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  1. Surviving Critical Illness: The Acute Respiratory Distress Syndrome as Experienced by Patients and Their Caregivers

    PubMed Central

    Cox, Christopher E.; Docherty, Sharron L.; Brandon, Debra H.; Whaley, Christie; Attix, Deborah K.; Clay, Alison S.; Dore, Daniel V.; Hough, Catherine L.; White, Douglas B.; Tulsky, James A.

    2009-01-01

    Objective Survivors of the acute respiratory distress syndrome (ARDS), a systemic critical illness, often report poor quality of life based on responses to standardized questionnaires. However, the experiences of ARDS survivors have not been reported. Our objective was to characterize the effects of critical illness in the daily lives and functioning of ARDS survivors. Design, Setting, and Patients We recruited consecutively 31 ARDS survivors and their informal caregivers from medical and surgical intensive care units of an academic medical center and a community hospital. Eight patients died before completing interviews. We conducted semi-structured interviews with 23 ARDS survivors and 24 caregivers three to nine months after ICU admission, stopping enrollment after thematic saturation was reached. Transcripts were analyzed using Colaizzi’s qualitative methodology to identify significant ways in which survivors’ critical illness experience impacted their lives. Measurements and Main Results Participants related five key elements of experience as survivors of ARDS: pervasive memories of critical care, day to day impact of new disability, critical illness defining the sense of self, relationship strain and change, and ability to cope with disability. Survivors described remarkable disability that persisted for months. Caregivers’ interviews revealed substantial strain from caregiving responsibilities, as well as frequent symptom minimization by patients. Conclusions The diverse and unique experiences of ARDS survivors reflect the global impact of severe critical illness. We have identified symptom domains important to ARDS patients that are not well represented in existing health outcomes measures. These insights may aid the development of targeted interventions to enhance recovery and return of function after ARDS. PMID:19865004

  2. Enteral feeding in the critically ill: the role of the gastroenterologist.

    PubMed

    Fang, John C; Delegge, Mark H

    2011-06-01

    Expertise in enteral nutrition (EN) is an important aspect of the skill set of the clinical gastroenterologist. Delivery of adequate EN in critically ill patients is an active therapy that attenuates the metabolic response to stress and favorably modulates the immune system. EN is less expensive than parenteral nutrition and is favored in most cases because of improvement in patient outcomes, including infections and length of stay. Newer endoscopic techniques for placing nasoenteric feeding tubes have been developed, which improve placement success and efficiency. It appears that there is an ideal window period of 24-48 h when enteral feeding should be started in critically ill patients. Most patients can be fed into the stomach, but certain groups may benefit from small bowel feeding. Protocols on how to start and monitor enteral feeding have been developed. Immune-modulating feeding formulations also appear to be beneficial in specific patient populations. The gastroenterologist is a crucial member of the multidisciplinary team for nutritional support in the intensive care unit patient, with his knowledge of gastrointestinal pathophysiology, nutrition, and endoscopic feeding-tube placement. PMID:21468014

  3. Continuous-time adaptive critics.

    PubMed

    Hanselmann, Thomas; Noakes, Lyle; Zaknich, Anthony

    2007-05-01

    A continuous-time formulation of an adaptive critic design (ACD) is investigated. Connections to the discrete case are made, where backpropagation through time (BPTT) and real-time recurrent learning (RTRL) are prevalent. Practical benefits are that this framework fits in well with plant descriptions given by differential equations and that any standard integration routine with adaptive step-size does an adaptive sampling for free. A second-order actor adaptation using Newton's method is established for fast actor convergence for a general plant and critic. Also, a fast critic update for concurrent actor-critic training is introduced to immediately apply necessary adjustments of critic parameters induced by actor updates to keep the Bellman optimality correct to first-order approximation after actor changes. Thus, critic and actor updates may be performed at the same time until some substantial error build up in the Bellman optimality or temporal difference equation, when a traditional critic training needs to be performed and then another interval of concurrent actor-critic training may resume. PMID:17526332

  4. Time-Critical Volume Rendering

    NASA Technical Reports Server (NTRS)

    Kaufman, Arie

    1998-01-01

    For the past twelve months, we have conducted and completed a joint research entitled "Time- Critical Volume Rendering" with NASA Ames. As expected, High performance volume rendering algorithms have been developed by exploring some new faster rendering techniques, including object presence acceleration, parallel processing, and hierarchical level-of-detail representation. Using our new techniques, initial experiments have achieved real-time rendering rates of more than 10 frames per second of various 3D data sets with highest resolution. A couple of joint papers and technique reports as well as an interactive real-time demo have been compiled as the result of this project.

  5. Continuous infusion of antibiotics in the critically ill: The new holy grail for beta-lactams and vancomycin?

    PubMed Central

    2012-01-01

    The alarming global rise of antimicrobial resistance combined with the lack of new antimicrobial agents has led to a renewed interest in optimization of our current antibiotics. Continuous infusion (CI) of time-dependent antibiotics has certain theoretical advantages toward efficacy based on pharmacokinetic/pharmacodynamic principles. We reviewed the available clinical studies concerning continuous infusion of beta-lactam antibiotics and vancomycin in critically ill patients. We conclude that CI of beta-lactam antibiotics is not necessarily more advantageous for all patients. Continuous infusion is only likely to have clinical benefits in subpopulations of patients where intermittent infusion is unable to achieve an adequate time above the minimal inhibitory concentration (T > MIC). For example, in patients with infections caused by organisms with elevated MICs, patients with altered pharmacokinetics (such as the critically ill) and possibly also immunocompromised patients. For vancomycin CI can be chosen, not always for better clinical efficacy, but because it is practical, cheaper, associated with less AUC24h (area under the curve >24 h)-variability, and easier to monitor. PMID:22747633

  6. Erik Erikson: critical times, critical theory.

    PubMed

    Douvan, E

    1997-01-01

    The work and legacy of Erik Erikson are described in this brief outline of his career, his theories, and his impact on psychoanalysis, psychology, history, and the broader culture. His conception of the adolescent task-weaving internal tastes, talents, and values together with elements of one's life history and the demands of one's culture into a coherent identity-has had profound effects on developmental psychology and the way in which sophisticated youth construct and describe their lives. His extension of development through adulthood and old age established the field of life course development. His emphasis on the impact of history and culture on development was a critical element in the developing field of ego psychology. Many of his major contributions can be fruitfully understood in the context of his personal history and individual qualities. PMID:9256525

  7. Stimulated Whole Blood Cytokine Release as a Biomarker of Immunosuppression in the Critically Ill: The Need for a Standardized Methodology

    PubMed Central

    Segre, Elisabetta; Fullerton, James N.

    2016-01-01

    ABSTRACT Objective: Reduced ex vivo lipopolysaccharide (LPS) stimulated whole blood pro-inflammatory cytokine release is a hallmark of immunosuppression in the critically ill and predicts adverse clinical outcomes. No standard technique for performing the assay currently exists. The impact of methodological heterogeneity was determined. Design, Setting, Subjects, and Interventions: Clinical experimental study set in a research laboratory. Venous blood from 5 to 10 healthy volunteers/experiment (total participant group: 18 subjects, 72% men, mean age 32) was stimulated ex vivo to evaluate the effect of variables identified via literature review on tumor necrosis factor-α (TNFα) release. These included sample handling, stimulation technique, and incubation conditions. Reporting convention was additionally assessed. Main Results: Measured TNFα release was significantly altered by source of LPS, concentration of LPS employed, duration and temperature of incubation prior to supernatant aspiration, and predilution of blood (repeated measures ANOVA, all P < 0.01). Sample handling prior to stimulation (anticoagulant employed, time to LPS addition, and storage temperature) also caused significant alterations in TNFα release. Considerable interindividual variation was observed (range 1,024–4,649 pg/mL, mean 2,339 pg/mL). Normalization by monocyte count and pretreatment with a cyclooxygenase inhibitor (indomethacin 10 μM) reduced the coefficient of variation from 47.17% to 32.09%. Conclusions: Inconsistency in interlaboratory methodology and reporting impairs interpretation, comparability, and reproducibility of the ex vivo LPS-stimulated whole blood cytokine release assay. A standardized validated technique is required. The advent of trials of immunoadjuvant agents renders this a clinical imperative. PMID:27089173

  8. Can we protect the gut in critical illness? The role of growth factors and other novel approaches.

    PubMed

    Dominguez, Jessica A; Coopersmith, Craig M

    2010-07-01

    The intestine plays a central role in the pathophysiology of critical illness and is frequently called the "motor" of the systemic inflammatory response. Perturbations to the intestinal barrier can lead to distant organ damage and multiple organ failure. Therefore, identifying ways to preserve intestinal integrity may be of paramount importance. Growth factors and other peptides have emerged as potential tools for modulation of intestinal inflammation and repair due to their roles in cellular proliferation, differentiation, migration, and survival. This review examines the involvement of growth factors and other peptides in intestinal epithelial repair during critical illness and their potential use as therapeutic targets. PMID:20643306

  9. Can We Protect the Gut in Critical Illness: The Role of Growth Factors and Other Novel Approaches

    PubMed Central

    Dominguez, Jessica A.; Coopersmith, Craig M.

    2010-01-01

    Synopsis The intestine plays a central role in the pathophysiology of critical illness and is frequently called the “motor” of the systemic inflammatory response. Perturbations to the intestinal barrier can lead to distant organ damage and multiple organ failure. Therefore, identifying ways to preserve intestinal integrity may be of paramount importance. Growth factors and other peptides have emerged as potential tools for modulation of intestinal inflammation and repair due to their roles in cellular proliferation, differentiation, migration, and survival. In this review, we will examine the involvement of growth factors and other peptides in intestinal epithelial repair during critical illness and their potential use as therapeutic targets. PMID:20643306

  10. Bridging Fields at a Critical Time

    ERIC Educational Resources Information Center

    Baggaley, Jon

    2014-01-01

    The launch of the "Journal of Learning for Development" occurs at a critical time for the education and development field. The "massive open online course" concept currently being implemented by Western educators is considered as a potential cost-saver in developing nations also. MOOCs based on reliable pedagogical principles…

  11. Critical time for NSF, NASA funding bills

    NASA Astrophysics Data System (ADS)

    Jones, Richard

    Although the new fiscal year does not start until October, the next few weeks will be critical in determining the amount of money which the National Science Foundation and the National Aeronautics and Space Administration receive. Scientists who want to communicate their views to key representatives and senators about these agencies should do so now.Every year Congress must pass new funding, or appropriations, legislation. Both NSF and NASA funding come under the jurisdiction of the House and Senate appropriations subcommittees for the Veterans Administration, Department of Housing and Urban Development, and Independent Agencies. These two subcommittees have already heard from NSF officials, and will wrap-up official NASA testimony this week. Several days of hearings from public witnesses are also scheduled.

