthora ramorum, was discovered in all three locations over a decade ago; however, efforts to contain and eliminate infestations have been unsuccessful. These less...
Fleming, P J; Gilbert, R; Azaz, Y; Berry, P J; Rudd, P T; Stewart, A; Hall, E
1990-01-01
OBJECTIVE--To determine the relation between sleeping position and quantity of bedding and the risk of sudden unexpected infant death. DESIGN--A study of all infants dying suddenly and unexpectedly and of two controls matched for age and date with each index case. The parents of control infants were interviewed within 72 hours of the index infant's death. Information was collected on bedding, sleeping position, heating, and recent signs of illness for index and control infants. SETTING--A defined geographical area comprising most of the county of Avon and part of Somerset. SUBJECTS--72 Infants who had died suddenly and unexpectedly (of whom 67 had died from the sudden infant death syndrome) and 144 control infants. RESULTS--Compared with the control infants the infants who had died from the sudden infant death syndrome were more likely to have been sleeping prone (relative risk 8.8; 95% confidence interval 7.0 to 11.0; p less than 0.001), to have been more heavily wrapped (relative risk 1.14 per tog above 8 tog; 1.03 to 1.28; p less than 0.05), and to have had the heating on all night (relative risk 2.7; 1.4 to 5.2; p less than 0.01). These differences were less pronounced in the younger infants (less than 70 days) than the older ones. The risk of sudden unexpected death among infants older than 70 days, nursed prone, and with clothing and bedding of total thermal resistance greater than 10 tog was increased by factors of 15.1 (2.6 to 89.6) and 25.2 (3.7 to 169.0) respectively compared with the risk in infants of the same age nursed supine or on their side and under less than 6 tog of bedding. CONCLUSIONS--Overheating and the prone position are independently associated with an increased risk of sudden unexpected infant death, particularly in infants aged more than 70 days. Educating parents about appropriate thermal care and sleeping position of infants may help to reduce the incidence of the sudden infant death syndrome. PMID:2390588
Universities Look to Obama to Expand Their Role in Development Abroad
ERIC Educational Resources Information Center
McMurtrie, Beth
2009-01-01
As the Obama administration takes office, educators involved in development work abroad look to the future with hope. Although the economic downturn may constrain the new president's ability to make financial commitments abroad, Barack Obama has said he wants to double the amount of foreign assistance provided by the United States to fight poverty…
A new algorithm for stand table projection models.
Quang V. Cao; V. Clark Baldwin
1999-01-01
The constrained least squares method is proposed as an algorithm for projecting stand tables through time. This method consists of three steps: (1) predict survival in each diameter class, (2) predict diameter growth, and (3) use the least squares approach to adjust the stand table to satisfy the constraints of future survival, average diameter, and stand basal area....
Jean Lienard; John Harrison; Nikolay Strigul
2015-01-01
Forested ecosystems are shaped by climate, soil and biotic interactions, resulting in constrained spatial distribution of species and biomes. Tolerance traits of species determine their fundamental ecological niche, while biotic interactions narrow tree distributions to the realized niche. In particular, shade, drought and waterlogging tolerances have been well-...
ERIC Educational Resources Information Center
Badger, Marcus P. S.; Pancost, Richard D.; Harrison, Timothy G.
2011-01-01
The reconstruction of ancient atmospheric carbon dioxide concentrations is essential to understanding the history of the Earth and life. It is also an important guide to identifying the sensitivity of the Earth system to this greenhouse gas and, therefore, constraining its future impact on climate. However, determining the concentration of…
2007-06-01
constrained list of command words could be valuable in many systems, as would the ability of driverless vehicles to navigate through a route...Sensemaking in UGVs • Future Combat Systems UGV roles – Driverless trucks – Robotic mules (soldier, squad aid) – Intelligent munitions – And more! • Some
Heather R. McCarthy; Ram Oren; Adrien C. Finzi; Kurt H. Johnsen
2006-01-01
Net primary productivity (NPP) is enhanced under future atmospheric [CO2] in temperate forests representing a broad range of productivity. Yet questions remain in regard to how elevated [CO2]-induced NPP enhancement may be affected by climatic variations and limiting nutrient resources, as well as how this additional...
How Might the Ares V Change the Need for Future Mirror Technology
NASA Technical Reports Server (NTRS)
Stahl, H. Philip
2008-01-01
More Massive Missions do not need to be More Expensive. Simple, robust, low-risk, high-TRL mission is likely to be low cost. It is also likely to be more massive than a complex, high-risk, low TRL mission. The challenge will be to overcome human nature. Launch Date Constrained Missions Cost Less
Sochan, Anne M
2011-07-01
How should nursing knowledge advance? This exploration contextualizes its evolution past and present. In addressing how it evolved in the past, a probable historical evolution of its development draws on the perspectives of Frank & Gills's World System Theory, Kuhn's treatise on Scientific Revolutions, and Foucault's notions of Discontinuities in scientific knowledge development. By describing plausible scenarios of how nursing knowledge evolved, I create a case for why nursing knowledge developers should adopt a post-structural stance in prioritizing their research agenda(s). Further, by adopting a post-structural stance, I create a case on how nurses can advance their disciplinary knowledge using an engaging post-colonial strategy. Given an interrupted history caused by influence(s) constraining nursing's knowledge development by power structures external, and internal, to nursing, knowledge development can evolve in the future by drawing on post-structural interpretation, and post-colonial strategy. The post-structural writings of Deleuze & Guattari's understanding of 'Nomadology' as a subtle means to resist being constrained by existing knowledge development structures, might be a useful stance to understanding the urgency of why nursing knowledge should advance addressing the structural influences on its development. Furthermore, Bhabha's post-colonial elucidation of 'Hybridity' as an equally discreet means to change the culture of those constraining structures is an appropriate strategy to enact how nursing knowledge developers can engage with existing power structures, and simultaneously influence that engagement. Taken together, 'post-structural stance' and 'post-colonial strategy' can refocus nursing scholarship to learn from its past, in order to develop relevant disciplinary knowledge in its future. © 2011 Blackwell Publishing Ltd.
Sudden Death: An Uncommon Occurrence in Dementia with Lewy Bodies.
Molenaar, Joery P; Wilbers, Joyce; Aerts, Marjolein B; Leijten, Quinten H; van Dijk, Jan G; Esselink, Rianne A; Bloem, Bastiaan R
2016-01-01
We present a 75-year-old woman with dementia and parkinsonism who developed severe orthostatic hypotension and eventually died. Autopsy revealed extensive Lewy body formation in the midbrain, limbic system, intermediate spinal cord, and medulla oblongata. Furthermore, a vast amount of Lewy bodies was seen in the paravertebral sympathetic ganglia which likely explained the severe autonomic failure. We speculate that this autonomic failure caused sudden death through dysregulation of respiration or heart rhythm, reminiscent of sudden death in multiple system atrophy (MSA). Clinicians should be aware of this complication in patients presenting with parkinsonism and autonomic dysfunction, and that sudden death may occur in dementia with Lewy bodies (DLB) as it does in MSA.
CKD and Sudden Cardiac Death: Epidemiology, Mechanisms, and Therapeutic Approaches
Whitman, Isaac R.; Feldman, Harold I.
2012-01-01
Multiple studies demonstrate a strong independent association between CKD and cardiovascular events including death, heart failure, and myocardial infarction. This review focuses on recent clinical studies that expand this spectrum of adverse cardiovascular events to include ventricular arrhythmias and sudden cardiac death. In addition, experimental models suggest structural remodeling of the heart and electrophysiologic changes in this population. These processes may explain the increased arrhythmic risk in kidney disease and aid in identifying patients who are at higher risk for sudden cardiac death. Finally, we review here the data to support the use of pharmacologic and device-based therapies for both the primary and secondary prevention of sudden cardiac death. PMID:23100219
[Three good reasons to perform a postmortem examination in all cases of juvenile sudden death].
d'Amati, Giulia; di Gioia, Cira R T; Silenzi, Paola F; Gallo, Pietro
2009-04-01
The aim of this review is to underline the reasons why a post-mortem examination has to be performed in all cases of juvenile sudden death. Sudden death in children and young adults can be caused by potentially heritable cardiovascular disorders and fatal outcome is often the first symptom in apparently healthy subjects. In these cases, a careful autopsy, performed according to a standardized protocol, becomes the sole diagnostic tool to guide clinical and molecular genetic family screening and to adopt the proper therapeutic and preventive strategies. Thus, a post-mortem examination is a fundamental part of a multidisciplinary approach to the issue of juvenile sudden death.
Pericardial Cyst: Cause of Sudden Cardiac Death?
Ley, Marie Brix; Larsen, Maiken Kudahl
2018-05-21
Cardiovascular disease is the leading cause of sudden death in the world. The etiology of sudden cardiac death involves a wide range of diseases, but seldom pericardial cysts. A pericardial cyst is an uncommon cyst usually located in the middle mediastinum and rarely in the posterior part. They are usually harmless and asymptomatic. Here, we present a case of a 63-year-old woman who presented with dyspnea and hoarseness, but died suddenly after a CT scan was attempted. The detailed forensic pathologic and histologic examination revealed a pericardial cyst located in the posterior mediastinum. Toxicology and biochemistry tests, including tryptase, found no competing cause of death. © 2018 American Academy of Forensic Sciences.
NASA Astrophysics Data System (ADS)
Havens, K. E.; Kane, A.
2016-02-01
In 2012 the oyster population in Apalachicola Bay, Florida suddenly collapsed. The catastrophic event, which had severe impacts on the local economy, coincided with two years of record low rainfall over the watershed and the lowest river flows into the estuary in 89 years. Elevated salinity in the bay allowed marine predators, parasites and pathogens from the Gulf of Mexico to increase in abundance and impact the oyster population. Population modeling indicated that the proximal cause of the collapse was high juvenille mortality. Ecosystem modeling (using ECOSPACE) indicated that because the system also had considerably degraded habitat, recovery of oyster harvest to pre-impact levels would require both (a) substantially reduced harvest pressure for a period of two years and (b) restoration of at least 1,000 acres of oyster reef. Given that in the future climate change may result both in greater saltwater inputs (due to sea level rise) and increased frequency and/or intensity of droughts, the effects observed in Apalachicola Bay can provide a 'lens' into the future in regard to estuarine impacts.
Biyikli, Emre; To, Albert C.
2015-01-01
A new topology optimization method called the Proportional Topology Optimization (PTO) is presented. As a non-sensitivity method, PTO is simple to understand, easy to implement, and is also efficient and accurate at the same time. It is implemented into two MATLAB programs to solve the stress constrained and minimum compliance problems. Descriptions of the algorithm and computer programs are provided in detail. The method is applied to solve three numerical examples for both types of problems. The method shows comparable efficiency and accuracy with an existing optimality criteria method which computes sensitivities. Also, the PTO stress constrained algorithm and minimum compliance algorithm are compared by feeding output from one algorithm to the other in an alternative manner, where the former yields lower maximum stress and volume fraction but higher compliance compared to the latter. Advantages and disadvantages of the proposed method and future works are discussed. The computer programs are self-contained and publicly shared in the website www.ptomethod.org. PMID:26678849
Dempers, Johan; Sens, Mary Ann; Wadee, Shabbir Ahmed; Kinney, Hannah C.; Odendaal, Hein J.; Wright, Colleen A.
2010-01-01
The classification of an unexpected infant death as the sudden infant death syndrome (SIDS) depends upon a complete autopsy and death scene investigation to exclude known causes of death. Here we report the death of a four-month-old infant in a tuberculosis endemic area that presented as a sudden unexpected death in infancy (SUDI) with no apparent explanation based on the death scene characteristics. The autopsy, however, revealed progressive primary pulmonary tuberculosis with intrathoracic adenopathy, compression of the tracheobronchial tree and miliary lesions in the liver. This case underscores the clinical difficulties in the diagnosis of infantile tuberculosis, as well as the possibility of sudden death as part of its protean manifestations. The pathology and clinical progression of tuberculosis in infants differs from older children and adults due to the immature immune response in infants. This case dramatically highlights the need for complete autopsies in all sudden and unexpected infant deaths, as well as the public health issues in a sentinel infant tuberculosis diagnosis. PMID:20705406
Laryngeal dystonia gravidarum: sudden onset of adductor spasmodic dysphonia in pregnancy.
Ankola, Ashish; Sulica, Lucian; Murry, Thomas
2013-12-01
The purpose of this study was to identify the presence or absence of known factors related to onset of adductor spasmodic dysphonia (ADSD) in a population with sudden onset during or after pregnancy. Retrospective review. A review of 350 patient records identified five patients with sudden onset of ADSD related to pregnancy. An age-matched group with sudden onset of ADSD not related to pregnancy served as controls. All subjects completed a 20-question survey of risk factors relevant to ADSD. The average age of onset in both groups was 31 years. Three had onset of ADSD in the postpartum period, the other two during pregnancy. Significantly increased avocational voice use was found in the pregnant group compared to the control group. There was a significant difference in the two groups regarding cumulative risk factors traditionally associated with ADSD. Sudden onset of ADSD can occur in pregnancy in women with clinical profiles that differ from traditional ADSD patients. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.
2017-01-27
jsc2017e011279 (01/27/2017) --- Crowds of visitors line up for the NASA Orion Journey to Mars ride at the Houston Texas NFL Live Super Bowl LI event on Discovery Green Jan. 27, 2017. With people safely seated and virtual googles in place the ride pulls the Orion capsule up 90 feet then drops them suddenly to the bottom providing a physical experience as well as a visual one while experiencing the trip to Mars and back. The virtual reality trip is a popular no cost feature as part of NASA’s Future Flight area which also houses many other NASA space exploration and science exhibits. NASA PHOTOGRAPHER: Robert Markowitz
Padeken, D; Sotiriou, D; Boddy, K; Gerzer, R
1995-02-01
Migration from space medicine toward telemedicine services is described by potential application areas in highly populated and remote areas of Europe. Special emphasis is laid upon links between mobile patient monitoring and health care in remote areas. Pilot projects are described for home (mobile) monitoring of newborn infants endangered by sudden infant death (SID) and adults suffering from sleep apnoea. Health care in remote areas is described by the "TeleClinic-project" which will link national nodes for telemedicine services in several European states for the mobile European citizen. Another project describes the future potential of robotics for semiautonomous ultrasound diagnostics and for realtime interaction of remote experts with diagnostics and therapy.
A Two Population Model for the Stock Market Problem
NASA Astrophysics Data System (ADS)
Skiadas, Christos H.
The development of the last year disaster in the Stock Markets all over the world gave rise to reconsidering the previous models used. It is clear that, even in an organized international or national context, large fluctuations and sudden losses may occur. This paper explores a two populations' model. The populations are conflicting into the same environment (a Stock Market) by following the main rules present, that is mutual interaction between adopters, potential adopters, word-of-mouth communication and of course by taking into consideration the innovation diffusion process. The proposed model has special futures expressed by third order terms providing characteristic stationary points.
Measuring System for Growth Control of the Spirulina Aquaculture
NASA Astrophysics Data System (ADS)
Ponce S., Claudio; Ponce L., Ernesto; Bernardo S., Barraza
2008-11-01
It describes the workings of a data-logging instrument that measures growth levels of the Spirulina aquaculture. The Spirulina is a very delicate algae and its culture may be suddenly lost due to overgrowth. This kind of instrument is not at present available in the market. The transduction is a submergible laser device whose measuring margin of error is near to 0.28%. The advantage of this new instrument is the improvement in the measurement and the low cost. The future application of this work is related to the industrial production of food and fuel from micro algae culture, for the growing world population.
Using the 12-Lead Electrocardiogram in the Care of Athletic Patients.
Yeo, Tee Joo; Sharma, Sanjay
2016-11-01
This article summarizes the role of the 12-lead electrocardiogram (ECG) for the clinical care of athletes, with particular reference to the influence of age, gender, ethnicity, and type of sport on the appearance of the ECG, and its role in differentiating physiologic exercise-related changes from pathologic conditions implicated in sudden cardiac death (SCD). The article also explores the potential role of the ECG in detecting athletes at risk of SCD. In addition, the article reviews the evolution of ECG interpretation criteria and emphasizes the limitations of the ECG as well as the potential for future research. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Chen, Zi-Yu; Chen, Shi; Dan, Jia-Kun; Li, Jian-Feng; Peng, Qi-Xian
2011-10-01
A simple one-dimensional analytical model for electromagnetic emission from an unmagnetized wakefield excited by an intense short-pulse laser in the nonlinear regime has been developed in this paper. The expressions for the spectral and angular distributions of the radiation have been derived. The model suggests that the origin of the radiation can be attributed to the violent sudden acceleration of plasma electrons experiencing the accelerating potential of the laser wakefield. The radiation process could help to provide a qualitative interpretation of existing experimental results, and offers useful information for future laser wakefield experiments.
ECPR for Refractory Out-Of-Hospital Cardiac Arrest
2018-05-09
Cardiac Arrest; Heart Arrest; Sudden Cardiac Arrest; Cardiopulmonary Arrest; Death, Sudden, Cardiac; Cardiopulmonary Resuscitation; CPR; Extracorporeal Cardiopulmonary Resuscitation; Extracorporeal Membrane Oxygenation
The Not-So-Sudden Results of the Sudden Saw Log Study - Growth and Yield Through Age 45
V. Clark Baldwin; Daniel J. Leduc; Robert B. Ferguson; James B. Baker; Rodney L. Busby
1998-01-01
The Sudden-Saw Log Study, located near Crossett, AR, was established to test the hypothesis that lobfolly pine plantations can produce sawtimber on good sites in 30 years. Study measurements reported at stand age 33 years show that the hypothesis is true. Fortunately, the study was not terminated at that time. Inventory data were also collected at stand ages 36, 39,...
The Molecular Autopsy: Should the Evaluation Continue After the Funeral?
Tester, David J.; Ackerman, Michael J.
2012-01-01
Sudden cardiac death (SCD) is one of the most common causes of death in developed countries, with most SCDs involving the elderly, and structural heart disease evident at autopsy. Each year, however, thousands of sudden deaths involving individuals younger than 35 years of age remain unexplained after a comprehensive medicolegal investigation that includes an autopsy. In fact, several epidemiologic studies have estimated that at least 3% and up to 53% of sudden deaths involving previously healthy children, adolescents, and young adults show no morphologic 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) yield no evidence to be found at autopsy, leaving coroners, medical examiners, and forensic pathologists only to 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 either a cardiologic and genetic evaluation of first- or second-degree relatives or a molecular autopsy may elucidate the underlying mechanism contributing to the sudden death and allow for identification of living family members with the pathogenic substrate that renders them vulnerable, with an increased risk for cardiac events including syncope, cardiac arrest, and sudden death. PMID:22307399
Tanaka, Shin-ichiro; Yasuda, Tomoyuki; Ishida, Tatsuro; Fujioka, Yoshio; Tsujino, Takeshi; Miki, Tetsuo; Hirata, Ken-ichi
2013-05-01
Lecithin:cholesterol acyltransferase (LCAT) is thought to be important in reverse cholesterol transport. However, its association with coronary heart disease (CHD) and sudden death is controversial. We prospectively studied 1927 individuals from the general population. Serum concentrations of apolipoprotein A-I, A-II, B, C-II, C-III, E, and LCAT activity measured as a serum cholesterol esterification rate were evaluated. We documented 61 events of CHD and sudden death during 10.9 years of follow-up. After adjustment for age and sex, LCAT activity was significantly associated with the risk of CHD and sudden death (hazard ratio, 3.02; 95% confidence interval, 1.49-6.12; P=0.002). In multivariate analysis adjusted for age, sex, current smoking status, history of diabetes mellitus, body mass index, systolic blood pressure, serum total cholesterol, and serum high-density lipoprotein cholesterol concentrations, the hazard ratio of LCAT activity for the risk of CHD and sudden death remained significant (hazard ratio, 3.07; 95% confidence interval, 1.35-7.01; P=0.008). However, when it was analyzed for men and women separately, this association remained significant only in women. Increased LCAT activity measured as a serum cholesterol esterification rate was a risk for CHD and sudden death in a Japanese general population.
Krexi, Dimitra; Sheppard, Mary N
2017-05-01
This study aims to determine the causes of sudden cardiac death during pregnancy and in the postpartum period and patients' characteristics. There are few studies in the literature. Eighty cases of sudden unexpected death due to cardiac causes in relation to pregnancy and postpartum period in a database of 4678 patients were found and examined macroscopically and microscopically. The mean age was 30±7 years with a range from 16 to 43 years. About 30% were 35 years old or older; 50% of deaths occurred during pregnancy and 50% during the postpartum period. About 59.18% were obese or overweight where body mass index data were available. The leading causes of death were sudden arrhythmic death syndrome (SADS) (53.75%) and cardiomyopathies (13.80%). Other causes include dissection of aorta or its branches (8.75%), congenital heart disease (2.50%) and valvular disease (3.75%). This study highlights sudden cardiac death in pregnancy or in the postpartum period, which is mainly due to SADS with underlying channelopathies and cardiomyopathy. We wish to raise awareness of these frequently under-recognised entities in maternal deaths and the need of cardiological screening of the family as a result of the diagnosis. Copyright © 2017 Elsevier B.V. All rights reserved.
Krexi, Dimitra; Sheppard, Mary N
2017-09-01
This study aims to determine the causes of sudden cardiac death during pregnancy and in the postpartum period and patients' characteristics. There are few studies in the literature. Eighty cases of sudden unexpected death due to cardiac causes in relation to pregnancy and postpartum period in a database of 4678 patients were found and examined macroscopically and microscopically. The mean age was 30±7years with a range from 16 to 43 years. About 30% were 35 years old or older; 50% of deaths occurred during pregnancy and 50% during the postpartum period. About 59.18% were obese or overweight where body mass index data were available. The leading causes of death were sudden arrhythmic death syndrome (SADS) (53.75%) and cardiomyopathies (13.80%). Other causes include dissection of aorta or its branches (8.75%), congenital heart disease (2.50%) and valvular disease (3.75%). This study highlights sudden cardiac death in pregnancy or in the postpartum period, which is mainly due to SADS with underlying channelopathies and cardiomyopathy. We wish to raise awareness of these frequently under-recognised entities in maternal deaths and the need of cardiological screening of the family as a result of the diagnosis. Copyright © 2017 Elsevier B.V. All rights reserved.