  12. Critical time scale of coarse-graining entropy production

    NASA Astrophysics Data System (ADS)

    Sohn, Jang-il

    2016-04-01

    We study coarse-grained entropy production in an asymmetric random walk system on a periodic one-dimensional lattice. In coarse-grained systems, the original dynamics are unavoidably destroyed, but the coarse-grained entropy production is not hidden below the critical time-scale separation. The hidden entropy production is rapidly increasing near the critical time-scale separation.

  13. Time Critical Isosurface Refinement and Smoothing

    SciTech Connect

    Pascucci, V.; Bajaj, C.L.

    2000-07-10

    Multi-resolution data-structures and algorithms are key in Visualization to achieve real-time interaction with large data-sets. Research has been primarily focused on the off-line construction of such representations mostly using decimation schemes. Drawbacks of this class of approaches include: (i) the inability to maintain interactivity when the displayed surface changes frequently, (ii) inability to control the global geometry of the embedding (no self-intersections) of any approximated level of detail of the output surface. In this paper we introduce a technique for on-line construction and smoothing of progressive isosurfaces. Our hybrid approach combines the flexibility of a progressive multi-resolution representation with the advantages of a recursive sub-division scheme. Our main contributions are: (i) a progressive algorithm that builds a multi-resolution surface by successive refinements so that a coarse representation of the output is generated as soon as a coarse representation of the input is provided, (ii) application of the same scheme to smooth the surface by means of a 3D recursive subdivision rule, (iii) a multi-resolution representation where any adaptively selected level of detail surface is guaranteed to be free of self-intersections.

  14. The Hobart Time Ball and Time Gun: a Critical Review

    NASA Astrophysics Data System (ADS)

    Kinns, Roger

    2011-07-01

    Discussion at the Royal Society in Hobart in 1865 and acoustic experiments in 1868 led to a combined time ball and time gun service in Hobart from March 1875. Complaints from residents led to relocation of the gun a month later, but it was then fired from Queen's Battery in the Domain for half a century. The drop of the ball at Battery Point was always the master signal; the gun was fired when the ball was seen to drop. During the early years, private citizens in Hobart provided the time reference. From September 1886, an electric telegraph signal from Hobart Observatory was used to provide correct time to the ball operator, but signals were of questionable accuracy. During February 1910, the source of the telegraph signal was changed from Hobart Observatory to Melbourne Observatory, but the service was still unreliable and there was pressure to re-equip Hobart Observatory. Finally, automatic dropping of the time ball by telegraph from Melbourne was introduced in November 1910. The time ball service ended in February 1927. The time gun had probably ceased to operate by the end of 1923, but before that date there were sometimes long gaps in the time gun service, particularly on Sundays.

  15. Critical Media Literacy: Research, Theory, and Practice in "New Times."

    ERIC Educational Resources Information Center

    Alvermann, Donna E.; Hagood, Margaret C.

    2000-01-01

    Reviews literature on critical media literacy, producing a framework for exploring its implications for educators teaching literacy skills in "New Times." The article examines work on critical theory, popular culture, and mass media in various fields, arguing that the present discourse of schooling is unable to support the incorporation of…

  16. Time and Performance on the California Critical Thinking Skills Test.

    ERIC Educational Resources Information Center

    Frisby, Craig L.; Traffanstedt, Bobby K.

    2003-01-01

    Investigates the relationship between total scores on the California Critical Thinking Skills Test (CCTST) and the time taken to complete it. Finds that slower test takers obtained significantly higher scores. Discusses implications of these findings for college instruction. (SG)

  17. Time discounting and time preference in animals: A critical review.

    PubMed

    Hayden, Benjamin Y

    2016-02-01

    Animals are an important model for studies of impulsivity and self-control. Many studies have made use of the intertemporal choice task, which pits small rewards available sooner against larger rewards available later (typically several seconds), repeated over many trials. Preference for the sooner reward is often taken to indicate impulsivity and/or a failure of self-control. This review shows that very little evidence supports this assumption; on the contrary, ostensible discounting behavior may reflect a boundedly rational but not necessarily impulsive reward-maximizing strategy. Specifically, animals may discount weakly, or even adopt a long-term rate-maximizing strategy, but fail to fully incorporate postreward delays into their choices. This failure may reflect learning biases. Consequently, tasks that measure animal discounting may greatly overestimate the true discounting and may be confounded by processes unrelated to time preferences. If so, animals may be much more patient than is widely believed; human and animal intertemporal choices may reflect unrelated mental operations; and the shared hyperbolic shape of the human and animal discount curves, which is used to justify cross-species comparisons, may be coincidental. The discussion concludes with a consideration of alternative ways to measure self-control in animals. PMID:26063653

  18. Identifying the critical climatic time window that affects trait expression.

    PubMed

    van de Pol, Martijn; Cockburn, Andrew

    2011-05-01

    Identifying the critical time window during which climatic drivers affect the expression of phenological, behavioral, and demographic traits is crucial for predicting the impact of climate change on trait and population dynamics. Two widely used associative methods exist to identify critical climatic periods: sliding-window models and recursive operators in which the memory of past weather fades over time. Both approaches have different strong points, which we combine here into a single method. Our method uses flexible functions to differentially weight past weather, which can reflect competing hypotheses about time lags and the relative importance of recent and past weather for trait expression. Using a 22-year data set, we illustrate that the climatic window identified by our new method explains more of the phenological variation in a sexually selected trait than existing approaches. Our new method thus helps to better identify the critical time window and the causes of trait response to environmental variability. PMID:21508615

  19. Scheduling time-critical graphics on multiple processors

    NASA Technical Reports Server (NTRS)

    Meyer, Tom W.; Hughes, John F.

    1995-01-01

    This paper describes an algorithm for the scheduling of time-critical rendering and computation tasks on single- and multiple-processor architectures, with minimal pipelining. It was developed to manage scientific visualization scenes consisting of hundreds of objects, each of which can be computed and displayed at thousands of possible resolution levels. The algorithm generates the time-critical schedule using progressive-refinement techniques; it always returns a feasible schedule and, when allowed to run to completion, produces a near-optimal schedule which takes advantage of almost the entire multiple-processor system.

  20. Critical Literacy Can Help in These Troubled Times.

    ERIC Educational Resources Information Center

    Sisk, Dorothy

    2002-01-01

    This article discusses how critical literacy can offer gifted students a way to research great leaders and their actions in times of crisis, enabling them to project the type of leadership that is called for in today's world. Reading activities, writing activities, and oral language activities are described. (Contains 1 reference.) (CR)

  1. Time-critical multirate scheduling using contemporary real-time operating system services

    NASA Technical Reports Server (NTRS)

    Eckhardt, D. E., Jr.

    1983-01-01

    Although real-time operating systems provide many of the task control services necessary to process time-critical applications (i.e., applications with fixed, invariant deadlines), it may still be necessary to provide a scheduling algorithm at a level above the operating system in order to coordinate a set of synchronized, time-critical tasks executing at different cyclic rates. The scheduling requirements for such applications and develops scheduling algorithms using services provided by contemporary real-time operating systems.

  2. Critical Timing without a Timer for Embryonic Development.

    PubMed

    Tufcea, Daniel E; François, Paul

    2015-10-20

    Timing of embryonic development is precisely controlled, but the mechanisms underlying biological timers are still unclear. Here, a validated model for timing under control of Sonic Hedgehog is revisited and generalized to an arbitrary number of genes. The developmental dynamics where a temporal sequence of gene expression recapitulates a steady-state spatial pattern can be realized through a simple network close to criticality, controlled by the duration of exposure to a morphogen. Criticality simultaneously accounts for many observed biological properties, such as timing, multistability, and canalization of genetic expression. This process can be parsimoniously generalized in many dimensions with a minimum number of genes, all repressing each other with asymmetrical strengths, which also explains sequential activation of different fates. Separation of timescales allows for a simple analytical interpretation. Finally, it is shown that even in the presence of noise, coupling between cells preserves criticality and robust patterning. The model offers a simple theoretical framework for the study of emergent developmental timers. PMID:26488664

  3. Exploring Gigabyte Datasets in Real Time: Architectures, Interfaces and Time-Critical Design

    NASA Technical Reports Server (NTRS)

    Bryson, Steve; Gerald-Yamasaki, Michael (Technical Monitor)

    1998-01-01

    Architectures and Interfaces: The implications of real-time interaction on software architecture design: decoupling of interaction/graphics and computation into asynchronous processes. The performance requirements of graphics and computation for interaction. Time management in such an architecture. Examples of how visualization algorithms must be modified for high performance. Brief survey of interaction techniques and design, including direct manipulation and manipulation via widgets. talk discusses how human factors considerations drove the design and implementation of the virtual wind tunnel. Time-Critical Design: A survey of time-critical techniques for both computation and rendering. Emphasis on the assignment of a time budget to both the overall visualization environment and to each individual visualization technique in the environment. The estimation of the benefit and cost of an individual technique. Examples of the modification of visualization algorithms to allow time-critical control.

  4. Evaluating the propagation effects of time critical targeting

    NASA Astrophysics Data System (ADS)

    McQueary, Bruce R.; Krause, Lee; Ferens, Daniel V.

    2005-05-01

    As General John P. Jumper, Air Force Chief of Staff, noted the bulk of an Air Operations Center Air Tasking Order cycle is spent gathering information from different stovepipe intelligence assets, then manually evaluating the results and planning implications. This time consuming process is an obstacle that inhibits the real-time battlespace awareness needed by commanders to dynamically task assets to address time critical targets and help the Air Force meet its goal of "striking mobile and emerging targets in single digit minutes". This paper describes how research performed for the Dynamic Intelligence Anticipation, Prioritization, and Exploitation System (DIAPES) supports this goal by leveraging advances in ontological modeling, intelligence data integration; artificial intelligence; and visualization. DIAPES applies automated analysis and visualization to an integrated ontology that specifies the relationships among intelligence and planning products and battlespace execution assets. This research seeks to enable commanders and analysts to perform 'what-if' scenarios to judge tradeoffs and determine the potential propagation effects that retasking assets to address time critical targets have throughout battlespace plans and participants.