Turillazzi, Emanuela; Frati, Paola; Pascale, Natascha; Pomara, Cristoforo; Grilli, Giampaolo; Viola, Rocco Valerio; Fineschi, Vittorio
2016-01-01
Multi-phase post-mortem CT-angiography (MPMCTA) has the great potential to increase the quality of the post-mortem investigation, especially in the area of sudden death; however, its role as routine complement to the pathology toolbox is still questioned as it needs to be further standardized. The aim of this study is to investigate the contribution of MPMCTA in cases of sudden unexplained death in adults and in particular in sudden cardiovascular death. Sixty-eight sudden unexpected deaths of adults were investigated at our institution between 2012 and 2013. Ten cases underwent MPMCTA and autopsy and were included in the study. Before the angiographic step by complete filling of the vascular system, prior to any manipulation of the body, a non-contrast CT-scan was carried out. Image reconstructions were performed on a CT workstation (Vitrea) and two radiologists experienced with post mortem imaging interpreted the MPMCTA findings. In all 10 cases, we could state a good correlation between combination of post-mortem CT and MPMCTA and autopsy procedures, confirming a high diagnostic sensitivity. With this case series we want to illustrate the advantages offered by performing MPMCTA when facing a sudden death, regardless of specific suspicion for acute coronary syndrome or other vascular or ischemic disease. PMID:27928228
A Policy Impact Analysis of the Mandatory NCAA Sickle Cell Trait Screening Program
Tarini, Beth A; Brooks, Margaret Alison; Bundy, David G
2012-01-01
Objective To estimate the impact of the mandatory National Collegiate Athletic Association (NCAA) sickle cell trait (SCT) screening policy on the identification of sickle cell carriers and prevention of sudden death. Data Source We used NCAA reports, population-based SCT prevalence estimates, and published risks for exercise-related sudden death attributable to SCT. Study Design We estimated the number of sickle cell carriers identified and the number of potentially preventable sudden deaths with mandatory SCT screening of NCAA Division I athletes. We calculated the number of student-athletes with SCT using a conditional probability based upon SCT prevalence data and self-identified race/ethnicity status. We estimated sudden deaths over 10 years based on published attributable risk of exercise-related sudden death due to SCT. Principal Findings We estimate that over 2,000 NCAA Division I student-athletes with SCT will be identified under this screening policy and that, without intervention, about seven NCAA Division I student-athletes would die suddenly as a complication of SCT over a 10-year period. Conclusion Universal sickle cell screening of NCAA Division I student-athletes will identify a substantial number of sickle cell carriers. A successful intervention could prevent about seven deaths over a decade. PMID:22150647
Bilbily, John; McCollum, Betsy
2017-01-01
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. PMID:28396815
Radnic, Bojana; Radojevic, Nemanja; Vucinic, Jelena; Duborija-Kovacevic, Natasa
2017-07-01
Most young patients with mild-to-moderate aortic stenosis show no symptoms, and sudden death appears only occasionally. We hypothesised that malignant ventricular arrhythmias could be responsible for the high incidence of sudden death in such patients. If multiple factors such as asymptomatic aortic stenosis in association with arrhythmia-provoking agents are involved, could it be sufficient to account for sudden unexpected death? In this study, eight cases of sudden death in young adults, with ages ranging from 22 to 36 years, who had never reported any symptoms that could be related to aortic stenosis, were investigated. Full autopsies were performed, and congenital aortic stenosis in all eight cases was confirmed. DNA testing for channelopathies was negative. Comprehensive toxicological analyses found an electrolyte imbalance, or non-toxic concentrations of amitriptyline, terfenadine, caffeine, and ethanol. Collectively, these results suggest that congenital asymptomatic aortic stenosis without cardiac hypertrophy in young adults is not sufficient to cause sudden death merely on its own; rather, an additional provoking factor is necessary. According to our findings, the provoking factor may be a state of physical or emotional stress, a state of electrolyte imbalance, or even taking a therapeutic dose of a particular drug.
Potential asphyxia and brainstem abnormalities in sudden and unexpected death in infants.
Randall, Bradley B; Paterson, David S; Haas, Elisabeth A; Broadbelt, Kevin G; Duncan, Jhodie R; Mena, Othon J; Krous, Henry F; Trachtenberg, Felicia L; Kinney, Hannah C
2013-12-01
Sudden and unexplained death is a leading cause of infant mortality. Certain characteristics of the sleep environment increase the risk for sleep-related sudden and unexplained infant death. These characteristics have the potential to generate asphyxial conditions. We tested the hypothesis that infants may be exposed to differing degrees of asphyxia in sleep environments, such that vulnerable infants with a severe underlying brainstem deficiency in serotonergic, γ-aminobutyric acid-ergic, or 14-3-3 transduction proteins succumb even without asphyxial triggers (e.g., supine), whereas infants with intermediate or borderline brainstem deficiencies require asphyxial stressors to precipitate death. We classified cases of sudden infant death into categories relative to a "potential asphyxia" schema in a cohort autopsied at the San Diego County Medical Examiner's Office. Controls were infants who died with known causes of death established at autopsy. Analysis of covariance tested for differences between groups. Medullary neurochemical abnormalities were present in both infants dying suddenly in circumstances consistent with asphyxia and infants dying suddenly without obvious asphyxia-generating circumstances. There were no differences in the mean neurochemical measures between these 2 groups, although mean measures were both significantly lower (P < .05) than those of controls dying of known causes. We found no direct relationship between the presence of potentially asphyxia conditions in the sleep environment and brainstem abnormalities in infants dying suddenly and unexpectedly. Brainstem abnormalities were associated with both asphyxia-generating and non-asphyxia generating conditions. Heeding safe sleep messages is essential for all infants, especially given our current inability to detect underlying vulnerabilities.
Potential Asphyxia and Brainstem Abnormalities in Sudden and Unexpected Death in Infants
Randall, Bradley B.; Paterson, David S.; Haas, Elisabeth A.; Broadbelt, Kevin G.; Duncan, Jhodie R.; Mena, Othon J.; Krous, Henry F.; Trachtenberg, Felicia L.
2013-01-01
OBJECTIVE: Sudden and unexplained death is a leading cause of infant mortality. Certain characteristics of the sleep environment increase the risk for sleep-related sudden and unexplained infant death. These characteristics have the potential to generate asphyxial conditions. We tested the hypothesis that infants may be exposed to differing degrees of asphyxia in sleep environments, such that vulnerable infants with a severe underlying brainstem deficiency in serotonergic, γ-aminobutyric acid-ergic, or 14-3-3 transduction proteins succumb even without asphyxial triggers (eg, supine), whereas infants with intermediate or borderline brainstem deficiencies require asphyxial stressors to precipitate death. METHODS: We classified cases of sudden infant death into categories relative to a “potential asphyxia” schema in a cohort autopsied at the San Diego County Medical Examiner’s Office. Controls were infants who died with known causes of death established at autopsy. Analysis of covariance tested for differences between groups. RESULTS: Medullary neurochemical abnormalities were present in both infants dying suddenly in circumstances consistent with asphyxia and infants dying suddenly without obvious asphyxia-generating circumstances. There were no differences in the mean neurochemical measures between these 2 groups, although mean measures were both significantly lower (P < .05) than those of controls dying of known causes. CONCLUSIONS: We found no direct relationship between the presence of potentially asphyxia conditions in the sleep environment and brainstem abnormalities in infants dying suddenly and unexpectedly. Brainstem abnormalities were associated with both asphyxia-generating and non–asphyxia generating conditions. Heeding safe sleep messages is essential for all infants, especially given our current inability to detect underlying vulnerabilities. PMID:24218471
Hwang, Juen-Haur
2016-01-01
Background Cochleovestibular symptoms, such as vertigo, tinnitus, and sudden deafness, are common manifestations of microvascular diseases. However, it is unclear whether these symptoms occurred preceding the diagnosis of peripheral artery occlusive disease (PAOD). Therefore, the aim of this case-control study was to investigate the risk of PAOD among patients with vertigo, tinnitus, and sudden deafness using a nationwide, population-based health claim database in Taiwan. Methods We identified 5,340 adult patients with PAOD diagnosed between January 1, 2006 and December 31, 2010 and 16,020 controls, frequency matched on age interval, sex, and year of index date, from the Taiwan National Health Insurance Research Database. Risks of PAOD in patients with vertigo, tinnitus, or sudden deafness were separately evaluated with multivariate logistic regression analyses. Results Of the 5,340 patients with PAOD, 12.7%, 6.7%, and 0.3% were diagnosed with vertigo, tinnitus, and sudden deafness, respectively. In the controls, 10.6%, 6.1%, and 0.3% were diagnosed with vertigo (P < 0.001), tinnitus (P = 0.161), and sudden deafness (P = 0.774), respectively. Results from the multivariate logistic regression analyses showed that the risk of PAOD was significantly increased in patients with vertigo (adjusted odds ratio = 1.12, P = 0.027) but not in those with tinnitus or sudden deafness. Conclusions A modest increase in the risk of PAOD was observed among Taiwanese patients with vertigo, after adjustment for comorbidities. PMID:27631630
Sensorineural hearing loss in hemorrhagic dengue?
Ribeiro, Bruna Natália Freire; Guimarães, Alexandre Caixeta; Yazawa, Felipe; Takara, Tammy Fumiko Messias; de Carvalho, Guilherme Machado; Zappelini, Carlos Eduardo Monteiro
2015-01-01
Dengue is an acute febrile infectious disease, with high fever followed by symptoms flu-like. Dengue hemorrhagic fever (DHF) is a vascular leak syndrome and could present spontaneous bleeding and worsening of symptoms after some days. Dengue could have some ENT manifestations, however hearing loss is not one of them. Sudden hearing loss is considered as sensorineural or perceptual hearing loss with a sudden onset in a person without other prior otological history. The relation between infectious diseases and sudden hearing are been investigated, some viruses were already linked, but the relation between dengue virus and sudden hearing still remains unknown. This article has the goal of presenting a case of DHF that evolved with SSHL in his hospitalization process. We report a 60 years-male patient of with DHF who developed bilateral secretory otitis media and sensorineural hearing loss after the fifth day of onset of symptoms. His hearing loss remained even after 7 months and the patient was referred for hearing aid fitting. This is the first case report that brings together DHF and sudden hearing loss. In the development of this case no other cause to sudden hearing loss was found and the correlation between dengue and hearing loss was questioned. In the literature review was found that some viruses, as mumps virus, varicella-zoster virus and HSV-1 and HSV-2 are related to sudden hearing loss, all of them fit in the viral theory. Besides the viral theory of sudden hearing loss, there is the vascular theory that is the occlusion of the end artery that supplies the cochlea. DHF has a vascular commitment, and the hypothesis of a vascular cause could be elicited in this case. Many studies in this area are needed and this article has the objective of elicit the discussion about the subject. Could dengue be associated with sensorineural hearing loss? Copyright © 2015. Published by Elsevier Ltd.
Brusatte, Stephen L; Candeiro, Carlos R A; Simbras, Felipe M
2017-01-01
The non-avian dinosaurs died out at the end of the Cretaceous, ~66 million years ago, after an asteroid impact. The prevailing hypothesis is that the effects of the impact suddenly killed the dinosaurs, but the poor fossil record of latest Cretaceous (Campanian-Maastrichtian) dinosaurs from outside Laurasia (and even more particularly, North America) makes it difficult to test specific extinction scenarios. Over the past few decades, a wealth of new discoveries from the Bauru Group of Brazil has revealed a unique window into the evolution of terminal Cretaceous dinosaurs from the southern continents. We review this record and demonstrate that there was a diversity of dinosaurs, of varying body sizes, diets, and ecological roles, that survived to the very end of the Cretaceous (Maastrichtian: 72-66 million years ago) in Brazil, including a core fauna of titanosaurian sauropods and abelisaurid and carcharodontosaurid theropods, along with a variety of small-to-mid-sized theropods. We argue that this pattern best fits the hypothesis that southern dinosaurs, like their northern counterparts, were still diversifying and occupying prominent roles in their ecosystems before the asteroid suddenly caused their extinction. However, this hypothesis remains to be tested with more refined paleontological and geochronological data, and we give suggestions for future work.
Respiratory difficulties and breathing disorders in achondroplasia.
Afsharpaiman, S; Saburi, A; Waters, Karen A
2013-12-01
Respiratory difficulties and breathing disorders in achondroplasia are thought to underlie the increased risk for sudden infant death and neuropsychological deficits seen in this condition. This review evaluates literature regarding respiratory dysfunctions and their sequelae in patients with achondroplasia. The limited number of prospective studies of respiratory disease in achondroplasia means that observational studies and case series provide a large proportion of the data regarding the spectrum of respiratory diseases in achondroplasia and their treatments. Amongst clinical respiratory problems described, snoring is the commonest observed abnormality, but the reported incidence of obstructive sleep apnoea (OSA) shows wide variance (10% to 75%). Reported treatments of OSA include adenotonsillectomy, the use of CPAP, and surgical improvement of the airway, including mid-face advancement. Otolaryngologic manifestations are also common. Respiratory failure due to small thoracic volumes is reported, but uncommon. Mortality rate at all ages was 2.27 (CI: 1.7-3.0) with age-specific mortality increased at all ages. Sudden death was most common in infants and children. Cardiovascular events are the main cause of mortality in adults. Despite earlier recognition and treatment of respiratory complications of achondroplasia, increased mortality rates and other complications remain high. Future and ongoing evaluation of the prevalence and impact of respiratory disorders, particularly OSA, in achondroplasia is recommended. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.
Cordonnier, Aline; Barnier, Amanda J; Sutton, John
2016-01-01
Research on future thinking has emphasized how episodic details from memories are combined to create future thoughts, but has not yet examined the role of semantic scripts. In this study, participants recalled how they planned a past camping trip in Australia (past planning task) and imagined how they would plan a future camping trip (future planning task), set either in a familiar (Australia) or an unfamiliar (Antarctica) context. Transcripts were segmented into information units that were coded according to semantic category (e.g., where, when, transport, material, actions). Results revealed a strong interaction between tasks and their presentation order. Starting with the past planning task constrained the future planning task when the context was familiar. Participants generated no new information when the future camping trip was set in Australia and completed second (after the past planning task). Conversely, starting with the future planning task facilitated the past planning task. Participants recalled more information units of their past plan when the past planning task was completed second (after the future planning task). These results shed new light on the role of scripts in past and future thinking and on how past and future thinking processes interact.
A Probabilistic Approach to Fitting Period–luminosity Relations and Validating Gaia Parallaxes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sesar, Branimir; Fouesneau, Morgan; Bailer-Jones, Coryn A. L.
Pulsating stars, such as Cepheids, Miras, and RR Lyrae stars, are important distance indicators and calibrators of the “cosmic distance ladder,” and yet their period–luminosity–metallicity (PLZ) relations are still constrained using simple statistical methods that cannot take full advantage of available data. To enable optimal usage of data provided by the Gaia mission, we present a probabilistic approach that simultaneously constrains parameters of PLZ relations and uncertainties in Gaia parallax measurements. We demonstrate this approach by constraining PLZ relations of type ab RR Lyrae stars in near-infrared W 1 and W 2 bands, using Tycho- Gaia Astrometric Solution (TGAS) parallaxmore » measurements for a sample of ≈100 type ab RR Lyrae stars located within 2.5 kpc of the Sun. The fitted PLZ relations are consistent with previous studies, and in combination with other data, deliver distances precise to 6% (once various sources of uncertainty are taken into account). To a precision of 0.05 mas (1 σ ), we do not find a statistically significant offset in TGAS parallaxes for this sample of distant RR Lyrae stars (median parallax of 0.8 mas and distance of 1.4 kpc). With only minor modifications, our probabilistic approach can be used to constrain PLZ relations of other pulsating stars, and we intend to apply it to Cepheid and Mira stars in the near future.« less
NASA Technical Reports Server (NTRS)
Weisbin, C. R. (Editor)
2004-01-01
A workshop entitled, "Outstanding Research Issues in Systematic Technology Prioritization for New Space Missions," was convened on April 21-22, 2004 in San Diego, California to review the status of methods for objective resource allocation, to discuss the research barriers remaining, and to formulate recommendations for future development and application. The workshop explored the state-of-the-art in decision analysis in the context of being able to objectively allocate constrained technical resources to enable future space missions and optimize science return. This article summarizes the highlights of the meeting results.
Nuclear physics from Lattice QCD
NASA Astrophysics Data System (ADS)
Shanahan, Phiala
2017-09-01
I will discuss the current state and future scope of numerical Lattice Quantum Chromodynamics (LQCD) calculations of nuclear matrix elements. The goal of the program is to provide direct QCD calculations of nuclear observables relevant to experimental programs, including double-beta decay matrix elements, nuclear corrections to axial matrix elements relevant to long-baseline neutrino experiments and nuclear sigma terms needed for theory predictions of dark matter cross-sections at underground detectors. I will discuss the progress and challenges on these fronts, and also address recent work constraining a gluonic analogue of the EMC effect, which will be measurable at a future electron-ion collider.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schroeder, Alex
Motor fuel taxes were established to finance our nation’s transportation infrastructure, yet evolving economic, political, and technological influences are constraining this ability. At the federal level, the Highway Trust Fund (HTF), which is primarily funded by motor fuel taxes, has become increasingly dependent on general fund contributions and short-term reauthorizations to prevent insolvency. As a result, there are discussions at both the federal and state levels in which stakeholders are examining the future of motor fuel excise taxes as well as the role of electric and alternative fuel vehicles in that future. On July 1, 2015, six states increased theirmore » motor fuel tax rates.« less
Susan J. Frankel
2017-01-01
This special issue of Forest Phytophthoras serves as part of the proceedings from the Sixth Sudden Oak Death Science Symposium held June 21 -23, 2016 at Fort Mason Center in San Francisco, CA, USA. The symposium marked almost 16 years to the day that David Rizzo (UC Davis) and Matteo Garbelotto (UC Berkeley) identified the cause of sudden oak death to be a previously...
Sudden death of effective entanglement
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roszak, K.; Institute of Physics, Wroclaw University of Technology, 50-370 Wroclaw; Horodecki, P.
2010-04-15
Sudden death of entanglement is a well-known effect resulting from the finite volume of separable states. We study the case when the observer has a limited measurement capability and analyze the effective entanglement (i.e., entanglement minimized over the output data). We show that in the well-defined system of two quantum dots monitored by single-electron transistors, one may observe a sudden death of effective entanglement when real, physical entanglement is still alive. For certain measurement setups, this occurs even for initial states for which sudden death of physical entanglement is not possible at all. The principles of the analysis may bemore » applied to other analogous scenarios, such as estimation of the parameters arising from quantum process tomography.« less
Compressing turbulence and sudden viscous dissipation with compression-dependent ionization state
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davidovits, Seth; Fisch, Nathaniel J.
Turbulent plasma flow, amplified by rapid three-dimensional compression, can be suddenly dissipated under continuing compression. Furthermore, this effect relies on the sensitivity of the plasma viscosity to the temperature, μ ~ T 5 / 2 . The plasma viscosity is also sensitive to the plasma ionization state. Here, we show that the sudden dissipation phenomenon may be prevented when the plasma ionization state increases during compression, and we demonstrate the regime of net viscosity dependence on compression where sudden dissipation is guaranteed. In addition, it is shown that, compared to cases with no ionization, ionization during compression is associated withmore » larger increases in turbulent energy and can make the difference between growing and decreasing turbulent energy.« less
Compressing turbulence and sudden viscous dissipation with compression-dependent ionization state
Davidovits, Seth; Fisch, Nathaniel J.
2016-11-14
Turbulent plasma flow, amplified by rapid three-dimensional compression, can be suddenly dissipated under continuing compression. Furthermore, this effect relies on the sensitivity of the plasma viscosity to the temperature, μ ~ T 5 / 2 . The plasma viscosity is also sensitive to the plasma ionization state. Here, we show that the sudden dissipation phenomenon may be prevented when the plasma ionization state increases during compression, and we demonstrate the regime of net viscosity dependence on compression where sudden dissipation is guaranteed. In addition, it is shown that, compared to cases with no ionization, ionization during compression is associated withmore » larger increases in turbulent energy and can make the difference between growing and decreasing turbulent energy.« less
Direct reconstruction of dark energy.
Clarkson, Chris; Zunckel, Caroline
2010-05-28
An important issue in cosmology is reconstructing the effective dark energy equation of state directly from observations. With so few physically motivated models, future dark energy studies cannot only be based on constraining a dark energy parameter space. We present a new nonparametric method which can accurately reconstruct a wide variety of dark energy behavior with no prior assumptions about it. It is simple, quick and relatively accurate, and involves no expensive explorations of parameter space. The technique uses principal component analysis and a combination of information criteria to identify real features in the data, and tailors the fitting functions to pick up trends and smooth over noise. We find that we can constrain a large variety of w(z) models to within 10%-20% at redshifts z≲1 using just SNAP-quality data.
Bumetanide for autism: more eye contact, less amygdala activation.
Hadjikhani, Nouchine; Åsberg Johnels, Jakob; Lassalle, Amandine; Zürcher, Nicole R; Hippolyte, Loyse; Gillberg, Christopher; Lemonnier, Eric; Ben-Ari, Yehezkel
2018-02-26
We recently showed that constraining eye contact leads to exaggerated increase of amygdala activation in autism. Here, in a proof of concept pilot study, we demonstrate that administration of bumetanide (a NKCC1 chloride importer antagonist that restores GABAergic inhibition) normalizes the level of amygdala activation during constrained eye contact with dynamic emotional face stimuli in autism. In addition, eye-tracking data reveal that bumetanide administration increases the time spent in spontaneous eye gaze during in a free-viewing mode of the same face stimuli. In keeping with clinical trials, our data support the Excitatory/Inhibitory dysfunction hypothesis in autism, and indicate that bumetanide may improve specific aspects of social processing in autism. Future double-blind placebo controlled studies with larger cohorts of participants will help clarify the mechanisms of bumetanide action in autism.
Forecast of Future Aviation Fuels. Part 1: Scenarios
NASA Technical Reports Server (NTRS)
English, J. M.; Liu, C. Y.; Smith, J. L.; Yin, A. K. K.; Pan, G. A.; Ayati, M. B.; Gyamfi, M.; Arabzadah, M. R.
1978-01-01
A preliminary set of scenarios is described for depicting the air transport industry as it grows and changes, up to the year 2025. This provides the background for predicting the needs for future aviation fuels to meet the requirements of the industry as new basic sources, such as oil shale and coal, which are utilized to supplement petroleum. Five scenarios are written to encompass a range of futures from a serious resource-constrained economy to a continuous and optimistic economic growth. A unique feature is the choice of one immediate range scenario which is based on a serious interruption of economic growth occasioned by an energy shortfall. This is presumed to occur due to lags in starting a synfuels program.
D'Argembeau, Arnaud; Van der Linden, Martial
2004-12-01
As humans, we frequently engage in mental time travel, reliving past experiences and imagining possible future events. This study examined whether similar factors affect the subjective experience associated with remembering the past and imagining the future. Participants mentally "re-experienced" or "pre-experienced" positive and negative events that differed in their temporal distance from the present (close versus distant), and then rated the phenomenal characteristics (i.e., sensorial, contextual, and emotional details) associated with their representations. For both past and future, representations of positive events were associated with a greater feeling of re-experiencing (or pre-experiencing) than representations of negative events. In addition, representations of temporally close events (both past and future) contained more sensorial and contextual details, and generated a stronger feeling of re-experiencing (or pre-experiencing) than representations of temporally distant events. It is suggested that the way we both remember our past and imagine our future is constrained by our current goals.
2018-03-05
Arrhythmogenic Right Ventricular Cardiomyopathy; Cardiomyopathies; Heart Diseases; Cardiovascular Diseases; Sudden Cardiac Arrest; Sudden Cardiac Death; Arrhythmogenic Right Ventricular Dysplasia; Arrhythmogenic Ventricular Cardiomyopathy; Familial Dilated Cardiomyopathy; Cardiovascular Abnormalities
Modern Experience in City Combat
1987-03-01
Extensive media coverage of Beirut served to erode both domestic and international support. Surprise. As in military operations on other terrain... social reasons which constrain military actions to some degree. At the same time an empirical study has little difficulty in distinguishing in most...Review, 38-39. 39 Bureau of Applied Social Research, Columbia University. 0953). Korean urbanization: Past development and future potentials. Maxwell
Multicore Considerations for Legacy Flight Software Migration
NASA Technical Reports Server (NTRS)
Vines, Kenneth; Day, Len
2013-01-01
In this paper we will discuss potential benefits and pitfalls when considering a migration from an existing single core code base to a multicore processor implementation. The results of this study present options that should be considered before migrating fault managers, device handlers and tasks with time-constrained requirements to a multicore flight software environment. Possible future multicore test bed demonstrations are also discussed.
Morgan Grove; Laura Ogden; Steward Pickett; Chris Boone; Geoff Buckley; Dexter H. Locke; Charlie Lord; Billy Hall
2018-01-01
Legacies of social and environmental injustices can leave an imprint on the present and constrain transitions for more sustainable futures. In this article, we ask this question: What is the relationship of environmental inequality and histories of segregation? The answer for Baltimore is complex, where past practices of de jure and de facto segregation have created...
Shuang Ma; Jiang Jiang; Yuanyuan Huang; Zheng Shi; Rachel M. Wilson; Daniel Ricciuto; Stephen D. Sebestyen; Paul J. Hanson; Yiqi Luo
2017-01-01
Large uncertainties exist in predicting responses of wetland methane (CH4) fluxes to future climate change. However, sources of the uncertainty have not been clearly identified despite the fact that methane production and emission processes have been extensively explored. In this study, we took advantage of manual CH4 flux...
Teacher Tenure Has a Long History and, Hopefully, a Future
ERIC Educational Resources Information Center
Kahlenberg, Richard D.
2016-01-01
Tenure is under fire. Conservatives have long attacked such policies as tenure that constrain the ability of managers to fire whomever they want, but the latest assaults on tenure have invoked liberal egalitarian ideals. With all the problems in education, why are we so fixated on teacher tenure? What is really going on? How did tenure get its…
Cosmological measurements with general relativistic galaxy correlations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raccanelli, Alvise; Montanari, Francesco; Durrer, Ruth
We investigate the cosmological dependence and the constraining power of large-scale galaxy correlations, including all redshift-distortions, wide-angle, lensing and gravitational potential effects on linear scales. We analyze the cosmological information present in the lensing convergence and in the gravitational potential terms describing the so-called ''relativistic effects'', and we find that, while smaller than the information contained in intrinsic galaxy clustering, it is not negligible. We investigate how neglecting them does bias cosmological measurements performed by future spectroscopic and photometric large-scale surveys such as SKA and Euclid. We perform a Fisher analysis using the CLASS code, modified to include scale-dependent galaxymore » bias and redshift-dependent magnification and evolution bias. Our results show that neglecting relativistic terms, especially lensing convergence, introduces an error in the forecasted precision in measuring cosmological parameters of the order of a few tens of percent, in particular when measuring the matter content of the Universe and primordial non-Gaussianity parameters. The analysis suggests a possible substantial systematic error in cosmological parameter constraints. Therefore, we argue that radial correlations and integrated relativistic terms need to be taken into account when forecasting the constraining power of future large-scale number counts of galaxy surveys.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taddei, Laura; Martinelli, Matteo; Amendola, Luca, E-mail: taddei@thphys.uni-heidelberg.de, E-mail: martinelli@lorentz.leidenuniv.nl, E-mail: amendola@thphys.uni-heidelberg.de
2016-12-01
The aim of this paper is to constrain modified gravity with redshift space distortion observations and supernovae measurements. Compared with a standard ΛCDM analysis, we include three additional free parameters, namely the initial conditions of the matter perturbations, the overall perturbation normalization, and a scale-dependent modified gravity parameter modifying the Poisson equation, in an attempt to perform a more model-independent analysis. First, we constrain the Poisson parameter Y (also called G {sub eff}) by using currently available f σ{sub 8} data and the recent SN catalog JLA. We find that the inclusion of the additional free parameters makes the constraintsmore » significantly weaker than when fixing them to the standard cosmological value. Second, we forecast future constraints on Y by using the predicted growth-rate data for Euclid and SKA missions. Here again we point out the weakening of the constraints when the additional parameters are included. Finally, we adopt as modified gravity Poisson parameter the specific Horndeski form, and use scale-dependent forecasts to build an exclusion plot for the Yukawa potential akin to the ones realized in laboratory experiments, both for the Euclid and the SKA surveys.« less
Qasrawi, Shaden O; Pandi-Perumal, Seithikurippu R; BaHammam, Ahmed S
2017-09-01
Studies have shown that experimental fasting can affect cognitive function, sleep, and wakefulness patterns. However, the effects of experimental fasting cannot be generalized to fasting during Ramadan due to its unique characteristics. Therefore, there has been increased interest in studying the effects of fasting during Ramadan on sleep patterns, daytime sleepiness, cognitive function, sleep architecture, and circadian rhythm. In this review, we critically discuss the current research findings in those areas during the month of Ramadan. Available data that controlled for sleep/wake schedule, sleep duration, light exposure, and energy expenditure do not support the notion that Ramadan intermittent fasting increases daytime sleepiness and alters cognitive function. Additionally, recent well-designed studies showed no effect of fasting on circadian rhythms. However, in non-constrained environments that do not control for lifestyle changes, studies have demonstrated sudden and significant delays in bedtime and wake time. Studies that controlled for environmental factors and sleep/wake schedule reported no significant disturbances in sleep architecture. Nevertheless, several studies have consistently reported that the main change in sleep architecture during fasting is a reduction in the proportion of REM sleep.
Beauty is distractive: particle production during multifield inflation
NASA Astrophysics Data System (ADS)
Battefeld, Diana; Battefeld, Thorsten; Byrnes, Christian; Langlois, David
2011-08-01
We consider a two-dimensional model of inflation, where the inflationary trajectory is ``deformed'' by a grazing encounter with an Extra Species/Symmetry Point (ESP) after the observable cosmological scales have left the Hubble radius. The encounter entails a sudden production of particles, whose backreaction causes a bending of the trajectory and a temporary decrease in speed, both of which are sensitive to initial conditions. This ``modulated'' effect leads to an additional contribution to the curvature perturbation, which can be dominant if the encounter is close. We compute associated non-Gaussianities, the bispectrum and its scale dependence as well as the trispectrum, which are potentially detectable in many cases. In addition, we consider a direct modulation of the coupling to the light field at the ESP via a modulaton field, a mixed scenario whereby the modulaton is identified with a second inflaton, and an extended Extra Species Locus (ESL); all of these scenarios lead to similar additional contributions to observables. We conclude that inflaton interactions throughout inflation are strongly constrained if primordial non-Gaussianities remain unobserved in current experiments such as PLANCK. If they are observed, an ESP encounter leaves additional signatures on smaller scales which may be used to identify the model.
Simpson, Christopher S; Hoffmaster, Barry; Dorian, Paul
2005-05-15
Implantable cardioverter defibrillators have been shown to reduce all-cause mortality in some patient populations at risk of sudden death. New Canadian guidelines recommend implantable cardioverter defibrillator therapy for these patients. However, the need for these devices exceeds the funded volumes in many Canadian jurisdictions. As a result, rationing of this resource has been necessary. While rationing at the macro (Ministry of Health) and meso (hospital) levels has achieved some level of acceptance by society, the responsibility for the decisions taken at the micro (individual) patient level actually rests with the physician at the bedside. This 'bedside rationing' creates a moral dilemma for physicians, who are torn between their traditional fiduciary role as 'patient advocate' and the competing role of 'gatekeeper'. This 'downward delegation' of rationing decision-making obscures the reality that rationing occurs, and encourages covert, opaque and inconsistent approaches. The remedy is the development of fair, legitimate procedures for making rationing decisions that include guidelines that structure and constrain those decisions. Macro- and meso-level stakeholders must also recognize and take responsibility for their part in restricting resources in a broadly inclusive and transparent process.
Here Today, Gone Tomorrow – Adaptation to Change in Memory-Guided Visual Search
Zellin, Martina; Conci, Markus; von Mühlenen, Adrian; Müller, Hermann J.
2013-01-01
Visual search for a target object can be facilitated by the repeated presentation of an invariant configuration of nontargets (‘contextual cueing’). Here, we tested adaptation of learned contextual associations after a sudden, but permanent, relocation of the target. After an initial learning phase targets were relocated within their invariant contexts and repeatedly presented at new locations, before they returned to the initial locations. Contextual cueing for relocated targets was neither observed after numerous presentations nor after insertion of an overnight break. Further experiments investigated whether learning of additional, previously unseen context-target configurations is comparable to adaptation of existing contextual associations to change. In contrast to the lack of adaptation to changed target locations, contextual cueing developed for additional invariant configurations under identical training conditions. Moreover, across all experiments, presenting relocated targets or additional contexts did not interfere with contextual cueing of initially learned invariant configurations. Overall, the adaptation of contextual memory to changed target locations was severely constrained and unsuccessful in comparison to learning of an additional set of contexts, which suggests that contextual cueing facilitates search for only one repeated target location. PMID:23555038
Low energy secondary cosmic ray flux (gamma rays) monitoring and its constrains
NASA Astrophysics Data System (ADS)
Raghav, Anil; Bhaskar, Ankush; Yadav, Virendra; Bijewar, Nitinkumar
2015-02-01
Temporal variation of secondary cosmic rays (SCR) flux was measured during the full and new moon and days close to them at Department of Physics, University of Mumbai, Mumbai (Geomagnetic latitude: 10.6 °N), India. The measurements were done by using NaI (Tl) scintillation detector with energy threshold of 200 keV. The SCR flux showed sudden enhancement for approximately about 2 hour during few days out of all observations. The maximum enhancement in SCR flux is about 200 % as compared to the diurnal trend of SCR temporal variations. Weather parameters (temperature and relative humidity) were continuously monitored during all observations. The influences of geomagnetic field, interplanetary parameters and tidal effect on SCR flux have been considered. Summed spectra corresponding to enhancement duration indicates appearance of atmospheric radioactivity which shows single gamma ray line. Detail investigation revealed the presence of radioactive Ar41. Present study indicates origin of Ar41 could be due to anthropogenic source or due to gravitational tidal forces. This measurements point out limitations on low energy SCR flux monitoring. This study will help many researchers in measurements of SCR flux during eclipses and to find unknown mechanism behind decrease/increase in SCR flux during solar/lunar eclipse.
Ammonia-based feedforward and feedback aeration control in activated sludge processes.
Rieger, Leiv; Jones, Richard M; Dold, Peter L; Bott, Charles B
2014-01-01
Aeration control at wastewater treatment plants based on ammonia as the controlled variable is applied for one of two reasons: (1) to reduce aeration costs, or (2) to reduce peaks in effluent ammonia. Aeration limitation has proven to result in significant energy savings, may reduce external carbon addition, and can improve denitrification and biological phosphorus (bio-P) performance. Ammonia control for limiting aeration has been based mainly on feedback control to constrain complete nitrification by maintaining approximately one to two milligrams of nitrogen per liter of ammonia in the effluent. Increased attention has been given to feedforward ammonia control, where aeration control is based on monitoring influent ammonia load. Typically, the intent is to anticipate the impact of sudden load changes, and thereby reduce effluent ammonia peaks. This paper evaluates the fundamentals of ammonia control with a primary focus on feedforward control concepts. A case study discussion is presented that reviews different ammonia-based control approaches. In most instances, feedback control meets the objectives for both aeration limitation and containment of effluent ammonia peaks. Feedforward control, applied specifically for switching aeration on or off in swing zones, can be beneficial when the plant encounters particularly unusual influent disturbances.
2012-01-01
Background Viral myocarditis is a major cause of sudden unexpected death in children and young adults. Until recently, coxsackievirus B3 (CVB3) has been the most commonly implicated virus in myocarditis. At present, no standard diagnosis is generally accepted due to the insensitivity of traditional diagnostic tests. This has prompted health professionals to seek new diagnostic approaches, which resulted in the emergence of new molecular pathological tests and a more detailed immunohistochemical and histopathological analysis. When supplemented with immunohistochemistry and molecular pathology, conventional histopathology may provide important clues regarding myocarditis underlying etiology. Methods This study is based on post-mortem samples from sudden unexpected death victims and controls who were investigated prospectively. Immunohistochemical investigations for the detection of the enteroviral capsid protein VP1 and the characterization and quantification of myocardial inflammatory reactions as well as molecular pathological methods for enteroviral genome detection were performed. Results Overall, 48 sudden unexpected death victims were enrolled. As for controls, 37 cases of unnatural traffic accident victims were studied. Enterovirus was detected in 6 sudden unexpected death cases (12.5 %). The control samples were completely enterovirus negative. Furthermore, the enteroviral capsid protein VP1 in the myocardium was detected in enterovirus-positive cases revealed by means of reverse transcriptase-polymerase chain reaction (RT-PCR). Unlike control samples, immunohistochemical investigations showed a significant presence of T and B lymphocytes in sudden unexpected death victims. Conclusions Our findings demonstrate clearly a higher prevalence of viral myocarditis in cases of sudden unexpected death compared to control subjects, suggesting that coxsackie B enterovirus may contribute to myocarditis pathogenesis significantly. PMID:22966951
[Expression of proBNP and NT-proBNP in Sudden Death of Coronary Heart Disease].
Zeng, Q; Sun, R F; Li, Z; Zhai, L Q; Liu, M Z; Guo, X J; Gao, C R
2017-10-01
To study the expression change of pro-brain natriuretic peptide (proBNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in sudden death of coronary atherosclerotic heart disease, and to explore its application in forensic diagnosis. Myocardial and blood samples were collected from normal control group, sudden death of coronary atherosclerotic heart disease group and single coronary stenosis group (20 cases in each group). The expression of proBNP in myocardial samples were detected by immunohistochemical staining and Western blotting, and that of BNP mRNA were detected by reverse transcription PCR (RT-PCR). The content of NT-proBNP in plasma were detected by ELISA. Immunohistochemical staining showed positive expression of proBNP in both sudden death of coronary atherosclerotic heart disease group and single coronary stenosis group. There was no positive expression in normal control group. For sudden death of coronary atherosclerotic heart disease group and single coronary stenosis group, the relative expression of proBNP protein and BNP mRNA in myocardial tissue and the NT-proBNP content in plasma were higher than that of normal control group ( P <0.05). The NT-proBNP content in plasma of sudden death of coronary atherosclerotic heart disease group was higher than that of single coronary stenosis group ( P <0.05). In myocardial ischemia condition, the higher expression of proBNP in cardiac muscle cell shows that the detection of NT-proBNP in plasma can be useful to differentially diagnose the degree of coronary atherosclerotic heart disease and determine whether the sudden death due to coronary atherosclerotic heart disease. Copyright© by the Editorial Department of Journal of Forensic Medicine
High-Dose Citalopram and Escitalopram and the Risk of Out-of-Hospital Death.
Ray, Wayne A; Chung, Cecilia P; Murray, Katherine T; Hall, Kathi; Stein, C Michael
2017-02-01
Studies demonstrating that higher doses of citalopram (> 40 mg) and escitalopram (> 20 mg) prolong the corrected QT interval prompted regulatory agency warnings, which are controversial, given the absence of confirmatory clinical outcome studies. We compared the risk of potential arrhythmia-related deaths for high doses of these selective serotonin reuptake inhibitors (SSRIs) to that for equivalent doses of fluoxetine, paroxetine, and sertraline. The Tennessee Medicaid retrospective cohort study included 54,220 persons 30-74 years of age without cancer or other life-threatening illness who were prescribed high-dose SSRIs from 1998 through 2011. The mean age was 47 years, and 76% were female. Demographic characteristics and comorbidity for individual SSRIs were comparable. Because arrhythmia-related deaths are typically sudden and occur outside the hospital, we analyzed out-of-hospital sudden unexpected death as well as sudden cardiac deaths, a more specific indicator of proarrhythmic effects. The adjusted risk of sudden unexpected death for citalopram did not differ significantly from that for the other SSRIs. The respective hazard ratios (HRs) for citalopram versus escitalopram, fluoxetine, paroxetine, and sertraline were 0.84 (95% CI, 0.40-1.75), 1.24 (95% CI, 0.75-2.05), 0.75 (95% CI, 0.45-1.24), and 1.53 (95% CI, 0.91-2.55). There were no significant differences for sudden cardiac death or all study deaths, nor were there significant differences among high-risk patients (≥ 60 years of age, upper quartile baseline cardiovascular risk). Escitalopram users had no significantly increased risk for any study end point. We found no evidence that risk of sudden unexpected death, sudden cardiac death, or total mortality for high-dose citalopram and escitalopram differed significantly from that for comparable doses of fluoxetine, paroxetine, and sertraline. © Copyright 2016 Physicians Postgraduate Press, Inc.
High-Dose Citalopram and Escitalopram and the Risk of Out-of-Hospital Death
Ray, Wayne A.; Chung, Cecilia P.; Murray, Katherine T.; Hall, Kathi; Stein, C. Michael
2018-01-01
Objective Studies demonstrating higher doses of citalopram (>40mg) and escitalopram (>20mg) prolong the QTc interval prompted regulatory agency warnings, which are controversial, given the absence of confirmatory clinical outcome studies. We compared the risk of potential arrhythmia-related deaths for high doses of these SSRIs to that for equivalent doses of fluoxetine, paroxetine, and sertraline. Method The Tennessee Medicaid retrospective cohort study included 54,220 persons 30–74 years of age without cancer or other life-threatening illness prescribed high-dose SSRIs. The mean age was 47 years and 76% were female. Demographic characteristics and comorbidity for individual SSRIs were comparable. Because arrhythmia-related deaths are typically sudden and occur outside the hospital, we analyzed out-of-hospital sudden unexpected death as well as sudden cardiac deaths, a more specific indicator of pro-arrhythmic effects. Results The adjusted risk of sudden unexpected death for citalopram did not differ significantly from that for the other SSRIs. The respective hazard ratios (HRs) for citalopram versus escitalopram, fluoxetine, paroxetine, and sertraline were 0.84 (95% confidence interval [CI], 0.40–1.75), 1.24 (0.75–2.05), 0.75 (0.45–1.24), and 1.53 (0.91–2.55). There were no significant differences for sudden cardiac death or all study deaths, nor were there significant differences among high-risk patients (≥60 years of age, upper quartile baseline cardiovascular risk). Escitalopram users had no significantly increased risk for any study endpoint. Conclusions We found no evidence that risk of sudden unexpected death, sudden cardiac death, or total mortality for high-dose citalopram and escitalopram differed significantly from that for comparable doses of fluoxetine, paroxetine, and sertraline. PMID:27736049
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.
Christy, Alison; Nyhan, William; Wilson, Jenny
2017-01-01
Lesch-Nyhan disease (LND) is an X-linked disorder of purine metabolism, associated with self-mutilation, dystonia, and chorea. Seizures are uncommon in LND. Patients with LND are at risk for sudden and unexpected death. The etiology of this is unknown, but appears to occur from a respiratory process. We propose that respiratory failure secondary to subclinical seizure may lead to sudden death in these patients. We report a case of an 11-year-old boy with LND who had two episodes of nocturnal gasping. The second event was immediately followed by a 10 min generalized seizure. Upon arrival at the hospital, an arterial blood gas test revealed a severe respiratory acidosis. Following aggressive treatment of his seizures, this patient did well, and was discharged home on oxcarbazepine with rectal diazepam. No further seizures have been noted in 1 year of follow-up. In this case report and review, we hypothesize that sudden death from respiratory failure in Lesch-Nyhan disease may in some cases be due to seizure-induced respiratory failure, akin to sudden unexpected death in epilepsy (SUDEP). We suggest screening for paroxysmal respiratory events; consideration of electroencephalography for patients with LND presenting in respiratory distress or failure; and consideration of more aggressive treatment of seizures in these patients. Brief Summary:We present an 11-year-old boy with Lesch-Nyhan disease (LND) who developed respiratory failure and severe respiratory acidosis from his first known seizure, which evolved to subclinical status epilepticus. We propose that patients with LND have a predisposition to respiratory failure and sudden death, which in some cases may be provoked by seizure (sudden unexpected death in epilepsy, or SUDEP).
Cardiovascular Risk Factors in Primary Relatives of Sudden Cardiac Death Victims
1991-01-01
hypertriglyceridemia and hypertension as risk factors in relatives of sudden death victims. The sample for both studies will be the same. 5 Chapter II The...provided most of the research information on SCD. Pathology of Sudden Cardiac Death There appear to be several different pathologic scenarios which render a...had severe two or three vessel disease. By comparison, 100 age matched controls who died of other causes, had a combined 27% incidence of two and
Is there an association between depression and cardiovascular mortality or sudden death?
Alboni, Paolo; Favaron, Elisa; Paparella, Nelly; Sciammarella, Massimo; Pedaci, Mario
2008-04-01
The results of many studies and recent meta-analyses strongly suggest that depression is a risk factor for total and cardiovascular mortality, both in the general population and in patients with known heart disease. By contrast, the association between depression and sudden death or cardiac arrest has received little attention. This issue has been investigated in three recent studies; two were carried out in the general population and showed depression to be a independent risk factor for sudden death. The other study was carried out in patients with acute myocardial infarction (AMI); the adjusted relative risk (RR) of sudden death was significantly increased in depressed patients but, after adjustment for dyspnea/fatigue (a common symptom for heart disease and depression), the RR was no longer statistically significant. However, when the cognitive-affective depressive symptoms were examined separately from the somatic ones (dyspnea/fatigue, etc.), there was a clear trend for an association between cognitive-affective symptoms and sudden death. Because a risk factor can be defined as 'independent' only in a multivariate analysis in which variables are dichotomized, the presence of common symptoms between heart disease and depression represents a very difficult problem. However, taken together, the results of studies carried out in the general population and in patients with AMI strongly suggest that depression is a significant risk factor for sudden death.