  5. Critical time scales for advection-diffusion-reaction processes

    NASA Astrophysics Data System (ADS)

    Ellery, Adam J.; Simpson, Matthew J.; McCue, Scott W.; Baker, Ruth E.

    2012-04-01

    The concept of local accumulation time (LAT) was introduced by Berezhkovskii and co-workers to give a finite measure of the time required for the transient solution of a reaction-diffusion equation to approach the steady-state solution [A. M. Berezhkovskii, C. Sample, and S. Y. Shvartsman, Biophys. J.BIOJAU0006-349510.1016/j.bpj.2010.07.045 99, L59 (2010); A. M. Berezhkovskii, C. Sample, and S. Y. Shvartsman, Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.83.051906 83, 051906 (2011)]. Such a measure is referred to as a critical time. Here, we show that LAT is, in fact, identical to the concept of mean action time (MAT) that was first introduced by McNabb [A. McNabb and G. C. Wake, IMA J. Appl. Math.IJAMDM0272-496010.1093/imamat/47.2.193 47, 193 (1991)]. Although McNabb's initial argument was motivated by considering the mean particle lifetime (MPLT) for a linear death process, he applied the ideas to study diffusion. We extend the work of these authors by deriving expressions for the MAT for a general one-dimensional linear advection-diffusion-reaction problem. Using a combination of continuum and discrete approaches, we show that MAT and MPLT are equivalent for certain uniform-to-uniform transitions; these results provide a practical interpretation for MAT by directly linking the stochastic microscopic processes to a meaningful macroscopic time scale. We find that for more general transitions, the equivalence between MAT and MPLT does not hold. Unlike other critical time definitions, we show that it is possible to evaluate the MAT without solving the underlying partial differential equation (pde). This makes MAT a simple and attractive quantity for practical situations. Finally, our work explores the accuracy of certain approximations derived using MAT, showing that useful approximations for nonlinear kinetic processes can be obtained, again without treating the governing pde directly.

  6. Critical Slowing Down in Time-to-Extinction: An Example of Critical Phenomena in Ecology

    NASA Technical Reports Server (NTRS)

    Gandhi, Amar; Levin, Simon; Orszag, Steven

    1998-01-01

    We study a model for two competing species that explicitly accounts for effects due to discreteness, stochasticity and spatial extension of populations. The two species are equally preferred by the environment and do better when surrounded by others of the same species. We observe that the final outcome depends on the initial densities (uniformly distributed in space) of the two species. The observed phase transition is a continuous one and key macroscopic quantities like the correlation length of clusters and the time-to-extinction diverge at a critical point. Away from the critical point, the dynamics can be described by a mean-field approximation. Close to the critical point, however, there is a crossover to power-law behavior because of the gross mismatch between the largest and smallest scales in the system. We have developed a theory based on surface effects, which is in good agreement with the observed behavior. The course-grained reaction-diffusion system obtained from the mean-field dynamics agrees well with the particle system.

  7. Critical Time Intervention: Model Description and Implications for the Significance of Timing in Social Work Interventions

    ERIC Educational Resources Information Center

    Herman, Daniel B.; Mandiberg, James M.

    2010-01-01

    Relatively little attention has been paid to the dimension of time in the design of social work interventions. Critical time intervention (CTI), an empirically supported psychosocial intervention intended to reduce the risk of homelessness by enhancing continuity of support for individuals with severe mental illness (SMI) during the transition…

  8. [Critical time intervention for individuals with first episode psychosis].

    PubMed

    Alvarado, Ruben; Schilling, Sara; Jorquera, María José

    2015-01-01

    The necessity of providing individuals experiencing first episode psychosis with early, comprehensive, and effective treatment, in order to improve their long-term prognosis, has been widely recognized. However, despite the important role of psychosocial interventions in treatment, only a portion of patients receive this type of care, and it is often of poor quality, especially in countries with limited resources. The Critical Time Intervention (CTI) model has been shown to effectively improve clinical and social outcomes of individuals with a history of psychosis, while also being cost-effective. It is a time-limited, community-based intervention, carried out by technical community workers who are specifically trained and continuously supervised by professionals. Therefore, CTI is a promising psychosocial intervention model for individuals experiencing a first psychotic episode, in countries with limited mental health service resources. PMID:27107285

  9. The influence of "quiet time" for patients in critical care.

    PubMed

    Maidl, Carolyn A; Leske, Jane S; Garcia, Annette E

    2014-10-01

    The primary aim was to examine the influence of "quiet time" in critical care. A dual-unit, nonrandomized, uncontrolled trial of a quiet time (QT) protocol was completed. A sample of adult patients from the Neurosciences Intensive Care Unit (NICU) and Cardiovascular Intensive Care Unit (CVICU) participated. Environmental stressors were reduced and patient rest promoted prior to QT. One hundred twenty-nine patients participated in 205 QTs. A one-way, repeated measure analysis of covariance (ANCOVA) was calculated comparing Richards-Campbell Sleep Questionnaire scores, pain and anxiety over three consecutive QTs. No significant statistical effect was found. However, patients rated sleep higher and anxiety levels decreased over consecutive QTs. Ninety-three percent of patients reported QT mattered to them. The combined efforts of nursing, medicine, and ancillary staff are necessary to foster periods of uninterrupted rest, thereby optimizing patient care. Further research is needed to determine if successive QTs positively influence patient outcomes. PMID:23847172

  10. Critical Probabilities and Convergence Time of Percolation Probabilistic Cellular Automata

    NASA Astrophysics Data System (ADS)

    Taggi, Lorenzo

    2015-05-01

    This paper considers a class of probabilistic cellular automata undergoing a phase transition with an absorbing state. Denoting by the neighbourhood of site , the transition probability is if or otherwise, . For any there exists a non-trivial critical probability that separates a phase with an absorbing state from a fluctuating phase. This paper studies how the neighbourhood affects the value of and provides lower bounds for . Furthermore, by using dynamic renormalization techniques, we prove that the expected convergence time of the processes on a finite space with periodic boundaries grows exponentially (resp. logarithmically) with the system size if (resp. ). This provides a partial answer to an open problem in Toom et al. (Stochastic Cellular Systems: Ergodicity, Memory, Morphogenesis, pp. 1-182. Manchester University Press, Manchester, 1990; Topics in Contemporary Probability and its Applications, pp. 117-157. CRC Press, Boca Raton, 1995).

  11. Critical source times for nutrient loss in agricultural catchment streams

    NASA Astrophysics Data System (ADS)

    Melland, Alice; Shore, Mairead; Mellander, Per-Erik; McDonald, Noeleen; Shortle, Ger; Murphy, Paul; Jordan, Phil

    2014-05-01

    Identifying periods of the year when there is a high risk of incidental nutrient loss from farms via runoff to streams underpins current nutrient management legislation in Europe. This research explored high-temporal resolution nutrient transfer patterns relative to the time that manure and fertiliser are prohibited from being spread (the mandatory spreading 'closed' period) in five Irish agricultural catchments. Catchment nutrient losses during the 12 week closed periods in 2009-10, 2010-11 and 2011-12 were compared with losses during the remainder of the year, and with losses in the two week 'shoulder' periods immediately before and after the closed period. The closed period losses were assumed to be residual from soil nutrient stores and the 'shoulder' periods were considered to also include incidental losses. Nutrient loss was measured at sub-hourly frequency as total phosphorus (P) and total oxidised nitrogen (mostly nitrate-N) fluxes in streamflow. The streamflow fluxes showed that the proportion of the annual nitrate-N loss occurring during the closed periods (33-61%) was high compared with the remainder of the year. Six to ten times more nitrate-N loss occurred in the two weeks after, compared with the two weeks before, the closed period. These two week 'shoulder' period losses were, on average, less than or equal to 2.5 kg nitrate-N/ha and 9% of total annual nitrate-N loss in streamflow. On average, 40-53% of the annual P loss occurred during the closed periods but in a runoff-prone catchment in a year with a wet summer, the closed period was the less risky period. Similar to nitrate-N, two to twenty times more P loss occurred in the two weeks after, compared with the two weeks before, the closed period. These shoulder period losses were, on average, less than or equal to 0.027 kg/ha and 4.2% of total annual P loss in streamflow. The proportion of the shoulder period loss that could be attributed to recently spread nutrients was not known but can be

  12. Scheduling Real-Time Mixed-Criticality Jobs

    NASA Astrophysics Data System (ADS)

    Baruah, Sanjoy K.; Bonifaci, Vincenzo; D'Angelo, Gianlorenzo; Li, Haohan; Marchetti-Spaccamela, Alberto; Megow, Nicole; Stougie, Leen

    Many safety-critical embedded systems are subject to certification requirements; some systems may be required to meet multiple sets of certification requirements, from different certification authorities. Certification requirements in such "mixed-criticality" systems give rise to interesting scheduling problems, that cannot be satisfactorily addressed using techniques from conventional scheduling theory. In this paper, we study a formal model for representing such mixed-criticality workloads. We demonstrate first the intractability of determining whether a system specified in this model can be scheduled to meet all its certification requirements, even for systems subject to two sets of certification requirements. Then we quantify, via the metric of processor speedup factor, the effectiveness of two techniques, reservation-based scheduling and priority-based scheduling, that are widely used in scheduling such mixed-criticality systems, showing that the latter of the two is superior to the former. We also show that the speedup factors are tight for these two techniques.

  13. Seeking worldwide professional consensus on the principles of end-of-life care for the critically ill. The Consensus for Worldwide End-of-Life Practice for Patients in Intensive Care Units (WELPICUS) study.

    PubMed

    Sprung, Charles L; Truog, Robert D; Curtis, J Randall; Joynt, Gavin M; Baras, Mario; Michalsen, Andrej; Briegel, Josef; Kesecioglu, Jozef; Efferen, Linda; De Robertis, Edoardo; Bulpa, Pierre; Metnitz, Philipp; Patil, Namrata; Hawryluck, Laura; Manthous, Constantine; Moreno, Rui; Leonard, Sara; Hill, Nicholas S; Wennberg, Elisabet; McDermid, Robert C; Mikstacki, Adam; Mularski, Richard A; Hartog, Christiane S; Avidan, Alexander

    2014-10-15

    Great differences in end-of-life practices in treating the critically ill around the world warrant agreement regarding the major ethical principles. This analysis determines the extent of worldwide consensus for end-of-life practices, delineates where there is and is not consensus, and analyzes reasons for lack of consensus. Critical care societies worldwide were invited to participate. Country coordinators were identified and draft statements were developed for major end-of-life issues and translated into six languages. Multidisciplinary responses using a web-based survey assessed agreement or disagreement with definitions and statements linked to anonymous demographic information. Consensus was prospectively defined as >80% agreement. Definitions and statements not obtaining consensus were revised based on comments of respondents, and then translated and redistributed. Of the initial 1,283 responses from 32 countries, consensus was found for 66 (81%) of the 81 definitions and statements; 26 (32%) had >90% agreement. With 83 additional responses to the original questionnaire (1,366 total) and 604 responses to the revised statements, consensus could be obtained for another 11 of the 15 statements. Consensus was obtained for informed consent, withholding and withdrawing life-sustaining treatment, legal requirements, intensive care unit therapies, cardiopulmonary resuscitation, shared decision making, medical and nursing consensus, brain death, and palliative care. Consensus was obtained for 77 of 81 (95%) statements. Worldwide consensus could be developed for the majority of definitions and statements about end-of-life practices. Statements achieving consensus provide standards of practice for end-of-life care; statements without consensus identify important areas for future research. PMID:25162767

  14. Accessible high performance computing solutions for near real-time image processing for time critical applications

    NASA Astrophysics Data System (ADS)

    Bielski, Conrad; Lemoine, Guido; Syryczynski, Jacek

    2009-09-01

    High Performance Computing (HPC) hardware solutions such as grid computing and General Processing on a Graphics Processing Unit (GPGPU) are now accessible to users with general computing needs. Grid computing infrastructures in the form of computing clusters or blades are becoming common place and GPGPU solutions that leverage the processing power of the video card are quickly being integrated into personal workstations. Our interest in these HPC technologies stems from the need to produce near real-time maps from a combination of pre- and post-event satellite imagery in support of post-disaster management. Faster processing provides a twofold gain in this situation: 1. critical information can be provided faster and 2. more elaborate automated processing can be performed prior to providing the critical information. In our particular case, we test the use of the PANTEX index which is based on analysis of image textural measures extracted using anisotropic, rotation-invariant GLCM statistics. The use of this index, applied in a moving window, has been shown to successfully identify built-up areas in remotely sensed imagery. Built-up index image masks are important input to the structuring of damage assessment interpretation because they help optimise the workload. The performance of computing the PANTEX workflow is compared on two different HPC hardware architectures: (1) a blade server with 4 blades, each having dual quad-core CPUs and (2) a CUDA enabled GPU workstation. The reference platform is a dual CPU-quad core workstation and the PANTEX workflow total computing time is measured. Furthermore, as part of a qualitative evaluation, the differences in setting up and configuring various hardware solutions and the related software coding effort is presented.

  15. Oral transit time: a critical review of the literature

    PubMed Central

    SOARES, Thais Jacóe; MORAES, Danielle Pedroni; de MEDEIROS, Gisele Chagas; SASSI, Fernanda Chiarion; ZILBERSTEIN, Bruno; de ANDRADE, Claudia Regina Furquim

    2015-01-01

    Introduction Oral transit time is one of the parameters observed during the clinical assessment of the swallowing function. The importance of this parameter is due to its impact on the total duration of a meal, whose consequence can be an unfavorable nutritional prognostic. Objective To document scientific papers that measure oral transit time in healthy subjects. Method The review followed the steps proposed by the Cochrane Handbook. The search was done via the PubMed database through the use of descriptors related to the oral phase of swallowing, as well as to types of food consistency. Results The articles on the theme had different definitions for oral transit time, as well as heterogeneity of tested volumes, age and gender of the participants. The times found varied from 0.35 s to 1.54 s for liquids, from 0.39 s to 1.05 s for pasty foods and from 1 s to 12.8 s for solid foods. Also, regardless of volume or consistency, oral transit time in elderly people is significantly longer than in adults. Conclusion There's no consensus in the literature about oral transit time in healthy subjects. However, this parameter should be valued during the assessment of the swallowing function due to its negative impact on the dynamics of swallowing, which can cause high energy expenditure during feeding. PMID:26176255

  16. Advancing critical care: time to kiss the right frog

    PubMed Central

    2013-01-01

    The greatest advances in critical care over the past two decades have been achieved through doing less to the patient. We have learnt through salutary experience that our burgeoning Master-of-the-Universe capabilities and the oh-so-obvious stratagems instilled in us from youth were often ineffective or even deleterious. This re-education process, however, is far from complete. We are now rightly agonizing over the need for better characterization of pathophysiology, earlier identification of disease processes and a more directed approach to therapeutic intervention. We need to delineate the point at which intrinsic and protective adaptation ends and true harmful pathology begins, and how our iatrogenic meddling either helps or hinders. We need to improve trial design in the heterogeneous populations we treat, and to move away from syndromic fixations that, while offering convenience, have generally proved counterproductive. Importantly, we need to discover a far more holistic approach to patient care, evolving from the prevailing overmedicalized, number-crunching perspective towards a true multidisciplinary effort that embraces psychological as well as physiological well-being, with appropriate pharmacological minimization or supplementation. Complacency, with an unfair apportion of blame on the patient for not getting better, is the biggest threat to continued improvement. PMID:23514321

  17. A Critical Analysis of Time Allocation in Psychoeducational Evaluations

    ERIC Educational Resources Information Center

    Taub, Gordon E.; Valentine, Jennifer

    2014-01-01

    This study provides results form a national survey examining school psychologists' allocation of time in psychoeducational evaluations. A total of 177 participants with an average of 13.45 years professional experience in school psychology, representing 39 states, participated in the survey. The results indicate that school psychologists spend the…

  18. Optimal time-critical scheduling via resource augmentation

    SciTech Connect

    Phillips, C.A.; Stein, C.; Torng, E.; Wein, J.

    1997-04-01

    We consider two fundamental problems in dynamic scheduling: scheduling to meet deadlines in a preemptive multiprocessor setting, and scheduling to provide good response time in a number of scheduling environments. When viewed from the perspective of traditional worst-case analysis, no good on-line algorithms exist for these problems, and for some variants no good off-line algorithms exist unless {Rho} = {Nu}{Rho}. We study these problems using a relaxed notion of competitive analysis, introduced by Kalyanasundaram and Pruhs, in which the on-line algorithm is allowed more resources than the optimal off-line algorithm to which it is compared. Using this approach, we establish that several well-known on-line algorithms, that have poor performance from an absolute worst-case perspective, are optimal for the problems in question when allowed moderately more resources. For the optimization of average flow time, these are the first results of any sort, for any {Nu}{Rho}-hard version of the problem, that indicate that it might be possible to design good approximation algorithms.

  19. Automatic Verification of Timing Constraints for Safety Critical Space Systems

    NASA Astrophysics Data System (ADS)

    Fernandez, Javier; Parra, Pablo; Sanchez Prieto, Sebastian; Polo, Oscar; Bernat, Guillem

    2015-09-01

    In this paper is presented an automatic process of verification. We focus in the verification of scheduling analysis parameter. This proposal is part of process based on Model Driven Engineering to automate a Verification and Validation process of the software on board of satellites. This process is implemented in a software control unit of the energy particle detector which is payload of Solar Orbiter mission. From the design model is generated a scheduling analysis model and its verification model. The verification as defined as constraints in way of Finite Timed Automatas. When the system is deployed on target the verification evidence is extracted as instrumented points. The constraints are fed with the evidence, if any of the constraints is not satisfied for the on target evidence the scheduling analysis is not valid.

  20. Application of queueing models to multiprogrammed computer systems operating in a time-critical environment

    NASA Technical Reports Server (NTRS)

    Eckhardt, D. E., Jr.

    1979-01-01

    A model of a central processor (CPU) which services background applications in the presence of time critical activity is presented. The CPU is viewed as an M/M/1 queueing system subject to periodic interrupts by deterministic, time critical process. The Laplace transform of the distribution of service times for the background applications is developed. The use of state of the art queueing models for studying the background processing capability of time critical computer systems is discussed and the results of a model validation study which support this application of queueing models are presented.

  1. The stability of the critical scaling against the time-dependent perturbation

    NASA Astrophysics Data System (ADS)

    Park, Heungsik; Park, Hyunggyu

    2004-04-01

    We study the stability of critical scaling against the time-dependent perturbation in the contact process(CP) model. The critical probability of the particle varies asp = p0 + ct-α. we perform the static Monte Carlo simulation using the finite size scaling theory in the steady state. For the α > 1/v∥, the time dependent perturbation is irrelevant, therefore , the critical exponents β/v∥,β/v⊥ have the DP value. For the α = 1/v∥, β/v∥ is DP value but β/v⊥ is varied with perturbation strength c. For the α < 1/v∥, the particle density is decayed with ρ ˜ tαβ in thermodynamic limit. However, for the all case, z have DP value. To study the stability of critical scaling, we introduce the time-dependent perturbation and know that critical scaling function is satisfied in all cases. Numerical simulations confirm our predictions.

  2. Incubation time for sub-critical crack propagation in SiC-SiC composites

    SciTech Connect

    El-Azab, A.; Ghoniem, N.M.

    1995-04-01

    The objective of this work is to investigate the time for sub-critical crack propagation is SiC-SiC composites at high temperatures. The effects of fiber thermal creep on the relaxation of crack bridging tractions in SiC-SiC ceramic matrix composites (CMCs) is considered in the present work, with the objective of studying the time-to propagation of sub-critical matrix cracks in this material at high temperatures. Under the condition of fiber stress relaxation in the bridiging zone, it is found that the crack opening and the stress intensity factor increase with time for sub-critical matrix cracks. The time elapsed before the stress intensity reaches the critical value for crack propagation is calculated as a function of the initial crack length, applied stress and temperature. Stability domains for matrix cracks are defined, which provide guidelines for conducting high-temperature crack propagation experiments.