Genetic and forensic implications in epilepsy and cardiac arrhythmias: a case series.
Partemi, Sara; Vidal, Monica Coll; Striano, Pasquale; Campuzano, Oscar; Allegue, Catarina; Pezzella, Marianna; Elia, Maurizio; Parisi, Pasquale; Belcastro, Vincenzo; Casellato, Susanna; Giordano, Lucio; Mastrangelo, Massimo; Pietrafusa, Nicola; Striano, Salvatore; Zara, Federico; Bianchi, Amedeo; Buti, Daniela; La Neve, Angela; Tassinari, Carlo Alberto; Oliva, Antonio; Brugada, Ramon
2015-05-01
Epilepsy affects approximately 3% of the world's population, and sudden death is a significant cause of death in this population. Sudden unexpected death in epilepsy (SUDEP) accounts for up to 17% of all these cases, which increases the rate of sudden death by 24-fold as compared to the general population. The underlying mechanisms are still not elucidated, but recent studies suggest the possibility that a common genetic channelopathy might contribute to both epilepsy and cardiac disease to increase the incidence of death via a lethal cardiac arrhythmia. We performed genetic testing in a large cohort of individuals with epilepsy and cardiac conduction disorders in order to identify genetic mutations that could play a role in the mechanism of sudden death. Putative pathogenic disease-causing mutations in genes encoding cardiac ion channel were detected in 24% of unrelated individuals with epilepsy. Segregation analysis through genetic screening of the available family members and functional studies are crucial tasks to understand and to prove the possible pathogenicity of the variant, but in our cohort, only two families were available. Despite further research should be performed to clarify the mechanism of coexistence of both clinical conditions, genetic analysis, applied also in post-mortem setting, could be very useful to identify genetic factors that predispose epileptic patients to sudden death, helping to prevent sudden death in patients with epilepsy.
Nagasawa, Sayaka; Saitoh, Hisako; Kasahara, Shiori; Chiba, Fumiko; Torimitsu, Suguru; Abe, Hiroko; Yajima, Daisuke; Iwase, Hirotaro
2018-05-31
Long QT syndrome (LQTS), a congenital genetic disorder, can cause torsades de pointes (TdP), and lethal cardiac arrhythmia may result from ingestion of cardiotoxic drugs. Methamphetamine (MP) and new psychoactive substances (NPSs) can trigger TdP due to QT prolongation, leading to sudden death. We therefore analysed variations in the LQTS-associated genes KCNQ1 (LQT1) and KCNH2 (LQT2) using cardiac blood and myocardial tissue from subjects having died suddenly during MP or NPS use to investigate the relationship between congenital genetic abnormalities and sudden death during illegal drug use. We amplified and sequenced all exons of these genes using samples from 20 subjects, half of whom had died taking MP and half after using NPSs. G643S, a KCNQ1 missense polymorphism, was significantly more common among sudden deaths involving NPSs (6 subjects) than those involving MP (1 subject) and healthy Japanese subjects (P = 0.001). Notably, synthetic cathinones were detected in 2 of 3 cases involving G643S carriers. Previous functional analyses have indicated that the G643S polymorphism in the KCNQ1 potassium channel gene causes mild I Ks channel dysfunction. Our data suggest that use of NPSs, particularly synthetic cathinones, is associated with elevated risk of serious cardiac arrhythmia and sudden death for subjects carrying KCNQ1 G643S.
2016-11-30
Ventricular Tachycardia; Ventricular Fibrillation; Sudden Cardiac Death; Coronary Angiography; Electrophysiologic Testing (EP); Catheter Ablation; Percutaneous Coronary Intervention (PCI); Internal Cardioverter Defibrillator (ICD)
NASA Technical Reports Server (NTRS)
Ungar, Eugene K.
2014-01-01
The aircraft-based Stratospheric Observatory for Infrared Astronomy (SOFIA) is a platform for multiple infrared observation experiments. The experiments carry sensors cooled to liquid helium (LHe) temperatures. A question arose regarding the heat input and peak pressure that would result from a sudden loss of the dewar vacuum insulation. Owing to concerns about the adequacy of dewar pressure relief in the event of a sudden loss of the dewar vacuum insulation, the SOFIA Program engaged the NASA Engineering and Safety Center (NESC). This report summarizes and assesses the experiments that have been performed to measure the heat flux into LHe dewars following a sudden vacuum insulation failure, describes the physical limits of heat input to the dewar, and provides an NESC recommendation for the wall heat flux that should be used to assess the sudden loss of vacuum insulation case. This report also assesses the methodology used by the SOFIA Program to predict the maximum pressure that would occur following a loss of vacuum event.
Validation of a computer case definition for sudden cardiac death in opioid users.
Kawai, Vivian K; Murray, Katherine T; Stein, C Michael; Cooper, William O; Graham, David J; Hall, Kathi; Ray, Wayne A
2012-08-31
To facilitate the use of automated databases for studies of sudden cardiac death, we previously developed a computerized case definition that had a positive predictive value between 86% and 88%. However, the definition has not been specifically validated for prescription opioid users, for whom out-of-hospital overdose deaths may be difficult to distinguish from sudden cardiac death. We assembled a cohort of persons 30-74 years of age prescribed propoxyphene or hydrocodone who had no life-threatening non-cardiovascular illness, diagnosed drug abuse, residence in a nursing home in the past year, or hospital stay within the past 30 days. Medical records were sought for a sample of 140 cohort deaths within 30 days of a prescription fill meeting the computer case definition. Of the 140 sampled deaths, 81 were adjudicated; 73 (90%) were sudden cardiac deaths. Two deaths had possible opioid overdose; after removing these two the positive predictive value was 88%. These findings are consistent with our previous validation studies and suggest the computer case definition of sudden cardiac death is a useful tool for pharmacoepidemiologic studies of opioid analgesics.
NASA Astrophysics Data System (ADS)
Wang, Cun; Zhang, Dayi; Ma, Yanhong; Liang, Zhichao; Hong, Jie
2016-08-01
Blade loss from a running turbofan rotor will introduce sudden unbalance into the dynamical system, and as a consequence leads to the rub-impact, the asymmetry of rotor and a series of interesting dynamic characteristics. The paper focuses on the theoretical study on the sudden unbalance and rub-impact caused by blade loss, in particular investigates the response of the rotor on a rotor test rig with sudden unbalance and rub-impact device designed respectively. The results reveal that the sudden unbalance will induce impact effect on the rotor, and critical speed frequency is excited in frequency spectrum. Meantime, the impact effect is more obvious for the rotor operating above critical speed. The influence of rub-impact is considered as additional constraint to the rotor, analyzed by the theory of time-varying system for the first time, and the results are evaluated by experimental tests. The study shows that great attention should be paid to the dynamical design for the overhung rotor system, additional constraint and corresponding analysis method in rub-impact need to be intensively studied.
Thyroid gland and cerebella lesions: New risk factors for sudden cardiac death in schizophrenia?
Scorza, Fulvio A; Cavalheiro, Esper A; de Albuquerque, Marly; de Albuquerque, Juliana; Cysneiros, Roberta M; Terra, Vera C; Arida, Ricardo M
2011-02-01
People with schizophrenia show a two to threefold increased risk to die prematurely than those without schizophrenia. Patients' life style, suicide, premature development of cardiovascular disease, high prevalence of metabolic syndrome and sudden cardiac death are well-known causes of the excess mortality. The exact pathophysiological cause of sudden death in schizophrenia is unknown, but it is likely that cardiac arrhythmia and respiratory abnormalities play potential role. Some antipsychotics may be associated with cardiovascular adverse events (e.g., QT interval prolongation) and lesions in specific brain regions, such as cerebella may be associated with respiratory abnormalities, suggesting that metabolic and brain dysfunction could lead to sudden cardiac death in patients with schizophrenia. However, exact knowledge regarding the association of these findings and schizophrenia is lacking. As subclinical hyperthyroidism has been linked with increased risk of cardiovascular disease and cerebella progressive atrophy has been observed in patients with schizophrenia, we propose in this paper that subclinical thyroid dysfunction and cerebella volume loss could be considered as new risk factor for sudden cardiac death in schizophrenia. Copyright © 2010 Elsevier Ltd. All rights reserved.
Bedsharing at home, breastfeeding and sudden infant death.Recommendations for health professionals
Jenik, Alejandro; Conti, Roxana
2017-10-01
The Sudden and Unexpected Infant Death Task Force together with the Subcommittee on Breastfeeding of the Sociedad Argentina de Pediatría have issued updated recommendations on bedsharing with the parents, a practice which remains controversial. Sleeping with the mother maximizes breastfeeding, which is protective against Sudden Infant Death. There is a small group of infants that have been associated with an increased risk of Sudden Infant Death and fatal sleeping accidents in certain circumstances. These hazards include parental smoking, sedating drugs or medication and alcohol consumption prior to sleep and sofa sharing situations. Bedsharing by breastfeeding mothers with their infants, in the absence of the above-mentioned risk factors, and with parents aware of how to ensure a safe infant sleep environment has not been shown to be associated with increased risk of Sudden Infant Death. This guidance does not advise on telling parents that they must never sleep with the baby, but rather instructs health professionals to give parents balanced advice to allow informed decision making, emphasizing the concept that parental room sharing without bedsharing is the safest place for the babies to sleep
Nobecourt, Estelle; Cariou, Bertrand; Lambert, Gilles; Krempf, Michel
A sudden and severe drug-induced decrease in plasma high-density lipoprotein cholesterol (HDL-C) is a rare condition. We report 2 patients with familial hypercholesterolemia treated with statins and fibrates and 2 others with mixed dyslipidemia treated with fibrates, who presented with a sudden and severe decrease in HDL-C (from -44% to -95%, compared with baseline). Three of the patients were treated with fibrates and had a sudden decrease in HDL-C after the adjunction of ezetimibe. HDL-C returned to normal levels after discontinuation of the offending therapies. In 2 of these patients, the reintroduction of ezetimibe with no fibrates did not affect HDL-C. In conclusion, we report a new profile of patients who are at risk for a sudden drop of HDL-C related to treatment with a combination of fibrates and ezetimibe. Although a sudden drop of HDL-C is a rare event, we recommend to carefully monitor plasma HDL-C in patients submitted to both drugs. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Burrage, Clare; Sakstein, Jeremy
2018-03-01
Theories of modified gravity, where light scalars with non-trivial self-interactions and non-minimal couplings to matter—chameleon and symmetron theories—dynamically suppress deviations from general relativity in the solar system. On other scales, the environmental nature of the screening means that such scalars may be relevant. The highly-nonlinear nature of screening mechanisms means that they evade classical fifth-force searches, and there has been an intense effort towards designing new and novel tests to probe them, both in the laboratory and using astrophysical objects, and by reinterpreting existing datasets. The results of these searches are often presented using different parametrizations, which can make it difficult to compare constraints coming from different probes. The purpose of this review is to summarize the present state-of-the-art searches for screened scalars coupled to matter, and to translate the current bounds into a single parametrization to survey the state of the models. Presently, commonly studied chameleon models are well-constrained but less commonly studied models have large regions of parameter space that are still viable. Symmetron models are constrained well by astrophysical and laboratory tests, but there is a desert separating the two scales where the model is unconstrained. The coupling of chameleons to photons is tightly constrained but the symmetron coupling has yet to be explored. We also summarize the current bounds on f( R) models that exhibit the chameleon mechanism (Hu and Sawicki models). The simplest of these are well constrained by astrophysical probes, but there are currently few reported bounds for theories with higher powers of R. The review ends by discussing the future prospects for constraining screened modified gravity models further using upcoming and planned experiments.
... Anxiety can also be a sudden attack of terror when there is no threat. What are anxiety ... People with panic disorder have sudden attacks of terror when there is no actual danger. Panic attacks ...
Resource Management in Constrained Dynamic Situations
NASA Astrophysics Data System (ADS)
Seok, Jinwoo
Resource management is considered in this dissertation for systems with limited resources, possibly combined with other system constraints, in unpredictably dynamic environments. Resources may represent fuel, power, capabilities, energy, and so on. Resource management is important for many practical systems; usually, resources are limited, and their use must be optimized. Furthermore, systems are often constrained, and constraints must be satisfied for safe operation. Simplistic resource management can result in poor use of resources and failure of the system. Furthermore, many real-world situations involve dynamic environments. Many traditional problems are formulated based on the assumptions of given probabilities or perfect knowledge of future events. However, in many cases, the future is completely unknown, and information on or probabilities about future events are not available. In other words, we operate in unpredictably dynamic situations. Thus, a method is needed to handle dynamic situations without knowledge of the future, but few formal methods have been developed to address them. Thus, the goal is to design resource management methods for constrained systems, with limited resources, in unpredictably dynamic environments. To this end, resource management is organized hierarchically into two levels: 1) planning, and 2) control. In the planning level, the set of tasks to be performed is scheduled based on limited resources to maximize resource usage in unpredictably dynamic environments. In the control level, the system controller is designed to follow the schedule by considering all the system constraints for safe and efficient operation. Consequently, this dissertation is mainly divided into two parts: 1) planning level design, based on finite state machines, and 2) control level methods, based on model predictive control. We define a recomposable restricted finite state machine to handle limited resource situations and unpredictably dynamic environments for the planning level. To obtain a policy, dynamic programing is applied, and to obtain a solution, limited breadth-first search is applied to the recomposable restricted finite state machine. A multi-function phased array radar resource management problem and an unmanned aerial vehicle patrolling problem are treated using recomposable restricted finite state machines. Then, we use model predictive control for the control level, because it allows constraint handling and setpoint tracking for the schedule. An aircraft power system management problem is treated that aims to develop an integrated control system for an aircraft gas turbine engine and electrical power system using rate-based model predictive control. Our results indicate that at the planning level, limited breadth-first search for recomposable restricted finite state machines generates good scheduling solutions in limited resource situations and unpredictably dynamic environments. The importance of cooperation in the planning level is also verified. At the control level, a rate-based model predictive controller allows good schedule tracking and safe operations. The importance of considering the system constraints and interactions between the subsystems is indicated. For the best resource management in constrained dynamic situations, the planning level and the control level need to be considered together.
Study participants incentives, compensation and reimbursement in resource-constrained settings.
Mduluza, Takafira; Midzi, Nicholas; Duruza, Donold; Ndebele, Paul
2013-01-01
Controversies still exists within the research fraternity on the form and level of incentives, compensation and reimbursement to study participants in resource-constrained settings. While most research activities contribute significantly to advancement of mankind, little has been considered in rewarding directly the research participants from resource-constrained areas. A study was conducted in Zimbabwe to investigate views and expectations of various stakeholders on study participation incentives, compensation and reimbursement issues. Data was collected using various methods including a survey of about 1,008 parents/guardians of school children participating in various immunological cohort studies and parasitology surveys. Community advisory boards (CABs) at 9 of the sites were also consulted. Further, information was gathered during discussions held at a basic research ethics training workshop. The workshop had 45 participants that including 40 seasoned Zimbabwean researchers and 5 international research collaborators. About 90% (907) of the study participants and guardians expected compensation of reasonable value, in view of the researchers' value and comparison to other sites regardless of economic status of the community. During discussion with researchers at a basic ethics training workshop, about 80% (32) believed that decisions on level of compensation should be determined by the local research ethics committees. While, the few international research collaborators were of the opinion that compensation should be in accordance with local guidelines, and incentives should be in line with funding. Both the CAB members and study participants expressed that there should be a clear distinction between study incentive and compensation accorded to individual and community expectations on benefits from studies. However, CABs expressed that their suggestions on incentives and compensation are often moderated by the regulatory authorities who cite fear of unknown concerns. Overall, both personal and community benefits need to be considered collectively in future studies to be conducted in resource-constrained communities. There is projected fear that recruitment in future may be a challenge, now that almost every community, has somehow been reached and participated in some form of studies. A major concern on reimbursement, compensation or incentives should be internationally pegged regardless of different economic status of the individuals or communities where the study is to be conducted.
The Detection and Attribution Model Intercomparison Project (DAMIP v1.0) contribution to CMIP6
NASA Astrophysics Data System (ADS)
Gillett, Nathan P.; Shiogama, Hideo; Funke, Bernd; Hegerl, Gabriele; Knutti, Reto; Matthes, Katja; Santer, Benjamin D.; Stone, Daithi; Tebaldi, Claudia
2016-10-01
Detection and attribution (D&A) simulations were important components of CMIP5 and underpinned the climate change detection and attribution assessments of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. The primary goals of the Detection and Attribution Model Intercomparison Project (DAMIP) are to facilitate improved estimation of the contributions of anthropogenic and natural forcing changes to observed global warming as well as to observed global and regional changes in other climate variables; to contribute to the estimation of how historical emissions have altered and are altering contemporary climate risk; and to facilitate improved observationally constrained projections of future climate change. D&A studies typically require unforced control simulations and historical simulations including all major anthropogenic and natural forcings. Such simulations will be carried out as part of the DECK and the CMIP6 historical simulation. In addition D&A studies require simulations covering the historical period driven by individual forcings or subsets of forcings only: such simulations are proposed here. Key novel features of the experimental design presented here include firstly new historical simulations with aerosols-only, stratospheric-ozone-only, CO2-only, solar-only, and volcanic-only forcing, facilitating an improved estimation of the climate response to individual forcing, secondly future single forcing experiments, allowing observationally constrained projections of future climate change, and thirdly an experimental design which allows models with and without coupled atmospheric chemistry to be compared on an equal footing.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coombe, D.A.; Snider, R.F.
1979-12-01
Rotational invariance is applied to the description of atom--diatom collisions in a translational--internal coupling scheme, to obtain energy sudden (ES), centrifugal sudden (CS), and infinite order sudden (IOS) approximations to the reduced scattering S matrix S (j-barlambda-bar;L;jlambda). The method of presentation emphasizes that the translational--internal coupling scheme is actually the more natural description of collision processes in which one or more directions are assumed to be conserved.
A Model of a Sudden-Death Field-Goal Football Game as a Sequential Duel,
1985-05-25
AD-RI58 232 A MODEL OF A SUDDEN-DEATH FIEL-D-GOAL FOOTBALL GAME AS A 1/1 SEGUENTIAL DUEL .. (U) VALE UNIV NEW HAVEN CT COWIES FOUNDATION FOR RESEARCH...author to pro- tect the tentative character of these papers. A MODEL OF A SUDDEN-DEATH FIELD-GOAL FOOTBALL GAME LUJ-. j AS A SEQUENTIAL DUEL S -ELECTE...abstraction. Yet an interesting extension of the military dueling literature appears to be feasible. Rather than claim Immediate relevance to football as
Stärk, Katharina D C; Goncalves, Vitor S P; McCluskey, Brian J; Pinto, Julio; Tsutsui, Toshiyuki; Gibbens, Jane
2017-02-01
This short communication summarizes the strengths and weaknesses of current organisational structures in government veterinary services, as well as future technical, financial and societal challenges and related necessary competencies for government veterinary services of the future as discussed by an expert panel at ISVEE2015. First, participating representatives of veterinary services of diverse geographical backgrounds and statements from the audience confirmed that non-technical skills such as ability to work in teams, adaptability to new environments and situations, social and communication skills are increasingly seen as important. The second challenge faced by veterinary services is related to capacity issues, i.e. to have enough manpower to plan and deliver according to legislation in a period of shrinking budgets. New and emerging diseases can result in sudden, massive increases in the workload of veterinary services. Technical complexity has also increased for some hazards. Staff skills in veterinary services therefore need to be continuously updated, and it is essential to establish cross technical collaboration with other sectors including food safety, public health and environment. ISVEE conferences were seen as an opportunity to provide a global platform to develop skills needed by veterinary services, now and in the future. Copyright © 2016 Elsevier B.V. All rights reserved.
The epidemiology of sudden oak death in Oregon forests
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...
... sudden blood loss, long-term diseases, kidney failure , aplastic anemia , or man-made heart valves). MCV above normal. ... sudden blood loss, long-term diseases, kidney failure, aplastic anemia, or man-made heart valves). MCH above normal. ...
Joint Force Interdependence for a Fiscally Constrained Future
2013-03-01
avoid single points of failure during operations. DoD leaders must immediately capitalize on their fiscal constraints to create opportunities for...political and organizational obstacles to achieving a sound fiscal defense policy will require a profound effort by strategic leaders to embed and... leaders . This paper will assess recent strategic guidance and concepts for intent and meaning while focusing on key terms used by leaders in these
The Future of Weapons of Mass Destruction: Their Nature and Role in 2030
2014-06-01
substantial improvements are al- lowed under the rubric of life extension. Other states are not so constrained and may find different ways to develop pure...The foregoing capabilities do not involve genetic manipulation or bioen- gineering; they utilize longstanding biological knowledge and processes. More...sophisticated understanding of biological systems (genomic and proteomic infor- mation) and processes ( genetic modification, bioengineering) for
Daniel J. Isaak; Michael K. Young; David E. Nagel; Dona L. Horan; Matthew C. Groce
2015-01-01
The distribution and future fate of ectothermic organisms in a warming world will be dictated by thermalscapes across landscapes. That is particularly true for stream fishes and cold-water species like trout, salmon, and char that are already constrained to high elevations and latitudes. The extreme climates in those environments also preclude invasions by most non-...
ARO PECASE: Information Assurance for Energy-Constrained Wireless Sensor Networks
2011-12-21
Distribution, 18th Annual IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), September 2007. 2. 2010 IEEE...received the following awards: Student Best Paper Award at the IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC...Localization in Wireless Ad Hoc Networks – Many current and future appli- cations of mobile ad hoc networks, including disaster response and event
2004-03-01
turned off. SLEEP Set the timer for 30 seconds before scheduled transmit time, then sleep the processor. WAKE When timer trips, power up the processor...slots where none of its neighbors are schedule to transmit. This allows the sensor nodes to perform a simple power man- agement scheme that puts the...routing This simple case study highlights the following crucial observation: optimal traffic scheduling in energy constrained networks requires future
Experimental constraints on metric and non-metric theories of gravity
NASA Technical Reports Server (NTRS)
Will, Clifford M.
1989-01-01
Experimental constraints on metric and non-metric theories of gravitation are reviewed. Tests of the Einstein Equivalence Principle indicate that only metric theories of gravity are likely to be viable. Solar system experiments constrain the parameters of the weak field, post-Newtonian limit to be close to the values predicted by general relativity. Future space experiments will provide further constraints on post-Newtonian gravity.
Quantum quenches in the Luttinger model and its close relatives
NASA Astrophysics Data System (ADS)
Cazalilla, M. A.; Chung, Ming-Chiang
2016-06-01
A number of results on quantum quenches in the Luttinger and related models are surveyed with emphasis on post-quench correlations. For the Luttinger model and initial gaussian states, we discuss both sudden and smooth quenches of the interaction and the emergence of a steady state described by a generalized Gibbs ensemble. Comparisons between analytics and numerics, and the question of universality or lack thereof are also discussed. The relevance of the theoretical results to current and future experiments in the fields of ultracold atomic gases and mesoscopic systems of electrons is also briefly touched upon. Wherever possible, our approach is pedagogical and self-contained. This work is dedicated to the memory of our colleague Alejandro Muramatsu.