  3. Methods for detecting early warnings of critical transitions in time series illustrated using simulated ecological data.

    PubMed

    Dakos, Vasilis; Carpenter, Stephen R; Brock, William A; Ellison, Aaron M; Guttal, Vishwesha; Ives, Anthony R; Kéfi, Sonia; Livina, Valerie; Seekell, David A; van Nes, Egbert H; Scheffer, Marten

    2012-01-01

    Many dynamical systems, including lakes, organisms, ocean circulation patterns, or financial markets, are now thought to have tipping points where critical transitions to a contrasting state can happen. Because critical transitions can occur unexpectedly and are difficult to manage, there is a need for methods that can be used to identify when a critical transition is approaching. Recent theory shows that we can identify the proximity of a system to a critical transition using a variety of so-called 'early warning signals', and successful empirical examples suggest a potential for practical applicability. However, while the range of proposed methods for predicting critical transitions is rapidly expanding, opinions on their practical use differ widely, and there is no comparative study that tests the limitations of the different methods to identify approaching critical transitions using time-series data. Here, we summarize a range of currently available early warning methods and apply them to two simulated time series that are typical of systems undergoing a critical transition. In addition to a methodological guide, our work offers a practical toolbox that may be used in a wide range of fields to help detect early warning signals of critical transitions in time series data. PMID:22815897

  4. Methods for Detecting Early Warnings of Critical Transitions in Time Series Illustrated Using Simulated Ecological Data

    PubMed Central

    Dakos, Vasilis; Carpenter, Stephen R.; Brock, William A.; Ellison, Aaron M.; Guttal, Vishwesha; Ives, Anthony R.; Kéfi, Sonia; Livina, Valerie; Seekell, David A.; van Nes, Egbert H.; Scheffer, Marten

    2012-01-01

    Many dynamical systems, including lakes, organisms, ocean circulation patterns, or financial markets, are now thought to have tipping points where critical transitions to a contrasting state can happen. Because critical transitions can occur unexpectedly and are difficult to manage, there is a need for methods that can be used to identify when a critical transition is approaching. Recent theory shows that we can identify the proximity of a system to a critical transition using a variety of so-called ‘early warning signals’, and successful empirical examples suggest a potential for practical applicability. However, while the range of proposed methods for predicting critical transitions is rapidly expanding, opinions on their practical use differ widely, and there is no comparative study that tests the limitations of the different methods to identify approaching critical transitions using time-series data. Here, we summarize a range of currently available early warning methods and apply them to two simulated time series that are typical of systems undergoing a critical transition. In addition to a methodological guide, our work offers a practical toolbox that may be used in a wide range of fields to help detect early warning signals of critical transitions in time series data. PMID:22815897

  5. Critical Issue Bibliography (CRIB) Sheet: Part-Time and Adjunct Faculty.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Higher Education, Washington, DC.

    This CRitical Issue Bibliography (CRIB) Sheet focuses on issues related to part-time and adjunct faculty. It is clear that part-time faculty are now a substantial entity within academe and need to be understood better. This CRIB sheet lists resources that address: (1) trends in contracts, numbers, or conditions of part-time faculty; (2) issues…

  6. Developmental critical windows and sensitive periods as three-dimensional constructs in time and space.

    PubMed

    Burggren, Warren W; Mueller, Casey A

    2015-01-01

    A critical window (sensitive period) represents a period during development when an organism's phenotype is responsive to intrinsic or extrinsic (environmental) factors. Such windows represent a form of developmental phenotypic plasticity and result from the interaction between genotype and environment. Critical windows have typically been defined as comprising discrete periods in development with a distinct starting time and end time, as identified by experiments following an on and an off protocol. Yet in reality, periods of responsiveness during development are likely more ambiguous that depicted. Our goal is to extend the concept of the developmental critical window by introducing a three-dimensional construct in which time during development, dose of the stressor applied, and the resultant phenotypic modification can be utilized to more realistically define a critical window. Using the example of survival of the brine shrimp (Artemia franciscana) during exposure to different salinity levels during development, we illustrate that it is not just stressor dose or exposure time but the interaction of these two factors that results in the measured phenotypic change, which itself may vary within a critical window. We additionally discuss a systems approach to critical windows, in which the components of a developing system--whether they be molecular, physiological, or morphological--may show differing responses with respect to time and dose. Thus, the plasticity of each component may contribute to a broader overall system response. PMID:25730265

  7. Critical short-time dynamics in a system with interacting static and diffusive populations.

    PubMed

    Argolo, C; Quintino, Yan; Gleria, Iram; Lyra, M L

    2012-01-01

    We study the critical short-time dynamical behavior of a one-dimensional model where diffusive individuals can infect a static population upon contact. The model presents an absorbing phase transition from an active to an inactive state. Previous calculations of the critical exponents based on quasistationary quantities have indicated an unusual crossover from the directed percolation to the diffusive contact process universality classes. Here we show that the critical exponents governing the slow short-time dynamic evolution of several relevant quantities, including the order parameter, its relative fluctuations, and correlation function, reinforce the lack of universality in this model. Accurate estimates show that the critical exponents are distinct in the regimes of low and high recovery rates. PMID:22400516

  8. Supervisory-level interruption recovery in time-critical control tasks.

    PubMed

    Sasangohar, Farzan; Scott, Stacey D; Cummings, M L

    2014-07-01

    This paper investigates the effectiveness of providing interruption recovery assistance in the form of an interactive visual timeline of historical events on a peripheral display in support of team supervision in time-critical settings. As interruptions can have detrimental effects on task performance, particularly in time-critical work environments, there is growing interest in the design of tools to assist people in resuming their pre-interruption activity. A user study was conducted to evaluate the use of an interactive event timeline that provides assistance to human supervisors in time-critical settings. The study was conducted in an experimental platform that emulated a team of operators and a mission commander performing a time-critical unmanned aerial vehicle (UAV) mission. The study results showed that providing interruption assistance enabled people to recover from interruptions faster and more accurately. These results have implications for interface design that could be adopted in similar time-critical environments such as air-traffic control, process control, and first responders. PMID:24581931

  9. Time-keeping in the antipodes: a critical comparison of the Sydney and Littelton time balls

    NASA Astrophysics Data System (ADS)

    Kinns, Roger

    2009-07-01

    Maudslay, Sons & Field built the time ball apparatus for Sydney, New South Wales (NSW) in 1855, and to hoist the ball they used a rack and pinion that was developed from the mechanism found at Edinburgh and Deal. Sydney's time ball became operational in 1858, following completion of Sydney Observatory (which included a time ball tower). Henry Russell, the NSW Government Astronomer, modified this apparatus to a limited extent during the 1870s, but most principal features were retained. The apparatus for Lyttelton, New Zealand, was ordered in 1873 and shipped from London in 1874 by Siemens Brothers. lt, too, had to await completion of the necessary tower, and became operational in 1876. Both Antipodean time balls were still working in 2009. In this paper it is demonstrated that the apparatus at Lyttelton is a replica of the 1855 design used in Sydney, despite the long interval between their dates of supply. The only surviving note in Maudslays' records about an 1873 time ball indicates provision for the Cape of Good Hope and an association with Siemens. A time ball was installed at Alfred Docks in Cape Town during 1873, but available evidence indicates that it was unlikely to have been built by Maudslays. lt is suggested that Maudslays' 1873 apparatus was instead sold to Siemens Brothers who installed it at Lyttelton. No Siemens records showing the supply of time balls to other locations at this time have been found.

  10. Natural time analysis of critical phenomena: The case of pre-fracture electromagnetic emissions

    SciTech Connect

    Potirakis, S. M.; Karadimitrakis, A.; Eftaxias, K.

    2013-06-15

    Criticality of complex systems reveals itself in various ways. One way to monitor a system at critical state is to analyze its observable manifestations using the recently introduced method of natural time. Pre-fracture electromagnetic (EM) emissions, in agreement to laboratory experiments, have been consistently detected in the MHz band prior to significant earthquakes. It has been proposed that these emissions stem from the fracture of the heterogeneous materials surrounding the strong entities (asperities) distributed along the fault, preventing the relative slipping. It has also been proposed that the fracture of heterogeneous material could be described in analogy to the critical phase transitions in statistical physics. In this work, the natural time analysis is for the first time applied to the pre-fracture MHz EM signals revealing their critical nature. Seismicity and pre-fracture EM emissions should be two sides of the same coin concerning the earthquake generation process. Therefore, we also examine the corresponding foreshock seismic activity, as another manifestation of the same complex system at critical state. We conclude that the foreshock seismicity data present criticality features as well.

  11. Critical time span and nonlinear action structure of climatic atmosphere and ocean

    NASA Astrophysics Data System (ADS)

    Wang, Z. R.; Wu, D. X.; Chen, D. K.; Wu, H. D.; Song, X. J.; Zhang, Z. H.

    2002-07-01

    This paper studies the critical time span and the approximate nonlinear action structure of climatic atmosphere and ocean. The critical time span of the climatic atmosphere and ocean, which is related to the spatial resolution required, the strength of nonlinear action, and the calculation exactness, may represent the relative temporal scale of predictability. As far as the same characteristic spatial scale is concerned, the minimum critical time span of the ocean is about 9 times of that of atmosphere, several days or more. Usually, the stronger the nonlinear action, the shorter the critical time span with smooth changes of external forces. The approximate structure of nonlinear action of climatic atmosphere and ocean is: the nonlinear action decreases usually with increasing latitude, which is related to the role of the Coriolis force in fluid motion (forming geostrophic current); the nonlinear action changes with the anomalous cyclonic or anticyclonic circulation shear, for instance, when the strength of anomalous eastward zonal circulation is comparable to that of anomalous meridional circulation, the nonlinear action is the strongest; wind stress plus gradient forces enhance the nonlinear action, etc..

  12. Critical ischemia time in a model of spinal cord section. A study performed on dogs

    PubMed Central

    Garcia Martinez, David; Rosales Corral, Sergio A.; Flores Soto, Mario E.; Velarde Silva, Gustavo; Portilla de Buen, Eliseo

    2006-01-01

    Vascular changes after acute spinal cord trauma are important factors that predispose quadriplegia, in most cases irreversible. Repair of the spinal blood flow helps the spinal cord recovery. The average time to arrive and perform surgery is 3 h in most cases. It is important to determine the critical ischemia time in order to offer better functional prognosis. A spinal cord section and vascular clamping of the spinal anterior artery at C5–C6 model was used to determine critical ischemia time. The objective was to establish a critical ischemia time in a model of acute spinal cord section. Four groups of dogs were used, anterior approach and vascular clamp of spinal anterior artery with 1, 2, 3, and 4 h of ischemia and posterior hemisection of spinal cord at C5–C6 was performed. Clinical evaluation was made during 12 weeks and morphological evaluation at the end of this period. We obtained a maximal neurological coordination at 23 days average. Two cases showed sequels of right upper limb paresis at 1 and 3 ischemia hours. There was nerve conduction delay of 56% at 3 h of ischemia. Morphological examination showed 25% of damaged area. The VIII and IX Rexed’s laminae were the most affected. The critical ischemia time was 3 h. Dogs with 4 h did not exhibit any recovery. PMID:17024402

  13. Kibble-Zurek mechanism beyond adiabaticity: Finite-time scaling with critical initial slip

    NASA Astrophysics Data System (ADS)

    Huang, Yingyi; Yin, Shuai; Hu, Qijun; Zhong, Fan

    2016-01-01

    The Kibble-Zurek mechanism demands an initial adiabatic stage before an impulse stage to have a frozen correlation length that generates topological defects in a cooling phase transition. Here we study such a driven critical dynamics but with an initial condition that is near the critical point and that is far away from equilibrium. In this case, there is no initial adiabatic stage at all and thus adiabaticity is broken. However, we show that there again exists a finite length scale arising from the driving that divides the evolution into three stages. A relaxation-finite-time-scaling-adiabatic scenario is then proposed in place of the adiabatic-impulse-adiabatic scenario of the original Kibble-Zurek mechanism. A unified scaling theory, which combines finite-time scaling with critical initial slip, is developed to describe the universal behavior and is confirmed with numerical simulations of a two-dimensional classical Ising model.

  14. Identifying the Critical Time Period for Information Extraction when Recognizing Sequences of Play

    ERIC Educational Resources Information Center

    North, Jamie S.; Williams, A. Mark

    2008-01-01

    The authors attempted to determine the critical time period for information extraction when recognizing play sequences in soccer. Although efforts have been made to identify the perceptual information underpinning such decisions, no researchers have attempted to determine "when" this information may be extracted from the display. The authors…

  15. Pedagogy in Catastrophic Times: Giroux and the Tasks of Critical Public Intellectuals

    ERIC Educational Resources Information Center

    Morris, Doug

    2012-01-01

    This article reflects on Henry Giroux's work as a critical public intellectual and the important role his work plays in fostering educated hope and insurgent possibilities during our present times of daily and longer term catastrophes. In addition to attempting to capture the experience of what it means and how it feels to read Giroux along with…

  16. Burst wait time simulation of CALIBAN reactor at delayed super-critical state

    SciTech Connect

    Humbert, P.; Authier, N.; Richard, B.; Grivot, P.; Casoli, P.

    2012-07-01

    In the past, the super prompt critical wait time probability distribution was measured on CALIBAN fast burst reactor [4]. Afterwards, these experiments were simulated with a very good agreement by solving the non-extinction probability equation [5]. Recently, the burst wait time probability distribution has been measured at CEA-Valduc on CALIBAN at different delayed super-critical states [6]. However, in the delayed super-critical case the non-extinction probability does not give access to the wait time distribution. In this case it is necessary to compute the time dependent evolution of the full neutron count number probability distribution. In this paper we present the point model deterministic method used to calculate the probability distribution of the wait time before a prescribed count level taking into account prompt neutrons and delayed neutron precursors. This method is based on the solution of the time dependent adjoint Kolmogorov master equations for the number of detections using the generating function methodology [8,9,10] and inverse discrete Fourier transforms. The obtained results are then compared to the measurements and Monte-Carlo calculations based on the algorithm presented in [7]. (authors)

  17. Critical capacity, travel time delays and travel time distribution of rapid mass transit systems

    NASA Astrophysics Data System (ADS)

    Legara, Erika Fille; Monterola, Christopher; Lee, Kee Khoon; Hung, Gih Guang

    2014-07-01

    We set up a mechanistic agent-based model of a rapid mass transit system. Using empirical data from Singapore’s unidentifiable smart fare card, we validate our model by reconstructing actual travel demand and duration of travel statistics. We subsequently use this model to investigate two phenomena that are known to significantly affect the dynamics within the RTS: (1) overloading in trains and (2) overcrowding in the RTS platform. We demonstrate that by varying the loading capacity of trains, a tipping point emerges at which an exponential increase in the duration of travel time delays is observed. We also probe the impact on the rail system dynamics of three types of passenger growth distribution across stations: (i) Dirac delta, (ii) uniform and (iii) geometric, which is reminiscent of the effect of land use on transport. Under the assumption of a fixed loading capacity, we demonstrate the dependence of a given origin-destination (OD) pair on the flow volume of commuters in station platforms.

  18. Cyber-Critical Infrastructure Protection Using Real-Time Payload-Based Anomaly Detection

    NASA Astrophysics Data System (ADS)

    Düssel, Patrick; Gehl, Christian; Laskov, Pavel; Bußer, Jens-Uwe; Störmann, Christof; Kästner, Jan

    With an increasing demand of inter-connectivity and protocol standardization modern cyber-critical infrastructures are exposed to a multitude of serious threats that may give rise to severe damage for life and assets without the implementation of proper safeguards. Thus, we propose a method that is capable to reliably detect unknown, exploit-based attacks on cyber-critical infrastructures carried out over the network. We illustrate the effectiveness of the proposed method by conducting experiments on network traffic that can be found in modern industrial control systems. Moreover, we provide results of a throughput measuring which demonstrate the real-time capabilities of our system.

  19. Regulatory compliance issues related to the White Oak Creek Embayment time-critical removal action

    SciTech Connect

    Leslie, M. ); Kimmel, B.L. )

    1991-01-01

    In September 1990, Martin Marietta Energy Systems (Energy Systems) discovered high levels of Cesium-137 ({sup 137}Cs) in surface sedimenus near the mouth of White Oak Creek Embayment (WOCE). White Oak Creek (WOC) receives surface water drainage from Oak Ridge National Laboratory. Since this discovery, the Department of Energy (DOE) and Energy Systems have pursued actions designed to stabilize the contaminated WOCE sediments under provisions of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), and the implementing regulations in the National Contingency Plan (NCP) (40 CFR Part 300), as a time-critical removal action. By definition, a time-critical removal is an action where onsite activities are initiated within six months of the determination that a removal action is appropriate. Time-critical removal actions allow comparatively rapid mobilization to protect human health and the environment without going through the lengthy and extensive CERCLA Remedial Investigation/Feasibility Study/Record of Decision process. Many aspects of the project, in terms of compliance with the substantive requirements of the NCP and ARARs, have exceeded the regulatory requirements, despite the fact that there is no apparent authority on conducting removal actions at Federal facilities. Much of the interpretation of the NCP was groundbreaking in nature for both EPA and DOE. 4 refs., 2 figs.

  20. The Role of Time-Limited Trials in Dialysis Decision Making in Critically Ill Patients.

    PubMed

    Scherer, Jennifer S; Holley, Jean L

    2016-02-01

    Technologic advances, such as continuous RRT, provide lifesaving therapy for many patients. AKI in the critically ill patient, a fatal diagnosis in the past, is now often a survivable condition. Dialysis decision making for the critically ill patient with AKI is complex. What was once a question solely of survival now is nuanced by an individual's definition of quality of life, personal values, and short- and long-term prognoses. Clinical evaluation of AKI in the critically ill is multifaceted. Treatment decision making requires consideration of the natural evolution of the patient's AKI within the context of the global prognosis. Situations are often marked by prognostic uncertainty and clinical unknowns. In the face of these uncertainties, establishment of patient-directed therapies is imperative. A time-limited trial of continuous RRT in this setting is often appropriate but difficult to execute. Using patient preferences as a clinical guide, a proper time-limited trial requires assessment of prognosis, elicitation of patient values, strong communication skills, clear documentation, and often, appropriate integration of palliative care services. A well conducted time-limited trial can avoid interprofessional conflict and provide support for the patient, family, and staff. PMID:26450932

  1. Fairness of channel access for non-time-critical traffic using the FDDI token ring protocol

    NASA Technical Reports Server (NTRS)

    Johnson, M. J.

    1986-01-01

    The Fiber Distributed Data Interface (FDDI) is an ANSI draft proposed standard for a 100 megabit per second fiber optic token ring. FDDI supports two types of traffic, synchronous and asynchronous. Synchronous traffic is time critical traffic; stations are assigned guaranteed bandwidth to support their synchronous needs. Asynchronous traffic is lower priority and is sent only if time permits. It is proved analytically that the FDDI access protocol provides all stations on the ring with equal access to the channel to transmit asynchronous frames, regardless of the relative sizes of synchronous bandwidth allocations for individual stations. Analytic results are supported with data from simulation runs.

  2. Critical Spaces for Critical Times: Global Conversations in Literacy Research as an Open Professional Development and Practices Resource

    ERIC Educational Resources Information Center

    Albers, Peggy; Cho, A. Ram; Shin, Ji Hye; Pang, Myoung Eun; Angay-Crowder, Tuba; Jung, Jin Kyeong; Pace, Christi L.; Sena, Mandi; Turnbull, Sarah

    2015-01-01

    This paper reflects an OER (Open Educational Resources) critical literacy project, Global Conversations in Literacy Research (GCLR), (www.globalconversationsinliteracy.wordpress.com), now in its fourth year. GCLR annually hosts seven web seminars presented by internationally recognized literacy and education scholars. We outline key dimensions of…

  3. Real-time reinforcement learning by sequential Actor-Critics and experience replay.

    PubMed

    Wawrzyński, Paweł

    2009-12-01

    Actor-Critics constitute an important class of reinforcement learning algorithms that can deal with continuous actions and states in an easy and natural way. This paper shows how these algorithms can be augmented by the technique of experience replay without degrading their convergence properties, by appropriately estimating the policy change direction. This is achieved by truncated importance sampling applied to the recorded past experiences. It is formally shown that the resulting estimation bias is bounded and asymptotically vanishes, which allows the experience replay-augmented algorithm to preserve the convergence properties of the original algorithm. The technique of experience replay makes it possible to utilize the available computational power to reduce the required number of interactions with the environment considerably, which is essential for real-world applications. Experimental results are presented that demonstrate that the combination of experience replay and Actor-Critics yields extremely fast learning algorithms that achieve successful policies for non-trivial control tasks in considerably short time. Namely, the policies for the cart-pole swing-up [Doya, K. (2000). Reinforcement learning in continuous time and space. Neural Computation, 12(1), 219-245] are obtained after as little as 20 min of the cart-pole time and the policy for Half-Cheetah (a walking 6-degree-of-freedom robot) is obtained after four hours of Half-Cheetah time. PMID:19523786

  4. The concept of `critical earthquakes' applied to mine rockbursts with time-to-failure analysis

    NASA Astrophysics Data System (ADS)

    Ouillon, G.; Sornette, D.