Football injuries: current concepts.
Olson, David E; Sikka, Robby Singh; Hamilton, Abigail; Krohn, Austin
2011-01-01
Football is one of the most popular sports in the United States and is the leading cause of sports-related injury. A large focus in recent years has been on concussions, sudden cardiac death, and heat illness, all thought to be largely preventable health issues in the young athlete. Injury prevention through better understanding of injury mechanisms, education, proper equipment, and practice techniques and preseason screening may aid in reducing the number of injuries. Proper management of on-field injuries and health emergencies can reduce the morbidity associated with these injuries and may lead to faster return to play and reduced risk of future injury. This article reviews current concepts surrounding frequently seen football-related injuries.
Life Experience of Bereaved Parents After the 2014 Sewol Ferry Disaster in South Korea.
Lee, Dong Hun; Khang, Minsoo; Shin, Jiyoung; Lee, Hwa Jung; Brown, Jacqueline A
2017-01-01
The aim of this study was to identify the outcomes of parental bereavement and the changes in life experience that follow the traumatic death of a teenage child. The results of the study are aimed to assist counselors and educators who work with themes of grief and loss. From 17 in-depth interviews from parents bereaved by the Sewol ferry disaster of 2014 in South Korea, three main categories were found to capture the reality for parents after the sudden and traumatic death of a teenage child: (a) personal changes, (b) changes in close relationships, and (c) changes in social life. Recommendations for future research and potential implications were discussed.
NASA Astrophysics Data System (ADS)
Horváth, Zsolt; Keresztes, Zoltán; Kamenshchik, Alexander Yu.; Gergely, László Á.
2015-05-01
The evolution of a closed Friedmann universe filled by a tachyon scalar field with a trigonometric potential and cold dark matter (CDM) is investigated. A subset of the evolutions consistent to 1 σ confidence level with the Union 2.1 supernova data set is identified. The evolutions of the tachyon field are classified. Some of them evolve into a de Sitter attractor, while others proceed through a pseudotachyonic regime into a sudden future singularity. Critical evolutions leading to big brake singularities in the presence of CDM are found and a new type of cosmological evolution characterized by singularity avoidance in the pseudotachyon regime is presented.
Sudden Infant Death Syndrome (SIDS) and Vaccines
... this? Submit What's this? Submit Button Sudden Infant Death Syndrome (SIDS) Recommend on Facebook Tweet Share Compartir ... an international network of vaccine safety experts. SIDS deaths declined due to recommendations to put infants on ...
An earthquake happens when two blocks of the earth suddenly slip past one another. Earthquakes strike suddenly, violently, and without warning at any time of the day or night. If an earthquake occurs in a populated area, it may cause ...
... adolescent athletes may be the result of acute, traumatic injuries, such as a sudden fall, or chronic, repetitive ... that suddenly becomes worse due to an acute traumatic event. these injuries may result in various symptoms including pain, instability, ...
Work distributions for random sudden quantum quenches
NASA Astrophysics Data System (ADS)
Łobejko, Marcin; Łuczka, Jerzy; Talkner, Peter
2017-05-01
The statistics of work performed on a system by a sudden random quench is investigated. Considering systems with finite dimensional Hilbert spaces we model a sudden random quench by randomly choosing elements from a Gaussian unitary ensemble (GUE) consisting of Hermitian matrices with identically, Gaussian distributed matrix elements. A probability density function (pdf) of work in terms of initial and final energy distributions is derived and evaluated for a two-level system. Explicit results are obtained for quenches with a sharply given initial Hamiltonian, while the work pdfs for quenches between Hamiltonians from two independent GUEs can only be determined in explicit form in the limits of zero and infinite temperature. The same work distribution as for a sudden random quench is obtained for an adiabatic, i.e., infinitely slow, protocol connecting the same initial and final Hamiltonians.
Bilateral sudden sensorineural hearing loss as a presenting feature of systemic lupus erythematosus
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
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feng, Liefeng, E-mail: fengliefeng@tju.edu.cn, E-mail: lihongru@nankai.edu.cn; Yang, Xiufang; Wang, Cunda
2015-04-15
The junction behavior of different narrow band-gap multi-quantum-well (MQW) laser diodes (LDs) confirmed that the jump in the junction voltage in the threshold region is a general characteristic of narrow band-gap LDs. The relative change in the 1310 nm LD is the most obvious. To analyze this sudden voltage change, the threshold region is divided into three stages by I{sub th}{sup l} and I{sub th}{sup u}, as shown in Fig. 2; I{sub th}{sup l} is the conventional threshold, and as long as the current is higher than this threshold, lasing exists and the IdV/dI-I plot drops suddenly; I{sub th}{sup u}more » is the steady lasing point, at which the separation of the quasi-Fermi levels of electron and holes across the active region (V{sub j}) is suddenly pinned. Based on the evolutionary model of dissipative structure theory, the rate equations of the photons in a single-mode LD were deduced in detail at I{sub th}{sup l} and I{sub th}{sup u}. The results proved that the observed behavior of stimulated emission suddenly substituting for spontaneous emission, in a manner similar to biological evolution, must lead to a sudden increase in the injection carriers in the threshold region, which then causes the sudden increase in the junction voltage in this region.« less
Probing Planckian Corrections at the Horizon Scale with LISA Binaries
NASA Astrophysics Data System (ADS)
Maselli, Andrea; Pani, Paolo; Cardoso, Vitor; Abdelsalhin, Tiziano; Gualtieri, Leonardo; Ferrari, Valeria
2018-02-01
Several quantum-gravity models of compact objects predict microscopic or even Planckian corrections at the horizon scale. We explore the possibility of measuring two model-independent, smoking-gun effects of these corrections in the gravitational waveform of a compact binary, namely, the absence of tidal heating and the presence of tidal deformability. For events detectable by the future space-based interferometer LISA, we show that the effect of tidal heating dominates and allows one to constrain putative corrections down to the Planck scale. The measurement of the tidal Love numbers with LISA is more challenging but, in optimistic scenarios, it allows us to constrain the compactness of a supermassive exotic compact object down to the Planck scale. Our analysis suggests that highly spinning, supermassive binaries at 1-20 Gpc provide unparalleled tests of quantum-gravity effects at the horizon scale.
Constraining estimates of methane emissions from Arctic permafrost regions with CARVE
NASA Astrophysics Data System (ADS)
Chang, R. Y.; Karion, A.; Sweeney, C.; Henderson, J.; Mountain, M.; Eluszkiewicz, J.; Luus, K. A.; Lin, J. C.; Dinardo, S.; Miller, C. E.; Wofsy, S. C.
2013-12-01
Permafrost in the Arctic contains large carbon pools that are currently non-labile, but can be released to the atmosphere as polar regions warm. In order to predict future climate scenarios, we need to understand the emissions of these greenhouse gases under varying environmental conditions. This study presents in-situ measurements of methane made on board an aircraft during the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE), which sampled over the permafrost regions of Alaska. Using measurements from May to September 2012, seasonal emission rate estimates of methane from tundra are constrained using the Stochastic Time-Inverted Lagrangian Transport model, a Lagrangian particle dispersion model driven by custom polar-WRF fields. Preliminary results suggest that methane emission rates have not greatly increased since the Arctic Boundary Layer Experiment conducted in southwest Alaska in 1988.
Probing Planckian Corrections at the Horizon Scale with LISA Binaries.
Maselli, Andrea; Pani, Paolo; Cardoso, Vitor; Abdelsalhin, Tiziano; Gualtieri, Leonardo; Ferrari, Valeria
2018-02-23
Several quantum-gravity models of compact objects predict microscopic or even Planckian corrections at the horizon scale. We explore the possibility of measuring two model-independent, smoking-gun effects of these corrections in the gravitational waveform of a compact binary, namely, the absence of tidal heating and the presence of tidal deformability. For events detectable by the future space-based interferometer LISA, we show that the effect of tidal heating dominates and allows one to constrain putative corrections down to the Planck scale. The measurement of the tidal Love numbers with LISA is more challenging but, in optimistic scenarios, it allows us to constrain the compactness of a supermassive exotic compact object down to the Planck scale. Our analysis suggests that highly spinning, supermassive binaries at 1-20 Gpc provide unparalleled tests of quantum-gravity effects at the horizon scale.
Relativistic Particle Population and Magnetic Fields in Clusters of Galaxies
NASA Astrophysics Data System (ADS)
Kushnir, Doron
2011-08-01
We derive constrains on the cosmic ray (CR) population and magnetic fields (MF) in clusters of galaxies, based on: 1. The correlation between the radio and the X-ray luminosities: the former emitted by synchrotron of secondary electrons in a strong MF, >˜3 muG; In the core, the CR energy is ˜10^{-3} of the thermal energy; The source of CR is the accretion shock (AS), which accelerate CR with efficiency >˜1%. 2. The HXR luminosity: emitted by IC of CMB photons by electrons accelerated in AS with efficiency >˜1%. The constrains imply that gamma-ray emission from secondaries will be difficult to detect with existing/planned instruments. However, the extended emission from primary electrons might be detected by future HXR (NuStar, Simbol-X) and gamma-ray observations (Fermi, HESS, VERITAS).
Exoplanet Biosignatures: Future Directions
Bains, William; Cronin, Leroy; DasSarma, Shiladitya; Danielache, Sebastian; Domagal-Goldman, Shawn; Kacar, Betul; Kiang, Nancy Y.; Lenardic, Adrian; Reinhard, Christopher T.; Moore, William; Schwieterman, Edward W.; Shkolnik, Evgenya L.; Smith, Harrison B.
2018-01-01
Abstract We introduce a Bayesian method for guiding future directions for detection of life on exoplanets. We describe empirical and theoretical work necessary to place constraints on the relevant likelihoods, including those emerging from better understanding stellar environment, planetary climate and geophysics, geochemical cycling, the universalities of physics and chemistry, the contingencies of evolutionary history, the properties of life as an emergent complex system, and the mechanisms driving the emergence of life. We provide examples for how the Bayesian formalism could guide future search strategies, including determining observations to prioritize or deciding between targeted searches or larger lower resolution surveys to generate ensemble statistics and address how a Bayesian methodology could constrain the prior probability of life with or without a positive detection. Key Words: Exoplanets—Biosignatures—Life detection—Bayesian analysis. Astrobiology 18, 779–824. PMID:29938538
Future evolution in a backreaction model and the analogous scalar field cosmology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali, Amna; Majumdar, A.S., E-mail: amnaalig@gmail.com, E-mail: archan@bose.res.in
We investigate the future evolution of the universe using the Buchert framework for averaged backreaction in the context of a two-domain partition of the universe. We show that this approach allows for the possibility of the global acceleration vanishing at a finite future time, provided that none of the subdomains accelerate individually. The model at large scales is analogously described in terms of a homogeneous scalar field emerging with a potential that is fixed and free from phenomenological parametrization. The dynamics of this scalar field is explored in the analogous FLRW cosmology. We use observational data from Type Ia Supernovae,more » Baryon Acoustic Oscillations, and Cosmic Microwave Background to constrain the parameters of the model for a viable cosmology, providing the corresponding likelihood contours.« less
Exoplanet Biosignatures: Future Directions.
Walker, Sara I; Bains, William; Cronin, Leroy; DasSarma, Shiladitya; Danielache, Sebastian; Domagal-Goldman, Shawn; Kacar, Betul; Kiang, Nancy Y; Lenardic, Adrian; Reinhard, Christopher T; Moore, William; Schwieterman, Edward W; Shkolnik, Evgenya L; Smith, Harrison B
2018-06-01
We introduce a Bayesian method for guiding future directions for detection of life on exoplanets. We describe empirical and theoretical work necessary to place constraints on the relevant likelihoods, including those emerging from better understanding stellar environment, planetary climate and geophysics, geochemical cycling, the universalities of physics and chemistry, the contingencies of evolutionary history, the properties of life as an emergent complex system, and the mechanisms driving the emergence of life. We provide examples for how the Bayesian formalism could guide future search strategies, including determining observations to prioritize or deciding between targeted searches or larger lower resolution surveys to generate ensemble statistics and address how a Bayesian methodology could constrain the prior probability of life with or without a positive detection. Key Words: Exoplanets-Biosignatures-Life detection-Bayesian analysis. Astrobiology 18, 779-824.
NASA Astrophysics Data System (ADS)
Lin, H.; Zhang, X.; Wu, X.; Tarnas, J. D.; Mustard, J. F.
2018-04-01
Quantitative analysis of hydrated minerals from hyperspectral remote sensing data is fundamental for understanding Martian geologic process. Because of the difficulties for selecting endmembers from hyperspectral images, a sparse unmixing algorithm has been proposed to be applied to CRISM data on Mars. However, it's challenge when the endmember library increases dramatically. Here, we proposed a new methodology termed Target Transformation Constrained Sparse Unmixing (TTCSU) to accurately detect hydrous minerals on Mars. A new version of target transformation technique proposed in our recent work was used to obtain the potential detections from CRISM data. Sparse unmixing constrained with these detections as prior information was applied to CRISM single-scattering albedo images, which were calculated using a Hapke radiative transfer model. This methodology increases success rate of the automatic endmember selection of sparse unmixing and could get more accurate abundances. CRISM images with well analyzed in Southwest Melas Chasma was used to validate our methodology in this study. The sulfates jarosite was detected from Southwest Melas Chasma, the distribution is consistent with previous work and the abundance is comparable. More validations will be done in our future work.
Beyond equilibrium climate sensitivity
NASA Astrophysics Data System (ADS)
Knutti, Reto; Rugenstein, Maria A. A.; Hegerl, Gabriele C.
2017-10-01
Equilibrium climate sensitivity characterizes the Earth's long-term global temperature response to increased atmospheric CO2 concentration. It has reached almost iconic status as the single number that describes how severe climate change will be. The consensus on the 'likely' range for climate sensitivity of 1.5 °C to 4.5 °C today is the same as given by Jule Charney in 1979, but now it is based on quantitative evidence from across the climate system and throughout climate history. The quest to constrain climate sensitivity has revealed important insights into the timescales of the climate system response, natural variability and limitations in observations and climate models, but also concerns about the simple concepts underlying climate sensitivity and radiative forcing, which opens avenues to better understand and constrain the climate response to forcing. Estimates of the transient climate response are better constrained by observed warming and are more relevant for predicting warming over the next decades. Newer metrics relating global warming directly to the total emitted CO2 show that in order to keep warming to within 2 °C, future CO2 emissions have to remain strongly limited, irrespective of climate sensitivity being at the high or low end.
Laha, Ranjan; Brodsky, Stanley J.
2017-12-05
Here, the discovery of extraterrestrial neutrinos in the ~30 TeV–PeV energy range by IceCube provides new constraints on high energy astrophysics. An important background to the signal are the prompt neutrinos which originate from the decay of charm hadrons produced by high energy cosmic-ray particles interacting in the Earth’s atmosphere. It is conventional to use the calculations of charm hadroproduction using gluon splitting g → c¯c alone. However, QCD predicts an additional “intrinsic" component of the heavy quark distribution which arises from diagrams where heavy quarks are multiply connected to the proton’s valence quarks. We estimate the prompt neutrino spectrummore » due to intrinsic charm. We find that the atmospheric prompt neutrino flux from intrinsic charm is comparable to those calculated using QCD computations not including intrinsic charm, once we normalize the intrinsic charm differential cross sections to the ISR and the LEBC-MPS collaboration data. In the future, IceCube will constrain the intrinsic charm content of the proton and will contribute to one of the major questions in high energy physics phenomenology.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laha, Ranjan; Brodsky, Stanley J.
Here, the discovery of extraterrestrial neutrinos in the ~30 TeV–PeV energy range by IceCube provides new constraints on high energy astrophysics. An important background to the signal are the prompt neutrinos which originate from the decay of charm hadrons produced by high energy cosmic-ray particles interacting in the Earth’s atmosphere. It is conventional to use the calculations of charm hadroproduction using gluon splitting g → c¯c alone. However, QCD predicts an additional “intrinsic" component of the heavy quark distribution which arises from diagrams where heavy quarks are multiply connected to the proton’s valence quarks. We estimate the prompt neutrino spectrummore » due to intrinsic charm. We find that the atmospheric prompt neutrino flux from intrinsic charm is comparable to those calculated using QCD computations not including intrinsic charm, once we normalize the intrinsic charm differential cross sections to the ISR and the LEBC-MPS collaboration data. In the future, IceCube will constrain the intrinsic charm content of the proton and will contribute to one of the major questions in high energy physics phenomenology.« less
Tedder, Jacqui; Miller, Laurie; Tu, Sicong; Hornberger, Michael; Lah, Suncica
2016-02-01
Remembering the past and imaging the future are both manifestations of 'mental time travel'. These processes have been found to be impaired in patients with bilateral hippocampal lesions. Here, we examined the question of whether future thinking is affected by other Papez circuit lesions, namely: damage to the mammillary bodies/fornix. Case (SL) was a 43-year-old woman who developed dense anterograde and retrograde amnesia suddenly, as a result of Wernicke-Korsakoff's syndrome. A region of interest volumetric Magnetic resonance imaging (MRI) analysis was performed. We assessed past and future thinking in SL and 11 control subjects of similar age and education with the adapted Autobiographical Interview (AI). Participants also completed a battery of neuropsychological tests. Volumetric MRI analyses revealed severely reduced fornix and mammillary body volumes, but intact hippocampi. SL showed substantial, albeit temporally graded retrograde memory deficits on the adapted AI. Strikingly, whilst SL could not provide any specific details of events from the past two weeks or past two years and had impaired recall of events from her late 30s, her descriptions of potential future events were normal in number of event details and plausibility. This dissociation of past and future events' performance after mammillary body and fornix damage is at odds with the findings of the majority of patients with adult onset hippocampal amnesia. It suggests that these non-hippocampal regions of the Papez circuit are only critical for past event retrieval and not for the generation of possible future events.
Generalized second law of thermodynamics in f(T) gravity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Karami, K.; Abdolmaleki, A., E-mail: KKarami@uok.ac.ir, E-mail: AAbdolmaleki@uok.ac.ir
2012-04-01
We investigate the validity of the generalized second law (GSL) of gravitational thermodynamics in the framework of f(T) modified teleparallel gravity. We consider a spatially flat FRW universe containing only the pressureless matter. The boundary of the universe is assumed to be enclosed by the Hubble horizon. For two viable f(T) models containing f(T) = T+μ{sub 1}((−T)){sup n} and f(T) = T−μ{sub 2}T(1−e{sup βT{sub 0}/T}), we first calculate the effective equation of state and deceleration parameters. Then, (we investigate the null and strong energy conditions and conclude that a sudden future singularity appears in both models. Furthermore, using a cosmographicmore » analysis we check the viability of two models. Finally, we examine the validity of the GSL and find that for both models it) is satisfied from the early times to the present epoch. But in the future, the GSL is violated for the special ranges of the torsion scalar T.« less
The MJO-SSW Teleconnection: Interaction Between MJO-Forced Waves and the Midlatitude Jet
NASA Astrophysics Data System (ADS)
Kang, Wanying; Tziperman, Eli
2018-05-01
The Madden-Julian Oscillation (MJO) was shown to affect both present-day sudden stratospheric warming (SSW) events in the Arctic and their future frequency under global warming scenarios, with implications to the Arctic Oscillation and midlatitude extreme weather. This work uses a dry dynamic core model to understand the dependence of SSW frequency on the amplitude and longitudinal range of the MJO, motivated by the prediction that the MJO will strengthen and broaden its longitudinal range in a warmer climate. We focus on the response of the midlatitude jets and the corresponding generated stationary waves, which are shown to dominate the response of SSW events to MJO forcing. Momentum budget analysis of a large ensemble of spinup simulations suggests that the climatological jet response is driven by the MJO-forced meridional eddy momentum transport. The results suggest that the trends in both MJO amplitude and longitudinal range are important for the prediction of the midlatitude jet response and for the prediction of SSWs in a future climate.
Validation of a computer case definition for sudden cardiac death in opioid users
2012-01-01
Background To facilitate the use of automated databases for studies of sudden cardiac death, we previously developed a computerized case definition that had a positive predictive value between 86% and 88%. However, the definition has not been specifically validated for prescription opioid users, for whom out-of-hospital overdose deaths may be difficult to distinguish from sudden cardiac death. Findings We assembled a cohort of persons 30-74 years of age prescribed propoxyphene or hydrocodone who had no life-threatening non-cardiovascular illness, diagnosed drug abuse, residence in a nursing home in the past year, or hospital stay within the past 30 days. Medical records were sought for a sample of 140 cohort deaths within 30 days of a prescription fill meeting the computer case definition. Of the 140 sampled deaths, 81 were adjudicated; 73 (90%) were sudden cardiac deaths. Two deaths had possible opioid overdose; after removing these two the positive predictive value was 88%. Conclusions These findings are consistent with our previous validation studies and suggest the computer case definition of sudden cardiac death is a useful tool for pharmacoepidemiologic studies of opioid analgesics. PMID:22938531
Medication and Driving-Appropriate Interventions.
Hitosugi, Masahito
2017-01-01
Sudden illness while driving has been identified as a major cause of vehicle collisions, accounting for approximately 1 in 10 collisions. Because most drivers who experience sudden illnesses while driving do not perform avoidance maneuvers, the improvement of drivers' health is being promoted as a traffic safety strategy. Although stroke, heart disease, and epilepsy are common causes of sudden illness, common symptoms, such as abdominal cramps, vertigo, and syncope can also cause problems during driving. We found that regular referral to physicians was significantly less common among drivers who experienced health-related vehicle collisions or incidents. Inadequate control of chronic disease might lead to unusual symptoms and the onset of major attacks. Medications are prescribed to patients to relieve their symptoms and/or bring their diseases under control. However, pharmacists and doctors should ensure that patients are treated with appropriate medications to avoid drivers being distracted due to adverse reactions to medications. The author suggests that it is important to keep drivers in good health and administer appropriate medications if necessary. Both pharmacists and doctors should warn drivers that sudden illness or medication-associated distractions can cause vehicle collisions. Such interventions might contribute to reducing the frequency of sudden illness-related vehicle collisions.
Damage detection on sudden stiffness reduction based on discrete wavelet transform.
Chen, Bo; Chen, Zhi-wei; Wang, Gan-jun; Xie, Wei-ping
2014-01-01
The sudden stiffness reduction in a structure may cause the signal discontinuity in the acceleration responses close to the damage location at the damage time instant. To this end, the damage detection on sudden stiffness reduction of building structures has been actively investigated in this study. The signal discontinuity of the structural acceleration responses of an example building is extracted based on the discrete wavelet transform. It is proved that the variation of the first level detail coefficients of the wavelet transform at damage instant is linearly proportional to the magnitude of the stiffness reduction. A new damage index is proposed and implemented to detect the damage time instant, location, and severity of a structure due to a sudden change of structural stiffness. Numerical simulation using a five-story shear building under different types of excitation is carried out to assess the effectiveness and reliability of the proposed damage index for the building at different damage levels. The sensitivity of the damage index to the intensity and frequency range of measurement noise is also investigated. The made observations demonstrate that the proposed damage index can accurately identify the sudden damage events if the noise intensity is limited.
Electrophysiological evaluation of Wolff-Parkinson-White Syndrome
Brembilla-Perrot, Beatrice
2002-01-01
Sudden death might complicate the follow-up of symptomatic patients with the Wolff-Parkinson-White syndrome (WPW) and might be the first event in patients with asymptomatic WPW. The risk of sudden death is increased in some clinical situations. Generally, the noninvasive studies are unable to predict the risk of sudden death correctly . The electrophysiological study is the best means to detect the risk of sudden death and to evaluate the nature of symptoms. Methods used to define the prognosis of WPW are well-defined. At first the maximal rate of conduction through the accessory pathway is evaluated; programmed atrial stimulation using 1 and 2 extrastimuli delivered at different cycle lengths is then used to determine the accessory pathway refractory period and to induce a supraventricular tachycardia. These methods should be performed in the control state and repeated in adrenergic situations either during exercise test or more simply during a perfusion of small doses of isoproterenol. The induction of an atrial fibrillation with rapid conduction through the accessory pathway (> 240/min in control state, > 300/min after isoproterenol) is the sign of a form of WPW at risk of sudden death. PMID:16951730
An examination of sudden acceleration
DOT National Transportation Integrated Search
1989-01-01
This report describes the results of a study to identify and evaluate factors which could potentially cause or contribute to the occurrence of "Sudden Acceleration Incidents" (SAI). SAI are defined in this report as unintended, unexpected, high-power...
77 FR 36134 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-18
... chem- mill steps, which could result in sudden fracture and failure of the fuselage skin panels, and...-mill steps, which could result in sudden fracture and failure of the fuselage skin panels, and...
Psychosocial Aspects of the Sudden Infant Death Syndrome ("Cot Death").
ERIC Educational Resources Information Center
Bluglass, Kerry
1981-01-01
Reviews literature on reactions of parents and siblings to Sudden Infant Death Syndrome (SIDS). The prospects for prolonged, adverse reactions are considered, and professional concerns regarding abnormal adaptation are noted. (Author/DB)
Sudden Unexpected Infant Death and Sudden Infant Death Syndrome: Reducing the Risk
... the National Institute of Child Health and Human Development (NICHD) to learn more about these and other actions. Creating a Safe Sleep Environment Learn more about safe sleep environments and reducing ...
Omega-3 polyunsaturated fatty acids for cardiovascular diseases: present, past and future.
Watanabe, Yasuhiro; Tatsuno, Ichiro
2017-08-01
Large-scale epidemiological studies on Greenlandic, Canadian and Alaskan Eskimos have examined the health benefits of omega-3 fatty acids consumed as part of the diet, and found statistically significant relative reduction in cardiovascular risk in people consuming omega-3 fatty acids. Areas covered: This article reviews studies on omega-3 fatty acids during the last 50 years, and identifies issues relevant to future studies on cardiovascular (CV) risk. Expert commentary: Although a meta-analysis of large-scale prospective cohort studies and randomized studies reported that fish and fish oil consumption reduced coronary heart disease-related mortality and sudden cardiac death, omega-3 fatty acids have not yet been shown to be effective in secondary prevention trials on patients with multiple cardiovascular disease (CVD) risk factors. The ongoing long-term CV interventional outcome studies investigate high-dose, prescription-strength omega-3 fatty acids. The results are expected to clarify the potential role of omega-3 fatty acids in reducing CV risk. The anti-inflammatory properties of omega-3 fatty acids are also important. Future clinical trials should also focus on the role of these anti-inflammatory mediators in human arteriosclerotic diseases as well as inflammatory diseases.
Classical stability of sudden and big rip singularities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barrow, John D.; Lip, Sean Z. W.
2009-08-15
We introduce a general characterization of sudden cosmological singularities and investigate the classical stability of homogeneous and isotropic cosmological solutions of all curvatures containing these singularities to small scalar, vector, and tensor perturbations using gauge-invariant perturbation theory. We establish that sudden singularities at which the scale factor, expansion rate, and density are finite are stable except for a set of special parameter values. We also apply our analysis to the stability of Big Rip singularities and find the conditions for their stability against small scalar, vector, and tensor perturbations.
National Athletic Trainers' Association Position Statement: Preventing Sudden Death in Sports
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
Objective: To present recommendations for the prevention and screening, recognition, and treatment of the most common conditions resulting in sudden death in organized sports. Background: 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. Recommendations: 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. PMID:22488236
[Presentation of 2 cases of sudden deafness in patients with sickle-cell anemia and trait].
García Callejo, F J; Sebastián Gil, E; Morant Ventura, A; Marco Algarra, J
2002-05-01
We report two cases of sudden deafness which appeared during vaso-occlusive crisis of a sickle cell anaemia (homozygous form of disease) and a sickle cell trait (heterozygous form) in two males aged sixteen and twenty-two, respectively. A high erythrocyte aggregability and low deformability were proved in both young men. Although hearing disorders have been reported in this disease, a sudden onset is not common. The treatment used was useful in the removal of painful crisis and infections, but deafness did not improve in either of then.
Sudden death of distillability in qutrit-qutrit systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Song Wei; Zhu Shiliang; Chen Lin
2009-07-15
We introduce the concept of distillability sudden death, i.e., free entangled states can evolve into nondistillable (bound entangled or separable) states in finite time under local noise. We describe the phenomenon through a specific model of local dephasing noise and compare the behavior of states in terms of the Bures fidelity. Then we propose a few methods to avoid distillability sudden death of states under (general) local dephasing noise so that free entangled states can be robust against decoherence. Moreover, we find that bound entangled states are unstable in the limit of infinite time.
Mishkin, Joseph D; Saxonhouse, Sherry J; Woo, Gregory W; Burkart, Thomas A; Miles, William M; Conti, Jamie B; Schofield, Richard S; Sears, Samuel F; Aranda, Juan M
2009-11-24
Multiple clinical trials support the use of implantable cardioverter-defibrillators (ICDs) for prevention of sudden cardiac death in patients with heart failure (HF). Unfortunately, several complicating issues have arisen from the universal use of ICDs in HF patients. An estimated 20% to 35% of HF patients who receive an ICD for primary prevention will experience an appropriate shock within 1 to 3 years of implant, and one-third of patients will experience an inappropriate shock. An ICD shock is associated with a 2- to 5-fold increase in mortality, with the most common cause being progressive HF. The median time from initial ICD shock to death ranges from 168 to 294 days depending on HF etiology and the appropriateness of the ICD therapy. Despite this prognosis, current guidelines do not provide a clear stepwise approach to managing these high-risk patients. An ICD shock increases HF event risk and should trigger a thorough evaluation to determine the etiology of the shock and guide subsequent therapeutic interventions. Several combinations of pharmacologic and device-based interventions such as adding amiodarone to baseline beta-blocker therapy, adjusting ICD sensitivity, and employing antitachycardia pacing may reduce future appropriate and inappropriate shocks. Aggressive HF surveillance and management is required after an ICD shock, as the risk of sudden cardiac death is transformed to an increased HF event risk.
Crises in national leadership?
Mahathir, M
1998-01-01
In Asia, an economic crisis has occurred simultaneously with an immense increase in the prevalence of HIV/AIDS fueled by inadequate responses to the epidemic. This response has been further weakened by sudden budget cuts and changes in government priorities, and the situation has been exacerbated by its suddenness and by the fact that large numbers of people are at risk and are unemployed. Also, Asian countries are now seeking entry into the pool of countries where donors support HIV/AIDS prevention and treatment programs just as donors are reducing their aid budgets. Prevention programs are being severely compromised even before they became effective, and efforts to secure treatment are hindered by high prices, by devalued national currencies, and by an increasing trend towards the privatization of health care. In the long run, efforts to restore economic stability will be hindered by the socioeconomic impact of the HIV/AIDS pandemic. In order to improve future prospects, the leadership of all national AIDS programs must reexamine the cost effectiveness of their priorities. Such a move would target marginalized groups, reduce use of expensive mass media campaigns, increase international cooperation over issues dealing with migrant workers, create programs recognizing the crucial role of women, increase the involvement of infected people in prevention programs, recognize the long-term socioeconomic benefits of providing adequate and equitable care and treatment, and recognize the benefits of prioritizing HIV/AIDS funding.
Michalak, Zuzanna; Wright, Gabriella; Dawson, Timothy; Hilton, David; Joshi, Abhijit; Diehl, Beate; Koepp, Matthias; Lhatoo, Samden; Sander, Josemir W.; Sisodiya, Sanjay M.
2015-01-01
Aims Sudden unexpected death in epilepsy (SUDEP) is one of the leading causes of death in people with epilepsy. For classification of definite SUDEP, a post mortem (PM), including anatomical and toxicological examination, is mandatory to exclude other causes of death. We audited PM practice as well as the value of brain examination in SUDEP. Methods We reviewed 145 PM reports in SUDEP cases from four UK neuropathology centres. Data were extracted for clinical epilepsy details, circumstances of death and neuropathological findings. Results Macroscopic brain abnormalities were identified in 52% of cases. Mild brain swelling was present in 28%, and microscopic pathologies relevant to cause or effect of seizures were seen in 89%. Examination based on whole fixed brains (76.6% of all PMs), and systematic regional sampling was associated with higher detection rates of underlying pathology (P < 0.01). Information was more frequently recorded regarding circumstances of death and body position/location than clinical epilepsy history and investigations. Conclusion Our findings support the contribution of examination of the whole fixed brain in SUDEP, with high rates of detection of relevant pathology. Availability of full clinical epilepsy‐related information at the time of PM could potentially further improve detection through targeted tissue sampling. Apart from confirmation of SUDEP, complete neuropathological examination contributes to evaluation of risk factors as well as helping to direct future research into underlying causes. PMID:26300477
Qu, Mingnan; Chen, Genyun; Bunce, James A; Zhu, Xiaocen; Sicher, Richard C
2018-05-18
Plants would experience more complex environments, such as sudden heat shock (SHS) stress combined with elevated CO 2 in the future, and might adapt to this stressful condition by optimizing photosynthetic carbon metabolism (PCM). It is interesting to understand whether this acclimation process would be altered in different genotypes of maize under elevated CO 2 , and which metabolites represent key indicators reflecting the photosynthetic rates (P N ) following SHS. Although B76 had greater reduction in P N during SHS treatment, our results indicated that P N in genotype B76, displayed faster recovery after SHS treatment under elevated CO 2 than in genotype B106. Furthermore, we employed a stepwise feature extraction approach by partial linear regression model. Our findings demonstrated that 9 key metabolites over the total (35 metabolites) can largely explain the variance of P N during recovery from SHS across two maize genotypes and two CO 2 grown conditions. Of these key metabolites, malate, valine, isoleucine, glucose and starch are positively correlated with recovery pattern of P N . Malate metabolites responses to SHS were further discussed by incorporating with the activities and gene expression of three C 4 photosynthesis-related key enzymes. We highlighted the importance of malate metabolism during photosynthesis recovery from short-term SHS, and data integration analysis to better comprehend the regulatory framework of PCM in response to abiotic stress.
Wang, Zhihua; Yang, Zhaochu; Dong, Tao
2017-01-01
Rapid growth of the aged population has caused an immense increase in the demand for healthcare services. Generally, the elderly are more prone to health problems compared to other age groups. With effective monitoring and alarm systems, the adverse effects of unpredictable events such as sudden illnesses, falls, and so on can be ameliorated to some extent. Recently, advances in wearable and sensor technologies have improved the prospects of these service systems for assisting elderly people. In this article, we review state-of-the-art wearable technologies that can be used for elderly care. These technologies are categorized into three types: indoor positioning, activity recognition and real time vital sign monitoring. Positioning is the process of accurate localization and is particularly important for elderly people so that they can be found in a timely manner. Activity recognition not only helps ensure that sudden events (e.g., falls) will raise alarms but also functions as a feasible way to guide people’s activities so that they avoid dangerous behaviors. Since most elderly people suffer from age-related problems, some vital signs that can be monitored comfortably and continuously via existing techniques are also summarized. Finally, we discussed a series of considerations and future trends with regard to the construction of “smart clothing” system. PMID:28208620
Duncan, Jhodie R; Randall, Leslie L; Belliveau, Richard A; Trachtenberg, Felicia L; Randall, Bradley; Habbe, Donald; Mandell, Federick; Welty, Thomas K; Iyasu, Solomon; Kinney, Hannah C
2008-01-01
The high rate of the sudden infant death syndrome (SIDS) in American Indians in the Northern Plains (3.5/1000) may reflect the high incidence of cigarette smoking and alcohol consumption during pregnancy. Nicotine, a neurotoxic component of cigarettes, and alcohol adversely affect nicotinic receptor binding and subsequent cholinergic development in animals. We measured (3)H-nicotine receptor binding in 16 brainstem nuclei in American Indian SIDS (n = 27) and controls (n = 6). In five nuclei related to cardiorespiratory control, (3)H-nicotinic binding decreased with increasing number of drinks (P < 0.03). There were no differences in binding in SIDS compared with controls, except upon stratification of prenatal exposures. In three mesopontine nuclei critical for arousal there were reductions (P < 0.04) in binding in controls exposed to cigarette smoke compared with controls without exposure; there was no difference between SIDS cases with or without exposure. This study suggests that maternal smoking and alcohol affects (3)H-nicotinic binding in the infant brainstem irrespective of the cause of death. It also suggests that SIDS cases are unable to respond to maternal smoking with the "normal" reduction seen in controls. Future studies are needed to establish the role of adverse prenatal exposures in altered brainstem neurochemistry in SIDS.
Wang, Zhihua; Yang, Zhaochu; Dong, Tao
2017-02-10
Rapid growth of the aged population has caused an immense increase in the demand for healthcare services. Generally, the elderly are more prone to health problems compared to other age groups. With effective monitoring and alarm systems, the adverse effects of unpredictable events such as sudden illnesses, falls, and so on can be ameliorated to some extent. Recently, advances in wearable and sensor technologies have improved the prospects of these service systems for assisting elderly people. In this article, we review state-of-the-art wearable technologies that can be used for elderly care. These technologies are categorized into three types: indoor positioning, activity recognition and real time vital sign monitoring. Positioning is the process of accurate localization and is particularly important for elderly people so that they can be found in a timely manner. Activity recognition not only helps ensure that sudden events (e.g., falls) will raise alarms but also functions as a feasible way to guide people's activities so that they avoid dangerous behaviors. Since most elderly people suffer from age-related problems, some vital signs that can be monitored comfortably and continuously via existing techniques are also summarized. Finally, we discussed a series of considerations and future trends with regard to the construction of "smart clothing" system.
[Analyses of clinical features and efficacy of sudden deafness with vertigo and dizziness].
Liu, Bo; Han, Demin; Zhang, Yi; Li, Yongxin; Gong, Shusheng; Chen, Xiuwu; Meng, Xixi; Tang, Junxiang; Xiang, Jie; Jiang, Xuejun; Yang, Ning; Tian, Ying; Hui, Lian; Feng, Shuai
2015-06-01
To investigate the clinical characteristics and the effect of drug treatment for sudden hearing loss with vertigo or dizziness. In a prospective, randomized, single blinded randomized multicenter clinical study, patients with sudden deafness, ranging in age from 18 to 65 years old, with a duration less than 2 weeks, and with no any medical treatments were collected. In accordance with the hearing curve, those patients were divided into four types, i.e., low and intermediate frequency descent type; high frequency descent type; fall flat type; and total deafness type. Each type was treated by four different treatment options, according to the unified design of the random table, and randomly selected one of the options for treatment. The efficacy of the patients with sudden deafness with vertigo and dizziness was analyzed statistically after the follow-up for 4 weeks. SPSS 13.0 software was used to analyze the data. In August 2007 to October 2011, 33 hospitals in the country included 1 024 patients with sudden deafness in line with the inclusion criteria, of whom 296 (28.91%) were accompanied by vertigo/dizziness symptoms, 126 were males and 170 were females, with an average age of (41.2 ± 13.5) years old. types of the different audiometric curves of sudden deafness, the occurrence of complete deafness with vertigo/dizziness was the highest (44.93%), followed by flat down type (25.87%), high frequency descent type (21.28%) and low intermediate frequency descent type (18.54%). After the standard treatment, the vertigo and dizziness symptoms of the sudden deafness patients could disappear, and the hearing in each group was obviously improved. The hearing curative effect on patients accompanied by vertigo/dizziness of low frequency and intermediate frequency descent type was the best, and the total efficiency can reach up to 94.74%, with the cure rate of 68.42%; followed by flat type, in which the total effective rate was 80.76%, with the recovery rate of 22.12%; and the effects on patients in high frequency descent type and total deafness type effect were relatively poor, in which the total effective rates were 70.00% (recovery rate of 10.00%) and 65.32% (recovery rate of 5.65%), respectively. The total effective rate of patients with sudden deafness associated with halo had no statistical significance (P > 0.05), in comparison to that of patients without halo; but, the cure rate of patients with no vertigo/dizziness of total deafness and the high frequency decreased patients with sudden deafness was significantly higher than that of vertigo/dizziness patients, with a statistical difference (P < 0.05). The patients with sudden deafness in each type have a certain proportion of vertigo/dizziness, especially the deaf type. The possibility of hearing complete recovery in patients with vertigo/dizziness was significantly lower than that without vertigo/dizziness.
HYDROSTATIC PRESSURE AND TEMPERATURE IN RELATION TO STIMULATION AND CYCLOSIS IN NITELLA FLEXILIS
Harvey, E. Newton
1942-01-01
Nitella flexilis cells are not stimulated to "shock stoppage" of cyclosis by suddenly evacuating the air over the water or on sudden readmission of air, or on suddenly striking a piston in the water-filled chamber in which they are kept with a ball whose energy is 7.6 joules, provided the Nitella cell is not moved by currents against the side of the chamber. Sudden increases in hydrostatic pressure from zero to 1000 lbs. or 0 to 5000 lbs. per square inch or 5000 to 9000 lbs. per square inch usually do not stimulate to "shock stoppage" of cyclosis, but some cells are stimulated. Sudden decreases of pressure are more likely to stimulate, again with variation depending on the cell. In the absence of stimulation, the cyclosis velocity at 23°C. slows as the pressure is increased in steps of 1000 lbs. per square inch. In some cells a regular slowing is observed, in others there is little slowing until 4000 to 6000 lbs. per square inch, when a rapid slowing appears, with only 50 per cent to 30 per cent of the original velocity at 9000 lbs. per square inch. The cyclosis does not completely stop at 10000 lbs. per square inch. The pressure effect is reversible unless the cells have been kept too long at the high pressure. At low temperatures (10°C.) and at temperatures near and above (32°–38°C.) the optimum temperature for maximum cyclosis (35–36°C.) pressures of 3000 to 6000 lbs. per square inch cause only further slowing of cyclosis, with no reversal of the temperature effect, such as has been observed in pressure-temperature studies on the luminescence of luminous bacteria. Sudden increase in temperature may cause shock stoppage of cyclosis as well as sudden decrease in temperature. PMID:19873318
Incidence and Etiology of Sudden Cardiac Death: New Updates for Athletic Departments.
Asif, Irfan M; Harmon, Kimberly G
Sudden cardiac death (SCD) in a young athlete is a tragic event and is the leading medical cause of death in this population. The precise incidence of SCD in young athletes has been subject of debate, with studies reporting drastically different rates (1:917,000 athlete-years (AYs) to 1:3000 AYs) depending on the methodological design of the investigation or the targeted population. A literature search was performed in PubMed using the terms: incidence, sudden cardiac death, sudden death, sudden cardiac arrest, etiology, pathology, registry, athlete, young, children, and adolescents. Articles were reviewed for relevance and included if they contained information on the incidence of SCD in athletes or young persons up to the age of 35 years. Clinical review. Level 5. Studies of high quality and rigor consistently yield an incidence of 1:50,000 AYs in college athletes and between 1:50,000 and 1:80,000 AYs for high school athletes, with certain subgroups that appear to be at particularly high risk, including the following: men, basketball players, and African Americans. Initial reports suggest that the most common cause of SCD is hypertrophic cardiomyopathy (HCM). However, more comprehensive investigations in the United States and international populations-athletes, nonathletes, and military-support that the most common finding on autopsy in young individuals with SCD is actually a structurally normal heart (autopsy-negative sudden unexplained death). SCD is the leading cause of death in athletes during exercise and usually results from intrinsic cardiac conditions that are triggered by the physiologic demands of vigorous exercise. Current rates of SCD appear to be at least 4 to 5 times higher than previously estimated, with men, African Americans, and male basketball players being at greatest risk. Emerging data suggest that the leading finding associated with SCD in athletes is actually a structurally normal heart (autopsy-negative sudden unexplained death).
[The forensic medical aspects of sudden cardiac death among the athletes].
Khodasevich, L S; Kuzin, S G; Khodasevich, A L
2012-01-01
The present review is focused on the main causes responsible for cardiac death among the athletes and the clinico-morphological characteristics of various forms of cardiac pathology leading to sudden death in the athletes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grinev, Timur; Brumer, Paul
2015-12-28
Molecular excitation with incoherent light is examined using realistic turn-on time scales, and results are compared to those obtained via commonly used sudden turn-on, or pulses. Two significant results are obtained. First, in contrast to prior studies involving sudden turn-on, realistic turn-on is shown to lead to stationary coherences for natural turn-on time scales. Second, the time to reach the final stationary mixed state, known to result from incoherent excitation, is shown to depend directly on the inverse of the molecular energy level spacings, in both sudden and realistic turn-on cases. The S{sub 0} → S{sub 2}/S{sub 1} internal conversionmore » process in pyrazine is used as an example throughout. Implications for studies of natural light harvesting systems are noted.« less
Risk stratification for sudden death in arrhythmogenic right ventricular cardiomyopathy.
Cadrin-Tourigny, Julia; Tadros, Rafik; Talajic, Mario; Rivard, Lena; Abadir, Sylvia; Khairy, Paul
2015-06-01
Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC) is an uncommon but increasingly recognized inherited cardiomyopathy that is associated with malignant ventricular arrhythmias and sudden cardiac death, particularly in young individuals. The implantable cardioverter-defibrillator (ICD) is widely regarded as the only treatment modality with evidence to support improved survival in patients with ARVC and secondary prevention indications. In contrast, there is no universally accepted risk stratification scheme to guide ICD therapy for primary prevention against sudden cardiac death. Potential benefits must be weighed against the considerable risks of complications and inappropriate shocks in this young patient population. This article tackles the challenges of risk stratification for sudden cardiac death in ARVC and critically appraises available evidence for various proposed risk factors. The authors' over-arching objective is to provide the clinician with evidence-based guidance to inform decisions regarding the selection of appropriate candidates with ARVC for ICD therapy.