    2000-11-01

    We report new tests, performed on rockbursts in deep South African mines, of the concept that large earthquakes are `critical points'. We extend the concept of an optimal time and space correlation region and test it on the eight main shocks of our catalogue, provided by the South African company ISS International. In a first test, we use the simplest signature of criticality in terms of a power-law time-to-failure formula. In spite of the fact that the search for the optimal correlation size is performed with this simple power law, we find evidence both for accelerated seismicity and for the presence of log-periodic behaviour in the cumulative Benioff strain with a preferred scaling factor close to 2. We then propose a new algorithm based on a space and time smoothing procedure, which is also intended to account for the finite range and finite duration of mechanical interactions between events. This new algorithm provides a much more robust and efficient construction of the optimal correlation region, which allows us to use the log-periodic formula directly in the search process. In this preliminary work, we have only tested the new algorithm on the largest event in the catalogue. The result is of remarkably good quality, with a dramatic improvement in accuracy and robustness. This confirms the potential importance of log-periodic signals. Our study opens the road for an efficient implementation of a systematic testing procedure of real-time predictions.

  5. Influence of time-dependent factors in the evaluation of critical infrastructure protection measures.

    SciTech Connect

    Buehring, W. A.; Samsa, M. E.; Decision and Information Sciences

    2008-03-28

    The examination of which protective measures are the most appropriate to be implemented in order to prevent, protect against, respond to, and recover from attacks on critical infrastructures and key resources typically involves a comparison of the consequences that could occur when the protective measure is implemented to those that could occur when it is not. This report describes a framework for evaluation that provides some additional capabilities for comparing optional protective measures. It illustrates some potentially important time-dependent factors, such as the implementation rate, that affect the relative pros and cons associated with widespread implementation of protective measures. It presents example results from the use of protective measures, such as detectors and pretrained responders, for an illustrative biological incident. Results show that the choice of an alternative measure can depend on whether or not policy and financial support can be maintained for extended periods of time. Choice of a time horizon greatly influences the comparison of alternatives.

  6. Automated implementation of rule-based expert systems with neural networks for time-critical applications

    NASA Technical Reports Server (NTRS)

    Ramamoorthy, P. A.; Huang, Song; Govind, Girish

    1991-01-01

    In fault diagnosis, control and real-time monitoring, both timing and accuracy are critical for operators or machines to reach proper solutions or appropriate actions. Expert systems are becoming more popular in the manufacturing community for dealing with such problems. In recent years, neural networks have revived and their applications have spread to many areas of science and engineering. A method of using neural networks to implement rule-based expert systems for time-critical applications is discussed here. This method can convert a given rule-based system into a neural network with fixed weights and thresholds. The rules governing the translation are presented along with some examples. We also present the results of automated machine implementation of such networks from the given rule-base. This significantly simplifies the translation process to neural network expert systems from conventional rule-based systems. Results comparing the performance of the proposed approach based on neural networks vs. the classical approach are given. The possibility of very large scale integration (VLSI) realization of such neural network expert systems is also discussed.

  7. Design oriented identification of critical times in transient response. [due to dynamic loads

    NASA Technical Reports Server (NTRS)

    Haftka, R. T.; Watson, L. T.; Grandhi, R. V.

    1984-01-01

    Two techniques are presented for reducing the computational effort in identifying the critical time points. One approach is an adaptive search technique, well suited for the case where the response is exactly known. The other technique, useful for noisy response, is based on a least-squares spline approximation of the response. The possibility of grouping several closely spaced local peaks to identify a single super peak from each group is also investigated. The computational efficiency of the techniques proposed here is illustrated by two examples.

  8. Reinforcement learning using a continuous time actor-critic framework with spiking neurons.

    PubMed

    Frémaux, Nicolas; Sprekeler, Henning; Gerstner, Wulfram

    2013-04-01

    Animals repeat rewarded behaviors, but the physiological basis of reward-based learning has only been partially elucidated. On one hand, experimental evidence shows that the neuromodulator dopamine carries information about rewards and affects synaptic plasticity. On the other hand, the theory of reinforcement learning provides a framework for reward-based learning. Recent models of reward-modulated spike-timing-dependent plasticity have made first steps towards bridging the gap between the two approaches, but faced two problems. First, reinforcement learning is typically formulated in a discrete framework, ill-adapted to the description of natural situations. Second, biologically plausible models of reward-modulated spike-timing-dependent plasticity require precise calculation of the reward prediction error, yet it remains to be shown how this can be computed by neurons. Here we propose a solution to these problems by extending the continuous temporal difference (TD) learning of Doya (2000) to the case of spiking neurons in an actor-critic network operating in continuous time, and with continuous state and action representations. In our model, the critic learns to predict expected future rewards in real time. Its activity, together with actual rewards, conditions the delivery of a neuromodulatory TD signal to itself and to the actor, which is responsible for action choice. In simulations, we show that such an architecture can solve a Morris water-maze-like navigation task, in a number of trials consistent with reported animal performance. We also use our model to solve the acrobot and the cartpole problems, two complex motor control tasks. Our model provides a plausible way of computing reward prediction error in the brain. Moreover, the analytically derived learning rule is consistent with experimental evidence for dopamine-modulated spike-timing-dependent plasticity. PMID:23592970

  9. Reinforcement Learning Using a Continuous Time Actor-Critic Framework with Spiking Neurons

    PubMed Central

    Frémaux, Nicolas; Sprekeler, Henning; Gerstner, Wulfram

    2013-01-01

    Animals repeat rewarded behaviors, but the physiological basis of reward-based learning has only been partially elucidated. On one hand, experimental evidence shows that the neuromodulator dopamine carries information about rewards and affects synaptic plasticity. On the other hand, the theory of reinforcement learning provides a framework for reward-based learning. Recent models of reward-modulated spike-timing-dependent plasticity have made first steps towards bridging the gap between the two approaches, but faced two problems. First, reinforcement learning is typically formulated in a discrete framework, ill-adapted to the description of natural situations. Second, biologically plausible models of reward-modulated spike-timing-dependent plasticity require precise calculation of the reward prediction error, yet it remains to be shown how this can be computed by neurons. Here we propose a solution to these problems by extending the continuous temporal difference (TD) learning of Doya (2000) to the case of spiking neurons in an actor-critic network operating in continuous time, and with continuous state and action representations. In our model, the critic learns to predict expected future rewards in real time. Its activity, together with actual rewards, conditions the delivery of a neuromodulatory TD signal to itself and to the actor, which is responsible for action choice. In simulations, we show that such an architecture can solve a Morris water-maze-like navigation task, in a number of trials consistent with reported animal performance. We also use our model to solve the acrobot and the cartpole problems, two complex motor control tasks. Our model provides a plausible way of computing reward prediction error in the brain. Moreover, the analytically derived learning rule is consistent with experimental evidence for dopamine-modulated spike-timing-dependent plasticity. PMID:23592970

  10. Timing of (supplemental) parenteral nutrition in critically ill patients: a systematic review

    PubMed Central

    2014-01-01

    Supplemental parenteral nutrition (SPN) is used in a step-up approach when full enteral support is contraindicated or fails to reach caloric targets. Recent nutrition guidelines present divergent advices regarding timing of SPN in critically ill patients ranging from early SPN (<48 h after admission; EPN) to postponing initiation of SPN until day 8 after Intensive Care Unit (ICU) admission (LPN). This systematic review summarizes results of prospective studies among adult ICU patients addressing the best timing of (supplemental) parenteral nutrition (S)PN. A structured PubMed search was conducted to identify eligible articles. Articles were screened and selected using predetermined criteria and appraised for relevance and validity. After critical appraisal, four randomized controlled trials (RCTs) and two prospective observational studies remained. One RCT found a higher percentage of alive discharge from the ICU at day 8 in the LPN group compared to EPN group (p = 0.007) but no differences in ICU and in-hospital mortality. None of the other RCTs found differences in ICU or in-hospital mortality rates. Contradicting or divergent results on other secondary outcomes were found for ICU length of stay, hospital length of stay, infection rates, nutrition targets, duration of mechanical ventilation, glucose control, duration of renal replacement therapy, muscle wasting and fat loss. Although the heterogeneity in quality and design of relevant studies precludes firm conclusions, it is reasonable to assume that in adult critically ill patients, there are no clinically relevant benefits of EPN compared with LPN with respect to morbidity or mortality end points, when full enteral support is contraindicated or fails to reach caloric targets. However, considering that infectious morbidity and resolution of organ failure may be negatively affected through mechanisms not yet clearly understood and acquisition costs of parenteral nutrition are higher, the early

  11. White Oak Creek Embayment time-critical CERCLA removal action sediment-retention structure

    SciTech Connect

    Not Available

    1992-09-01

    Over a 20-month period between September 1990 and April 1992, the Department of Energy (DOE), acting through Martin Marietta Energy Systems, Inc., managing contractor for the DOE Oak Ridge Field Office (DOE-OR), conducted a DOE-lead and DOE-funded time-critical removal action at the White Oak Creek Embayment (WOCE), pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The time-critical removal action specifically consisted of the design and construction of a sediment-retention structure across the mouth of WOCE to prevent off-site migration of sediments contaminated by cesium ([sup 137]Cs) into the Clinch River. Construction of a sediment-retention structure was completed in mid-April 1992. The purpose of this report is to meet the substantive requirements of 40 CFR 300.165 describing a complete report on the removal operation and the actions taken.'' This section of the NCP specifically addresses on-scene coordinator reports for the Environmental Protection Agency (EPA) Superfund-lead actions and includes several elements that are not applicable to this DOE-lead action. Only those sections that are pertinent and applicable are addressed in this final report.