Sudden death in Lesch-Nyhan disease.
Neychev, Vladimir Kostadinov; Jinnah, H A
2006-11-01
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.
Stratification of the Risk of Sudden Death in Nonischemic Heart Failure
Pimentel, Maurício; Zimerman, Leandro Ioschpe; Rohde, Luis Eduardo
2014-01-01
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. PMID:25352509
The serotonin axis: Shared mechanisms in seizures, depression and SUDEP
Richerson, George B.; Buchanan, Gordon F.
2010-01-01
Summary There is a growing appreciation that patients with seizures are also affected by a number of co-morbid conditions, including an increase in prevalence of depression (Kanner, 2009), sleep apnea (Chihorek et al, 2007), and sudden death (Ryvlin et al, 2006; Tomson et al, 2008). The mechanisms responsible for these associations are unclear. Here we discuss the possibility that underlying pathology in the serotonin (5-HT) system of epilepsy patients lowers the threshold for seizures, while also increasing the risk of depression and sudden death. We propose that post-ictal dysfunction of 5-HT neurons causes depression of breathing and arousal in some epilepsy patients, and this can lead to sudden unexpected death in epilepsy (SUDEP). We further draw parallels between SUDEP and sudden infant death syndrome (SIDS), which may share pathophysiological mechanisms, and which have both been linked to defects in the 5-HT system. PMID:21214537
Hepatic Hemangioendothelioma Presenting as Sudden Unexpected Death in Infancy: A Case Report
Dempers, Johan; Wadee, Shabbir Ahmed; Boyd, Theonia; Wright, Colleen; OdendaaL, Hein J; Sens, Mary Ann
2014-01-01
The classification of an unexpected infant death as the sudden infant death syndrome (SIDS) depends upon a complete autopsy, death scene investigation and review of medical history to exclude known causes of death. Death from occult neoplastic disease in infancy is extremely rare but is within the broad differential of SIDS. We report the sudden and unexpected death of a one-month-old infant from a hepatic (infantile) hemangioendothelioma. The physiologic mechanism of death was likely cardiac failure induced by the circulatory demands of this large vascular tumor and respiratory compromise from diaphragmatic thoracic incursion. The clinical progression and pathology of these relatively common tumors of infant livers are extremely variable. This case dramatically illustrates the potential for fatal outcome of this tumor, as well as the need for the autopsy to determine the cause of sudden and unexpected death in an infant PMID:20465426
Left Ventricular Aneurysm: Sudden Unexpected Deaths in a 29-Year-Old Man.
Srettabunjong, Supawon
2018-05-01
Left ventricular aneurysm (LVA) is an abnormal dilated heart structure, either congenital or acquired. LVA is a rare cardiac condition with no symptoms in most cases, thus occasionally diagnosed during investigations of other diseases. Its association with certain cardiac complications and sudden cardiac deaths has been reported. However, its role as a cause of sudden unexpected death is rare. The author reported a sudden cardiac death in a 29-year-old man with LVA. Without a significant coronary artery disease and known etiologies of LVA, such an abnormal heart structure in the present case was considered congenital LVA. As no other possible mechanisms of death could be identified other than LVA with its associated pathologic lesions, mural thrombi, and dilated cardiomegaly, his death was attributable to fatal cardiac arrhythmia (most commonly ventricular tachycardia) secondary to LVA. © 2017 American Academy of Forensic Sciences.
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
Ignored Disease or Diagnostic Dustbin? Sudden Infant Death Syndrome in the British Context
Ferguson, Angus H.
2015-01-01
Sudden Infant Death Syndrome (SIDS) was defined in 1969 and incorporated into the International Classification of Diseases a decade later. To advocates of SIDS as a diagnosis, medical interest in sudden infant death was long overdue. However, the definition of SIDS lacked positive diagnostic criteria, provoking some to view it as a ‘diagnostic dustbin’ for the disposal of problematic cases where cause of death was unclear. This paper examines the development of medical interest in sudden infant death in Britain during the middle decades of the twentieth century. It highlights the importance of recognising the historicity of SIDS as a diagnosis facilitated by changes in law and medicine over the course of the nineteenth and twentieth centuries. It suggests that SIDS provides a definitive case study of the medicalisation of life and death, and a unique example of an officially recognised disease that had no symptoms, signs, pathology or patients. PMID:26217070
Cosmic Rays Variation Before Changes in Sun-Earth Environment
NASA Astrophysics Data System (ADS)
Mukherjee, S.
2011-12-01
Influence of cosmic rays variations on the Sun-Earth Environment has been observed before the changes in the atmospheric temperature, outbreak of influenza, cyclone, earthquake and tsunami. It has been recorded by Sun Observatory Heleospheric Observatory (SOHO) satellite data. Before the earthquake and tsunami the planetary indices (Kp) and Electron flux (E-flux) shows sudden changes followed by the atmospheric perturbations including very high temperature rise to sudden fall resulting snowfall in high altitude and rainfall in tropical areas. The active fault zones shows sudden faulting after the sudden drop in cosmic ray intensity and rise in Kp and E-flux. Besides the geo-environment the extraterrestrial influence on outbreak of H1N1 influenza has also been recorded based on the Mexico Cosmic ray data and its correlation with SOHO records. Distant stars have the potential to influence the heliophysical parameters by showering cosmic rays.
Episodicity of Orogeny Revisited
NASA Astrophysics Data System (ADS)
Condie, K. C.; Aster, R. C.
2008-12-01
Although it is well established that orogeny is episodic, the duration, correlation and geographic distribution of orogenic episodes is not well constrained. Using large numbers of concordant U/Pb zircon ages from subduction-related granitoids (> 7000), it is now possible to better constrain these variables. Monte Carlo simulation probabilistic histograms of zircon age spectra remove questionable and spurious age peaks, yet allow resolution of peaks with >10 My duration with the data sets. Orogenic episodes with durations < 20 My, herein called pulses, are generally of regional geographic extent, whereas long-lived events (100-250 My), herein called periods, may be of regional or global extent. Orogenic periods comprise several to many pulses. Most orogenic pulses reflect geographic variations in intensity of subduction or/and plate collisions as for instance recorded around the perimeter of the Pacific basin in the last 100 My. Neither of the widely recognized pulses at 2.7 nor 1.9 Ga is global in extent. Orogenic pulses at 2700 and 2680 Ma occur on four continents each (2700: Superior, Hearne-Rae, Nain, North China; 2680: Yilgarn, Africa, Slave, Wyoming). Likewise, an orogenic pulse at 1880 is found on four continents (Laurentia, Baltica, East Asia, South America), and another pulse at 1860 Ma occurs on three continents (Africa, Siberia, Australia). Some orogenic pulses track lateral continental growth, such as 2730, 2715, and 2700 Ma pulses in the Abitibi greenstone belt, and 850, 800 and 750 Ma pulses in the Arabian-Nubian shield. Major orogenic periods are recognized at 2750-2650, 1900-1650, and 1250-1000 Ma and each of these is associated with supercontinent formation. Orogenic periods at 2600-2500 (China and India) and 2150-2050 Ma (West Africa, Amazonia, Rio de la Plata) may be associated with the formation of small supercontinents. Our results suggest that orogenic periods with intervening gaps may not require sudden and short-lived changes in mantle behavior, but may be associated primarily with the supercontinent cycle, and thus be a characteristic feature of planets with plate tectonics.
Rewriting Ice Sheet "Glacier-ology"
NASA Astrophysics Data System (ADS)
Bindschadler, R.
2006-12-01
The revolution in glaciology driven by the suite of increasingly sophisticated satellite instruments has been no more extreme than in the area of ice dynamics. Years ago, glaciologists were (probably unwittingly) selective in what properties of mountain glaciers were also applied to ice sheets. This reinforced the view that they responded slowly to their environment. Notions of rapid response driven by the ideas of John Mercer, Bill Budd and Terry Hughes were politely rejected by the centrists of mainstream glaciological thought. How the tables have turned--and by the ice sheets themselves, captured in the act of rapidly changing by modern remote sensors! The saw-toothed record of sea-level change over past glacial-interglacial cycles required the existence of rapid ice loss processes. Satellite based observations, supported by hard-earned field observations have extended the time scale over which ice sheets can suddenly change to ever shorter intervals: from centuries, to decades, to years to even minutes. As changes continue to be observed, the scientific community is forced to consider new or previously ignored processes to explain these observations. The penultimate goal of ice-sheet dynamics is to credibly predict the future of both the Greenland and Antarctic ice sheets. In this important endeavor, there is no substitute for our ability to observe. Without the extensive data sets provided by remote sensing, numerical models can be neither tested nor improved. The impact of remote sensing on our existing ability to predict the future must be compared to our probable state of knowledge and ability were these data never collected. Among many satellite observed phenomena we would be largely or wholly ignorant of are the recent acceleration of ice throughout much of coastal Greenland; the sudden disintegration of multiple ice shelves along the Antarctic Peninsula; and the dramatic thinning and acceleration of the Amundsen Sea sector of West Antarctica. These observations are driving increased concern about rapidly increasing sea level, a process dominated by ice-sheet dynamics and largely identified, quantified, studied and monitored by satellite sensors.
Evidence of strong proton shape fluctuations from incoherent diffraction
Mantysaari, H.; Schenke, B.
2016-07-25
We show within the saturation framework that measurements of exclusive vector meson production at high energy provide evidence for strong geometric fluctuations of the proton. In comparison, the effect of saturation scale and color charge fluctuations is weak. This knowledge will allow detailed future measurements of the incoherent cross section to tightly constrain the fluctuating geometry of the proton as a function of the parton momentum fraction x.
Weapon Acquisition Program Outcomes and Efforts to Reform DOD’s Acquisition Process
2016-05-09
portfolio’s total estimated acquisition cost. 11. The equity prices of contractors delivering the ten costliest programs performed well relative to broad...cost growth. • In a constrained funding environment, unforeseen cost increases limit investment choices. The equity prices of the contractors ...remain profitable well into the future • Five publicly-traded defense contractors are developing and delivering the ten largest DOD programs in the 2015
Capabilities for Constrained Military Operations
2016-12-01
capabilities that have low technology risk and accomplish all of this on a short timeline. I fully endorse all of the recommendations contained in...for the U.S. to address such conflicts. The good news is that The DoD can prevail with inexpensive capabilities that have low technology risk and on a...future actions. The Study took a three-pronged approach to countering potential adversaries’ strategies for waging long-term campaigns for
Historical Carbon Dioxide Emissions Caused by Land-Use Changes are Possibly Larger than Assumed
NASA Technical Reports Server (NTRS)
Arneth, A.; Sitch, S.; Pongratz, J.; Stocker, B. D.; Ciais, P.; Poulter, B.; Bayer, A. D.; Bondeau, A.; Calle, L.; Chini, L. P.;
2017-01-01
The terrestrial biosphere absorbs about 20% of fossil-fuel CO2 emissions. The overall magnitude of this sink is constrained by the difference between emissions, the rate of increase in atmospheric CO2 concentrations, and the ocean sink. However, the land sink is actually composed of two largely counteracting fluxes that are poorly quantified: fluxes from land-use change andCO2 uptake by terrestrial ecosystems. Dynamic global vegetation model simulations suggest that CO2 emissions from land-use change have been substantially underestimated because processes such as tree harvesting and land clearing from shifting cultivation have not been considered. As the overall terrestrial sink is constrained, a larger net flux as a result of land-use change implies that terrestrial uptake of CO2 is also larger, and that terrestrial ecosystems might have greater potential to sequester carbon in the future. Consequently, reforestation projects and efforts to avoid further deforestation could represent important mitigation pathways, with co-benefits for biodiversity. It is unclear whether a larger land carbon sink can be reconciled with our current understanding of terrestrial carbon cycling. Our possible underestimation of the historical residual terrestrial carbon sink adds further uncertainty to our capacity to predict the future of terrestrial carbon uptake and losses.
Dynamic interneuron-principal cell interplay leads to a specific pattern of in vitro ictogenesis.
Lévesque, Maxime; Chen, Li-Yuan; Hamidi, Shabnam; Avoli, Massimo
2018-07-01
Ictal discharges induced by 4-aminopyridine in the in vitro rodent entorhinal cortex present with either low-voltage fast or sudden onset patterns. The role of interneurons in initiating low-voltage fast onset ictal discharges is well established but the processes leading to sudden onset ictal discharges remain unclear. We analysed here the participation of interneurons (n = 75) and principal cells (n = 13) in the sudden onset pattern by employing in vitro tetrode wire recordings in the entorhinal cortex of brain slices from Sprague-Dawley rats. Ictal discharges emerged from a background of frequently occurring interictal spikes that were associated to a specific interneuron/principal cell interplay. High rates of interneuron firing occurred 12 ms before interictal spike onset while principal cells fired later during low interneuron firing. In contrast, the onset of sudden ictal discharges was characterized by increased firing from principal cells 627 ms before ictal onset whereas interneurons increased their firing rates 161 ms before ictal onset. Our data show that sudden onset ictogenesis is associated with frequently occurring interictal spikes resting on the interplay between interneurons and principal cells while ictal discharges stem from enhanced principal cell firing leading to increased interneuron activity. These findings indicate that specific patterns of interactions between interneurons and principal cells shape interictal and ictal discharges with sudden onset in the rodent entorhinal cortex. We propose that specific neuronal interactions lead to the generation of distinct onset patterns in focal epileptic disorders. Copyright © 2018 Elsevier Inc. All rights reserved.
A computer case definition for sudden cardiac death.
Chung, Cecilia P; Murray, Katherine T; Stein, C Michael; Hall, Kathi; Ray, Wayne A
2010-06-01
To facilitate studies of medications and sudden cardiac death, we developed and validated a computer case definition for these deaths. The study of community dwelling Tennessee Medicaid enrollees 30-74 years of age utilized a linked database with Medicaid inpatient/outpatient files, state death certificate files, and a state 'all-payers' hospital discharge file. The computerized case definition was developed from a retrospective cohort study of sudden cardiac deaths occurring between 1990 and 1993. Medical records for 926 potential cases had been adjudicated for this study to determine if they met the clinical definition for sudden cardiac death occurring in the community and were likely to be due to ventricular tachyarrhythmias. The computerized case definition included deaths with (1) no evidence of a terminal hospital admission/nursing home stay in any of the data sources; (2) an underlying cause of death code consistent with sudden cardiac death; and (3) no terminal procedures inconsistent with unresuscitated cardiac arrest. This definition was validated in an independent sample of 174 adjudicated deaths occurring between 1994 and 2005. The positive predictive value of the computer case definition was 86.0% in the development sample and 86.8% in the validation sample. The positive predictive value did not vary materially for deaths coded according to the ICO-9 (1994-1998, positive predictive value = 85.1%) or ICD-10 (1999-2005, 87.4%) systems. A computerized Medicaid database, linked with death certificate files and a state hospital discharge database, can be used for a computer case definition of sudden cardiac death. Copyright (c) 2009 John Wiley & Sons, Ltd.
Roohi, Fereydoon; Gropen, Toby; Kula, Roger W.
2014-01-01
Background: Chiari malformation type 1 (CM1) is a common congenital anomaly of the craniocervical junction. CM1 is reported to run a usually benign course and patients typically experience no symptoms or chronic, slowly progressive symptoms. However, recent reports indicate that a subset of patients with CM1 may present with acute deterioration and sudden unexpected death (SUD). We report a case of SUD during sleep in a young man with CM1, which we believe was related to the administration of common and therapeutic doses of narcotic analgesics for the management of pain. We will clarify the pathophysiology of acute deterioration and SUD in CM1 and the possibility that the adverse effects of opiate analgesics likely were the leading cause of death in our patient. Case Description: In this review, we present a 29-year-old male with worsening headache secondary to previously diagnosed CM1. The patient died suddenly and unexpectedly after administration of common and therapeutic doses of narcotic analgesics for the management of pain. Conclusion: The mechanism(s) of acute neurological deterioration and sudden death in patients with CM1 remains poorly understood. We believe the rapid fatal deterioration in our patient following administration of opioids suggests that this category of medication may cause sudden unexpected “neurogenic” cardiac death in CM1 patients by inducing sleep-related breathing difficulties and associated hypercapnia. Hypercapnia by further increasing intracranial pressure can result in a sudden pressure-induced decompensation of the cardiopulmonary control centers in the brain stem and cause instantaneous cardiorespiratory arrest. PMID:24778905
NASA Astrophysics Data System (ADS)
Heki, K.; Ping, J.
2004-12-01
Ionospheric disturbances have been detected after, e.g. Northridge (Calais and Minster, 1995) and Denali (Ducic et al., 2003) earthquakes. Similar signals observed after the 2003 Tokachi-Oki Earthquake, the largest earthquake in Japan after the completion of GEONET, a nationwide array composed of over 1000 CGPS stations. We followed a standard procedure: applying a band-pass filter for the ionospheric combination of the L1 and L2 phase signals and calculating subioonospheric points (SIP) assuming thin ionosphere at the height of 350 km. Owing to the high density of SIP, many interesting features are observed and several important parameters were constrained, e.g. (1) apparent propagation speed, (2) directivity of disturbance signals, (3) decay during propagation, etc. As for (1), the observed speed of about 1 km/sec is significantly smaller than the Rayleigh Wave velocity, significantly faster than Travelling Ionospheric Disturbances (TID), but is consistent with the sound velocity at the ionospheric heights. The acoustic wave generated by sudden vertical movement of the Earth's surface first propagate upward. Then it will be refracted by height-dependent velocity structure resulting in horizontally propagating wave through the ionosphere. The observed TEC variation, with a wavelength of a few hundred km, may reflect electron density oscillation caused by the passage of such an acoustic wave. Regarding (2), there was a clear indication that the wave does not propagate northward. As first suggested by Calais et al. (1998), such a blocking is considered to be due to interaction between the geomagnetic field and the movement of charged particles comprising the ionosphere associated with the acoustic wave propagation. The model predicts that there will be no southward propagation of ionospheric disturbances caused by earthquakes in southern hemisphere mid-latitudes, which needs be confirmed by future earthquakes. The point (3) enabled the authors to define the empirical equation to calculate "Ionospheric disturbance magnitude" using the focal distance and disturbance amplitudes. Because the ionospheric disturbance monitoring does not require precise orbit information, such magnitudes could be determined near real time. This may help us, e.g. issue early warning message of Tsunami.
Regeneration concerns in areas impacted by sudden oak death
Douglas D. McCreary
2005-01-01
Sudden Oak Death (SOD) is a new disease affecting several oak (Quercus spp.) species in California. It is caused by Phytophthora ramorum, a fungus-like water mold that causes bark cankers that girdles and kills mature trees.
Ahmad, Tariq; Fiuzat, Mona; Neely, Ben; Neely, Megan; Pencina, Michael J.; Kraus, William E.; Zannad, Faiez; Whellan, David J.; Donahue, Mark; Piña, Ileana L.; Adams, Kirkwood; Kitzman, Dalane W.; O’Connor, Christopher M.; Felker, G. Michael
2014-01-01
Objective To determine whether biomarkers of myocardial stress and fibrosis improve prediction of mode of death in patients with chronic heart failure. Background The two most common modes of death in patients with chronic heart failure are pump failure and sudden cardiac death. Prediction of mode of death may facilitate treatment decisions. The relationship between NT-proBNP, galectin-3, and ST2, biomarkers that reflect different pathogenic pathways in heart failure (myocardial stress and fibrosis), and mode of death is unknown. Methods HF-ACTION was a randomized controlled trial of exercise training vs. usual care in patients with chronic heart failure due to left ventricular systolic dysfunction (LVEF<35%). An independent clinical events committee prospectively adjudicated mode of death. NT-proBNP, galectin-3, and ST2 levels were assessed at baseline in 813 subjects. Associations between biomarkers and mode of death were assessed using cause-specific Cox-proportional hazards modeling, and interaction testing was used to measure differential association between biomarkers and pump failure versus sudden cardiac death. Discrimination and risk reclassification metrics were used to assess the added value of galectin-3 and ST2 in predicting mode of death risk beyond a clinical model that included NT-proBNP. Results After a median follow up of 2.5 years, there were 155 deaths: 49 from pump failure 42 from sudden cardiac death, and 64 from other causes. Elevations in all biomarkers were associated with increased risk of both pump failure and sudden cardiac death in both adjusted and unadjusted analyses. In each case, increases in the biomarker had a stronger association with pump failure than sudden cardiac death but this relationship was attenuated after adjustment for clinical risk factors. Clinical variables along with NT-proBNP levels were stronger predictors of pump failure (C statistic: 0.87) than sudden cardiac death (C statistic: 0.73). Addition of ST2 and galectin-3 led to improved net risk classification of 11% for sudden cardiac death, but not pump failure. Conclusions Clinical predictors along with NT-proBNP levels were strong predictors of pump failure risk, with insignificant incremental contributions of ST2 and galectin-3. Predictability of sudden cardiac death risk was less robust and enhanced by information provided by novel biomarkers. PMID:24952693
Constraining Future Sea Level Rise Estimates from the Amundsen Sea Embayment, West Antarctica
NASA Astrophysics Data System (ADS)
Nias, I.; Cornford, S. L.; Edwards, T.; Gourmelen, N.; Payne, A. J.
2016-12-01
The Amundsen Sea Embayment (ASE) is the primary source of mass loss from the West Antarctic Ice Sheet. The catchment is particularly susceptible to grounding line retreat, because the ice sheet is grounded on bedrock that is below sea level and deepening towards its interior. Mass loss from the ASE ice streams, which include Pine Island, Thwaites and Smith glaciers, is a major uncertainty on future sea level rise, and understanding the dynamics of these ice streams is essential to constraining this uncertainty. The aim of this study is to construct a distribution of future ASE sea level contributions from an ensemble of ice sheet model simulations and observations of surface elevation change. A 284 member ensemble was performed using BISICLES, a vertically-integrated ice flow model with adaptive mesh refinement. Within the ensemble parameters associated with basal traction, ice rheology and sub-shelf melt rate were perturbed, and the effect of bed topography and sliding law were also investigated. Initially each configuration was run to 50 model years. Satellite observations of surface height change were then used within a Bayesian framework to assign likelihoods to each ensemble member. Simulations that better reproduced the current thinning patterns across the catchment were given a higher score. The resulting posterior distribution of sea level contributions is narrower than the prior distribution, although the central estimates of sea level rise are similar between the prior and posterior. The most extreme simulations were eliminated and the remaining ensemble members were extended to 200 years, using a simple melt rate forcing.
Future Cosmological Constraints From Fast Radio Bursts
NASA Astrophysics Data System (ADS)
Walters, Anthony; Weltman, Amanda; Gaensler, B. M.; Ma, Yin-Zhe; Witzemann, Amadeus
2018-03-01
We consider the possible observation of fast radio bursts (FRBs) with planned future radio telescopes, and investigate how well the dispersions and redshifts of these signals might constrain cosmological parameters. We construct mock catalogs of FRB dispersion measure (DM) data and employ Markov Chain Monte Carlo analysis, with which we forecast and compare with existing constraints in the flat ΛCDM model, as well as some popular extensions that include dark energy equation of state and curvature parameters. We find that the scatter in DM observations caused by inhomogeneities in the intergalactic medium (IGM) poses a big challenge to the utility of FRBs as a cosmic probe. Only in the most optimistic case, with a high number of events and low IGM variance, do FRBs aid in improving current constraints. In particular, when FRBs are combined with CMB+BAO+SNe+H 0 data, we find the biggest improvement comes in the {{{Ω }}}{{b}}{h}2 constraint. Also, we find that the dark energy equation of state is poorly constrained, while the constraint on the curvature parameter, Ω k , shows some improvement when combined with current constraints. When FRBs are combined with future baryon acoustic oscillation (BAO) data from 21 cm Intensity Mapping, we find little improvement over the constraints from BAOs alone. However, the inclusion of FRBs introduces an additional parameter constraint, {{{Ω }}}{{b}}{h}2, which turns out to be comparable to existing constraints. This suggests that FRBs provide valuable information about the cosmological baryon density in the intermediate redshift universe, independent of high-redshift CMB data.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taddei, Laura; Amendola, Luca, E-mail: laura.taddei@fis.unipr.it, E-mail: l.amendola@thphys.uni-heidelberg.de
Most cosmological constraints on modified gravity are obtained assuming that the cosmic evolution was standard ΛCDM in the past and that the present matter density and power spectrum normalization are the same as in a ΛCDM model. Here we examine how the constraints change when these assumptions are lifted. We focus in particular on the parameter Y (also called G{sub eff}) that quantifies the deviation from the Poisson equation. This parameter can be estimated by comparing with the model-independent growth rate quantity fσ{sub 8}(z) obtained through redshift distortions. We reduce the model dependency in evaluating Y by marginalizing over σ{submore » 8} and over the initial conditions, and by absorbing the degenerate parameter Ω{sub m,0} into Y. We use all currently available values of fσ{sub 8}(z). We find that the combination Y-circumflex =YΩ{sub m,0}, assumed constant in the observed redshift range, can be constrained only very weakly by current data, Y-circumflex =0.28{sub −0.23}{sup +0.35} at 68% c.l. We also forecast the precision of a future estimation of Y-circumflex in a Euclid-like redshift survey. We find that the future constraints will reduce substantially the uncertainty, Y-circumflex =0.30{sub −0.09}{sup +0.08} , at 68% c.l., but the relative error on Y-circumflex around the fiducial remains quite high, of the order of 30%. The main reason for these weak constraints is that Y-circumflex is strongly degenerate with the initial conditions, so that large or small values of Y-circumflex are compensated by choosing non-standard initial values of the derivative of the matter density contrast. Finally, we produce a forecast of a cosmological exclusion plot on the Yukawa strength and range parameters, which complements similar plots on laboratory scales but explores scales and epochs reachable only with large-scale galaxy surveys. We find that future data can constrain the Yukawa strength to within 3% of the Newtonian one if the range is around a few Megaparsecs. In the particular case of f(R) models, we find that the Yukawa range will be constrained to be larger than 80 Mpc/h or smaller than 2 Mpc/h (95% c.l.), regardless of the specific f(R) model.« less
A sudden end-Permian mass extinction (Invited)
NASA Astrophysics Data System (ADS)
Shen, S.
2013-12-01
The end-Permian mass extinction is the largest of the Phanerozoic. In the immediate aftermath the marine ecosystem was dominated by microbial and communities with disaster taxa. Plausible kill mechanism includes an extremely rapid, explosive release of gases such as carbon dioxide, methane and hydrogen sulfide. Siberian flood volcanism has been suggested as the most possible mechanism to trigger the massive release of greenhouse gases from volcanic eruptions and interaction of magmas with carbon from thick organic-rich deposits or rapid venting of coal-derived methane or massive combustion of coal. A sharp δ13C isotopic excursion, rapid disappearance of carbonate benthic communities and δ18O data from conodont apatite suggest rapid global warming. The end-Permian mass extinction occurred in less than 200,000 years. This extinction interval is constrained by two ash beds (Beds 25 and 28) at the Meishan section. However, the extinction patterns remain controversial largely due to the condensed nature of the Meishan sections. Geochemical signals and their interpretations are also contentious. Thus, the level of achievable stratigraphic resolution becomes crucial to determine the nature of the event and a detailed study of the extinction interval is essential to unravel the extinction pattern, chemostratigraphy, and the causes. However, the extinction interval at Meishan is only 26 cm thick and contains distinct gaps at the Permian-Triassic boundary (PTB) and possibly the base of Bed 25. Thus, it is impossible to resolve a detailed extinction pattern. Studying expanded sections is crucial to understand the detailed events before, during and after the main extinction. In this report, we show a highly-expanded Permian-Triassic boundary section in Guangxi Province, South China. The last 4.5 m between beds 22 and 28 of the Meishan sections is represented by a sequence of ~560 m at the section and the extinction interval between beds 24e and 28 at Meishan is represented by an interval about ~95 m which contains abundant benthic fossils. This expanded section reveals a very sudden extinction in a transgressive sequence that is inferred to have occurred within a few thousands of years.
López-Hoffman, Laura; Breshears, David D.; Allen, Craig D.; Miller, Marc L.
2013-01-01
Under a changing climate, devising strategies to help stakeholders adapt to alterations to ecosystems and their services is of utmost importance. In western North America, diminished snowpack and river flows are causing relatively gradual, homogeneous (system-wide) changes in ecosystems and services. In addition, increased climate variability is also accelerating the incidence of abrupt and patchy disturbances such as fires, floods and droughts. This paper posits that two key variables often considered in landscape ecology—the rate of change and the degree of patchiness of change—can aid in developing climate change adaptation strategies. We use two examples from the “borderland” region of the southwestern United States and northwestern Mexico. In piñon-juniper woodland die-offs that occurred in the southwestern United States during the 2000s, ecosystem services suddenly crashed in some parts of the system while remaining unaffected in other locations. The precise timing and location of die-offs was uncertain. On the other hand, slower, homogeneous change, such as the expected declines in water supply to the Colorado River delta, will likely impact the entire ecosystem, with ecosystem services everywhere in the delta subject to alteration, and all users likely exposed. The rapidity and spatial heterogeneity of faster, patchy climate change exemplified by tree die-off suggests that decision-makers and local stakeholders would be wise to operate under a Rawlsian “veil of ignorance,” and implement adaptation strategies that allow ecosystem service users to equitably share the risk of sudden loss of ecosystem services before actual ecosystem changes occur. On the other hand, in the case of slower, homogeneous, system-wide impacts to ecosystem services as exemplified by the Colorado River delta, adaptation strategies can be implemented after the changes begin, but will require a fundamental rethinking of how ecosystems and services are used and valued. In sum, understanding how the rate of change and degree of patchiness of change will constrain adaptive options is a critical consideration in preparing for climate change.
NASA Astrophysics Data System (ADS)
Wang, Y.; Stek, P. C.; Su, H.; Jiang, J. H.; Livesey, N. J.; Santee, M. L.
2014-12-01
Over the past century, global average surface temperature has warmed by about 0.16°C/decade, largely due to anthropogenic increases in well-mixed greenhouse gases. However, the trend in global surface temperatures has been nearly flat since 2000, raising a question regarding the exploration of the drivers of climate change. Water vapor is a strong greenhouse gas in the atmosphere. Previous studies suggested that the sudden decrease of stratospheric water vapor (SWV) around 2000 may have contributed to the stall of global warming. Since 2004, the SWV observed by Microwave Limb Sounder (MLS) on Aura satellite has shown a slow recovery. The role of recent SWV variations in global warming has not been quantified. We employ a coupled atmosphere-ocean climate model, the NCAR CESM, to address this issue. It is found that the CESM underestimates the stratospheric water vapor by about 1 ppmv due to limited representations of the stratospheric dynamic and chemical processes important for water vapor variabilities. By nudging the modeled SWV to the MLS observation, we find that increasing SWV by 1 ppmv produces a robust surface warming about 0.2°C in global-mean when the model reaches equilibrium. Conversely, the sudden drop of SWV from 2000 to 2004 would cause a surface cooling about -0.08°C in global-mean. On the other hand, imposing the observed linear trend of SWV based on the 10-year observation of MLS in the CESM yields a rather slow surface warming, about 0.04°C/decade. Our model experiments suggest that SWV contributes positively to the global surface temperature variation, although it may not be the dominant factor that drives the recent global warming hiatus. Additional sensitivity experiments show that the impact of SWV on surface climate is mostly governed by the SWV amount at 100 hPa in the tropics. Furthermore, the atmospheric model simulations driven by observed sea surface temperature (SST) show that the inter-annual variation of SWV follows that of SST, suggesting a close coupling between surface temperature and SWV.
Risk Factors in the Initial Presentation of Specific Cardiovascular Disease Syndromes
2013-03-03
Heart Diseases; Cardiovascular Diseases; Acute Myocardial Infarction; Unstable Angina; Chronic Stable Angina; Ischemic Stroke; Cerebrovascular Accident; Subarachnoid Hemorrhage; Transient Ischemic Attack; Abdominal Aortic Aneurysm; Peripheral Arterial Disease; Sudden Coronary Death; Ventricular Arrhythmia; Sudden Death; Cardiac Arrest; Heart Failure
75 FR 1363 - Integrated System Power Rates
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-11
... service load immediately when disturbance conditions are experienced due to a sudden loss of generation or... conditions are experienced due to a sudden loss of generation or load. ``Supplemental Operating Reserve... Secretary has approved and placed into effect on an [[Page 1364
Heart Attack or Sudden Cardiac Arrest: How Are They Different?
... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Heart Attack or Sudden Cardiac Arrest: How Are They Different? ... and procedures related to heart disease and stroke. Heart Attack • Home • About Heart Attacks Acute Coronary Syndrome (ACS) ...
Quantum field theory of interacting dark matter and dark energy: Dark monodromies
D’Amico, Guido; Hamill, Teresa; Kaloper, Nemanja
2016-11-28
We discuss how to formulate a quantum field theory of dark energy interacting with dark matter. We show that the proposals based on the assumption that dark matter is made up of heavy particles with masses which are very sensitive to the value of dark energy are strongly constrained. Quintessence-generated long-range forces and radiative stability of the quintessence potential require that such dark matter and dark energy are completely decoupled. However, if dark energy and a fraction of dark matter are very light axions, they can have significant mixings which are radiatively stable and perfectly consistent with quantum field theory.more » Such models can naturally occur in multi-axion realizations of monodromies. The mixings yield interesting signatures which are observable and are within current cosmological limits but could be constrained further by future observations« less
NASA Astrophysics Data System (ADS)
Duan, Suqin Q.; Wright, Jonathon S.; Romps, David M.
2018-02-01
Atmospheric water-vapor isotopes have been proposed as a potentially powerful constraint on convection, which plays a critical role in Earth's present and future climate. It is shown here, however, that the mean tropical profile of HDO in the free troposphere does not usefully constrain the mean convective entrainment rate or precipitation efficiency. This is demonstrated using a single-column analytical model of atmospheric water isotopes. The model has three parameters: the entrainment rate, the precipitation efficiency, and the distance that evaporating condensates fall. At a given relative humidity, the possible range of HDO is small: its range is comparable to both the measurement uncertainty in the mean tropical profile and the structural uncertainty of a single-column model. Therefore, the mean tropical HDO profile is unlikely to add information about convective processes in a bulk-plume framework that cannot already be learned from relative humidity alone.
Probing primordial features with next-generation photometric and radio surveys
NASA Astrophysics Data System (ADS)
Ballardini, M.; Finelli, F.; Maartens, R.; Moscardini, L.
2018-04-01
We investigate the possibility of using future photometric and radio surveys to constrain the power spectrum of primordial fluctuations that is predicted by inflationary models with a violation of the slow-roll phase. We forecast constraints with a Fisher analysis on the amplitude of the parametrized features on ultra-large scales, in order to assess whether these could be distinguishable over the cosmic variance. We find that the next generation of photometric and radio surveys has the potential to test these models at a sensitivity better than current CMB experiments and that the synergy between galaxy and CMB observations is able to constrain models with many extra parameters. In particular, an SKA continuum survey with a huge sky coverage and a flux threshold of a few μJy could confirm the presence of a new phase in the early Universe at more than 3σ.
Shallow seismic imaging of folds above the Puente Hills blind-thrust fault, Los Angeles, California
Pratt, T.L.; Shaw, J.H.; Dolan, J.F.; Christofferson, S.A.; Williams, R.A.; Odum, J.K.; Plesch, A.
2002-01-01
High-resolution seismic reflection profiles image discrete folds in the shallow subsurface (<600 m) above two segments of the Puente Hills blind-thrust fault system, Los Angeles basin, California. The profiles demonstrate late Quaternary activity at the fault tip, precisely locate the axial surfaces of folds within the upper 100 m, and constrain the geometry and kinematics of recent folding. The Santa Fe Springs segment of the Puente Hills fault zone shows an upward-narrowing kink band with an active anticlinal axial surface, consistent with fault-bend folding above an active thrust ramp. The Coyote Hills segment shows an active synclinal axial surface that coincides with the base of a 9-m-high scarp, consistent with tip-line folding or the presence of a backthrust. The seismic profiles pinpoint targets for future geologic work to constrain slip rates and ages of past events on this important fault system.
Diagnostic Simulations of the Lunar Exosphere using Coma and Tail
NASA Astrophysics Data System (ADS)
Lee, Dong Wook; Kim, Sang J.
2017-10-01
The characteristics of the lunar exosphere can be constrained by comparing simulated models with observational data of the coma and tail (Lee et al., JGR, 2011); and thus far a few independent approaches on this issue have been performed and presented in the literature. Since there are two-different observational constraints for the lunar exosphere, it is interesting to find the best exospheric model that can account for the observed characteristics of the coma and tail. Considering various initial conditions of different sources and space weather, we present preliminary time-dependent simulations between the initial and final stages of the development of the lunar tail. Based on an updated 3-D model, we are planning to conduct numerous simulations to constrain the best model parameters from the coma images obtained from coronagraph observations supported by a NASA monitoring program (Morgan, Killen, and Potter, AGU, 2015) and future tail data.
NASA Astrophysics Data System (ADS)
Heinz, Sebastian
2017-09-01
When an X-ray transient exhibits a bright flare, scattering by interstellar dust clouds can give rise to a light echo in the form of concentric rings. To date, three such echoes have been detected, each leading to significant discoveries and press attention. We propose a Target-of-Opportunity campaign to observe future echoes with the aim to follow the temporal evolution of the echo in order to (a) map the 3D distribution interstellar dust along the line of sight to parsec accuracy, (b) constrain the composition and grain size distribution of ISM dust in each of the clouds towards the source, (c) measure the distance to the X-ray source, (d) constrain the velocity dispersion of molecular clouds and (e) search for evidence of streaming velocities by combing X-ray and CO data on the clouds.
ENVIRONMENTAL SCIENCE. Profiling risk and sustainability in coastal deltas of the world.
Tessler, Z D; Vörösmarty, C J; Grossberg, M; Gladkova, I; Aizenman, H; Syvitski, J P M; Foufoula-Georgiou, E
2015-08-07
Deltas are highly sensitive to increasing risks arising from local human activities, land subsidence, regional water management, global sea-level rise, and climate extremes. We quantified changing flood risk due to extreme events using an integrated set of global environmental, geophysical, and social indicators. Although risks are distributed across all levels of economic development, wealthy countries effectively limit their present-day threat by gross domestic product-enabled infrastructure and coastal defense investments. In an energy-constrained future, such protections will probably prove to be unsustainable, raising relative risks by four to eight times in the Mississippi and Rhine deltas and by one-and-a-half to four times in the Chao Phraya and Yangtze deltas. The current emphasis on short-term solutions for the world's deltas will greatly constrain options for designing sustainable solutions in the long term. Copyright © 2015, American Association for the Advancement of Science.
Constraints and tests of the OPERA superluminal neutrinos.
Bi, Xiao-Jun; Yin, Peng-Fei; Yu, Zhao-Huan; Yuan, Qiang
2011-12-09
The superluminal neutrinos detected by OPERA indicate Lorentz invariance violation (LIV) of the neutrino sector at the order of 10(-5). We study the implications of the result in this work. We find that such a large LIV implied by OPERA data will make the neutrino production process π → μ + ν(μ) kinematically forbidden for a neutrino energy greater than about 5 GeV. The OPERA detection of neutrinos at 40 GeV can constrain the LIV parameter to be smaller than 3×10(-7). Furthermore, the neutrino decay in the LIV framework will modify the neutrino spectrum greatly. The atmospheric neutrino spectrum measured by the IceCube Collaboration can constrain the LIV parameter to the level of 10(-12). The future detection of astrophysical neutrinos of galactic sources is expected to be able to give an even stronger constraint on the LIV parameter of neutrinos.
Constraints and Tests of the OPERA Superluminal Neutrinos
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bi Xiaojun; Yin Pengfei; Yu Zhaohuan
The superluminal neutrinos detected by OPERA indicate Lorentz invariance violation (LIV) of the neutrino sector at the order of 10{sup -5}. We study the implications of the result in this work. We find that such a large LIV implied by OPERA data will make the neutrino production process {pi}{yields}{mu}+{nu}{sub {mu}} kinematically forbidden for a neutrino energy greater than about 5 GeV. The OPERA detection of neutrinos at 40 GeV can constrain the LIV parameter to be smaller than 3x10{sup -7}. Furthermore, the neutrino decay in the LIV framework will modify the neutrino spectrum greatly. The atmospheric neutrino spectrum measured bymore » the IceCube Collaboration can constrain the LIV parameter to the level of 10{sup -12}. The future detection of astrophysical neutrinos of galactic sources is expected to be able to give an even stronger constraint on the LIV parameter of neutrinos.« less
Constraining the Deep Origin of Parasitic Flatworms and Host-Interactions with Fossil Evidence.
De Baets, Kenneth; Dentzien-Dias, Paula; Upeniece, Ieva; Verneau, Olivier; Donoghue, Philip C J
2015-01-01
Novel fossil discoveries have contributed to our understanding of the evolutionary appearance of parasitism in flatworms. Furthermore, genetic analyses with greater coverage have shifted our views on the coevolution of parasitic flatworms and their hosts. The putative record of parasitic flatworms is consistent with extant host associations and so can be used to put constraints on the evolutionary origin of the parasites themselves. The future lies in new molecular clock analyses combined with additional discoveries of exceptionally preserved flatworms associated with hosts and coprolites. Besides direct evidence, the host fossil record and biogeography have the potential to constrain their evolutionary history, albeit with caution needed to avoid circularity, and a need for calibrations to be implemented in the most conservative way. This might result in imprecise, but accurate divergence estimates for the evolution of parasitic flatworms. Copyright © 2015 Elsevier Ltd. All rights reserved.
Small but mighty: Dark matter substructures
NASA Astrophysics Data System (ADS)
Cyr-Racine, Francis-Yan; Keeton, Charles; Moustakas, Leonidas
2018-01-01
The fundamental properties of dark matter, such as its mass, self-interaction, and coupling to other particles, can have a major impact on the evolution of cosmological density fluctuations on small length scales. Strong gravitational lenses have long been recognized as powerful tools to study the dark matter distribution on these small subgalactic scales. In this talk, we discuss how gravitationally lensed quasars and extended lensed arcs could be used to probe non minimal dark matter models. We comment on the possibilities enabled by precise astrometry, deep imaging, and time delays to extract information about mass substructures inside lens galaxies. To this end, we introduce a new lensing statistics that allows for a robust diagnostic of the presence of perturbations caused by substructures. We determine which properties of mass substructures are most readily constrained by lensing data and forecast the constraining power of current and future observations.
Quantum field theory of interacting dark matter and dark energy: Dark monodromies
DOE Office of Scientific and Technical Information (OSTI.GOV)
D’Amico, Guido; Hamill, Teresa; Kaloper, Nemanja
We discuss how to formulate a quantum field theory of dark energy interacting with dark matter. We show that the proposals based on the assumption that dark matter is made up of heavy particles with masses which are very sensitive to the value of dark energy are strongly constrained. Quintessence-generated long-range forces and radiative stability of the quintessence potential require that such dark matter and dark energy are completely decoupled. However, if dark energy and a fraction of dark matter are very light axions, they can have significant mixings which are radiatively stable and perfectly consistent with quantum field theory.more » Such models can naturally occur in multi-axion realizations of monodromies. The mixings yield interesting signatures which are observable and are within current cosmological limits but could be constrained further by future observations« less
Shallow megathrust earthquake ruptures betrayed by their outer-trench aftershocks signature
NASA Astrophysics Data System (ADS)
Sladen, Anthony; Trevisan, Jenny
2018-02-01
For some megathrust earthquakes, the rupture extends to the solid Earth's surface, at the ocean floor. This unexpected behaviour holds strong implications for the tsunami potential of subduction zones and for the physical conditions governing earthquakes, but such ruptures occur in underwater areas which are hard to observe, even with current instrumentation and imaging techniques. Here, we evidence that aftershocks occurring ocean-ward from the trench are conditioned by near-surface rupture of the megathrust fault. Comparison to well constrained earthquake slip models further reveals that for each event the number of aftershocks is proportional to the amount of shallow slip, a link likely related to static stress transfer. Hence, the spatial distribution of these specific aftershock sequences could provide independent constrains on the coseismic shallow slip of future events. It also offers the prospect to be able to reassess the rupture of many large subduction earthquakes back to the beginning of the instrumental era.
[Research Progress of Sudden Cardiac Death in Forensic Medicine].
Zheng, D; Yin, K; Zheng, J J; Zhou, N; Liu, Y; Fu, X; Cheng, J D
2017-10-01
Sudden death (SD) is a special kind of death owing to disease, which severely threatening the lives of community population. As the most common type of SD, sudden cardiac death (SCD) has always been a crucial content of identification and research in forensic pathology. This article reviews the research progress from the aspects of epidemiology, morphology, molecular pathology and virtual anatomy of SCD in forensic medicine, so as to provide a reference for the morphological identification, determination of cause of death, and integrated control of this kind of SD. Copyright© by the Editorial Department of Journal of Forensic Medicine.