  12. Self-organized criticality in COADS temperature time series: Implications for climate prediction

    SciTech Connect

    Selvam, A.M.; Joshi, R.R.; Vijayakumar, R.

    1994-12-31

    Continuous periodogram spectral analyses of global COADS seasonal (Sept.--Nov.) mean surface (air and sea) temperature time series for the 28-year period 1961--1988 show that the spectra follow the universal inverse power law form of the statistical normal distribution. The inverse power law form for power spectra of temporal fluctuations is ubiquitous to real-world dynamical systems and was recently identified as the temporal signature of self-organized criticality. Self-organized criticality implies long range temporal correlations (persistence or memory). The periodogram analyses also give the following results: (1) Periodicities up to 5 years contribute up to 50% of the total variance. (2) The spectra are broad-band with embedded dominant wavebands, the dominant bandwidth increasing with period length. (3) Spiral-like structure of atmospheric flows is seen in the continuous smooth rotation of the phase angle with increase in period length. The above results are consistent with a recently developed nondeterministic cell dynamical system model for atmospheric flows. Identification of a universal spectrum for temperature time series rules out linear secular trends in global surface (air and sea) temperatures The man-made greenhouse gas warming effect will result in energy propagation to all scales of weather and will be manifested immediately in the intensification of high-frequency fluctuations such as the quasi-biennial oscillation (QBO) and El Nino-Southern Oscillation (ENSO) cycles.

  13. A Time-Critical Adaptive Approach for Visualizing Natural Scenes on Different Devices

    PubMed Central

    Dong, Tianyang; Liu, Siyuan; Xia, Jiajia; Fan, Jing; Zhang, Ling

    2015-01-01

    To automatically adapt to various hardware and software environments on different devices, this paper presents a time-critical adaptive approach for visualizing natural scenes. In this method, a simplified expression of a tree model is used for different devices. The best rendering scheme is intelligently selected to generate a particular scene by estimating the rendering time of trees based on their visual importance. Therefore, this approach can ensure the reality of natural scenes while maintaining a constant frame rate for their interactive display. To verify its effectiveness and flexibility, this method is applied in different devices, such as a desktop computer, laptop, iPad and smart phone. Applications show that the method proposed in this paper can not only adapt to devices with different computing abilities and system resources very well but can also achieve rather good visual realism and a constant frame rate for natural scenes. PMID:25723177

  14. Use of an automated critical test result management system: effect on message delivery time.

    PubMed

    Gale, Brian D; Juran, David C

    2010-01-01

    Using an automated CTRM system in a radiology department leads to improved delivery of critical test results. Although a significant proportion of the improvement stems from experience, other factors likely contribute (eg, administrative support and acceptance by the medical staff). Longitudinal message documentation data was collected from 8 facilities. Data was evaluated to exclude the null hypothesis (absence of a relationship). CTRM experience (measured in days) was correlated with message delivery time (measured in hours). The goal was to evaluate the relationship between duration of experience and reduction in notification turnaround time (TAT).The inverse relationship of duration of experience with reduced TAT was highly significant, independent of other factors, even though experience only accounted for 25% of the improvement. PMID:22279720

  15. Finite Time Extinction for Stochastic Sign Fast Diffusion and Self-Organized Criticality

    NASA Astrophysics Data System (ADS)

    Gess, Benjamin

    2015-04-01

    We prove finite time extinction for stochastic sign fast diffusion equations driven by linear multiplicative space-time noise, corresponding to the Bak-Tang-Wiesenfeld model for self-organized criticality. This solves a problem posed and left open in several works: (Barbu, Methods Appl Sci 36:1726-1733, 2013; Röckner and Wang, J Lond Math Soc (2) 87:545-560, 2013; Barbu et al. J Math Anal Appl 389:147-164, 2012; Barbu and Röckner, Comm Math Phys 311:539-555, 2012; Barbu et al., Comm Math Phys 285:901-923, 2009, C R Math Acad Sci Paris 347(1-2):81-84, 2009). The highly singular-degenerate nature of the drift in interplay with the stochastic perturbation causes the need for new methods in the analysis of mass diffusion, and several new estimates and techniques are introduced.

  16. Does time reduce resistance to out-group critics? An investigation of the persistence of the intergroup sensitivity effect over time.

    PubMed

    Hiew, Danika N; Hornsey, Matthew J

    2010-09-01

    Group-directed criticism typically arouses greater defensiveness when it stems from an out-group member as opposed to an in-group member (the intergroup sensitivity effect). In light of work on the sleeper effect, the current research examines whether this defensiveness persists over time. Students received criticism of their faculty area from either a member of the same faculty area (in-group condition), or a member of a different faculty area (out-group condition), or they received no criticism (control condition). Despite relatively poor recall of the content of the criticism, the intergroup sensitivity effect (ISE) found immediately after presentation of the criticism had not significantly decreased 3-4 weeks later. However, the heightened intergroup bias found immediately after the out-group criticism did dissipate with time. Implications of these results for those who wish to initiate social change as outsiders are discussed. PMID:19849893

  17. Real-time data system: Incorporating new technology in mission critical environments

    NASA Technical Reports Server (NTRS)

    Muratore, John F.; Heindel, Troy A.

    1990-01-01

    If the Space Station Freedom is to remain viable over its 30-year life span, it must be able to incorporate new information systems technologies. These technologies are necessary to enhance mission effectiveness and to enable new NASA missions, such as supporting the Lunar-Mars Initiative. Hi-definition television (HDTV), neural nets, model-based reasoning, advanced languages, CPU designs, and computer networking standards are areas which have been forecasted to make major strides in the next 30 years. A major challenge to NASA is to bring these technologies online without compromising mission safety. In past programs, NASA managers have been understandably reluctant to rely on new technologies for mission critical activities until they are proven in noncritical areas. NASA must develop strategies to allow inflight confidence building and migration of technologies into the trusted tool base. NASA has successfully met this challenge and developed a winning strategy in the Space Shuttle Mission Control Center. This facility, which is clearly among NASA's most critical, is based on 1970's mainframe architecture. Changes to the mainframe are very expensive due to the extensive testing required to prove that changes do not have unanticipated impact on critical processes. Systematic improvement efforts in this facility have been delayed due to this 'risk to change.' In the real-time data system (RTDS) we have introduced a network of engineering computer workstations which run in parallel to the mainframe system. These workstations are located next to flight controller operating positions in mission control and, in some cases, the display units are mounted in the traditional mainframe consoles. This system incorporates several major improvements over the mainframe consoles including automated fault detection by real-time expert systems and color graphic animated schematics of subsystems driven by real-time telemetry. The workstations have the capability of recording

  18. Critical job events, acute stress, and strain: a multiple interrupted time series.

    PubMed

    Eden, D

    1982-12-01

    A critical job event (CJE) is defined as a time-bounded peak of performance demand made on the individual as an integral part of his job. Though such events are an important source of acute job stress and are amenable to longitudinal study, relevant research has been scant. In the present study, the effects of acute objective stress on subjective stress and on psychological and physiological strain were assessed among 39 first-year nursing students in an interrupted time series with multiple replications. Strain was measured five times, twice in anticipation of CJE interspersed by three low-stress occasions. The CJEs were providing the first comprehensive patient care and the final exam in nursing. A consistently confirmatory pattern of significantly rising and falling strain was found for anxiety, systolic blood pressure, and pulse rate: qualitative overload and serum uric acid changed as predicted four times out of five. CJE research can redress past overemphasis on chronic organizational stress and strengthen causal interpretation. PMID:10257633

  19. Actor-critic-based optimal tracking for partially unknown nonlinear discrete-time systems.

    PubMed

    Kiumarsi, Bahare; Lewis, Frank L

    2015-01-01

    This paper presents a partially model-free adaptive optimal control solution to the deterministic nonlinear discrete-time (DT) tracking control problem in the presence of input constraints. The tracking error dynamics and reference trajectory dynamics are first combined to form an augmented system. Then, a new discounted performance function based on the augmented system is presented for the optimal nonlinear tracking problem. In contrast to the standard solution, which finds the feedforward and feedback terms of the control input separately, the minimization of the proposed discounted performance function gives both feedback and feedforward parts of the control input simultaneously. This enables us to encode the input constraints into the optimization problem using a nonquadratic performance function. The DT tracking Bellman equation and tracking Hamilton-Jacobi-Bellman (HJB) are derived. An actor-critic-based reinforcement learning algorithm is used to learn the solution to the tracking HJB equation online without requiring knowledge of the system drift dynamics. That is, two neural networks (NNs), namely, actor NN and critic NN, are tuned online and simultaneously to generate the optimal bounded control policy. A simulation example is given to show the effectiveness of the proposed method. PMID:25312944

  20. Time-temperature-sensitization diagrams and critical cooling rates of different nitrogen containing austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Parvathavarthini, N.; Dayal, R. K.

    2010-04-01

    Nitrogen-alloyed 316L stainless steel is being used as structural material for high temperature fast breeder reactor components with a design life of 40 years. With a view to increase the design life to 60 years and beyond, high nitrogen stainless steels are being considered for certain critical components which may be used at high temperatures. Since carbon and nitrogen have major influence on the sensitization kinetics, investigations were carried out to establish the sensitization behaviour of four heats of 316L SS containing (i) 0.07%N and 0.035%C, (ii) 0.120%N and 0.030%C, (iii) 0.150%N and 0.025%C and (iv) 0.22%N and 0.035%C. These stainless steels were subjected to heat treatments in the temperature range of 823-1023 K for various durations ranging from 1 h to 500 h. Using ASTM standard A262 Practice A and E tests, time-temperature-sensitization diagrams were constructed and from these diagrams, critical cooling rate above which there is no risk of sensitization was calculated. The data established in this work can be used to select optimum heat treatment parameters during heat treatments of fabricated components for fast reactors.

  1. Tongue-Tie Assessment and Division: A Time-Critical Intervention to Optimise Breastfeeding

    PubMed Central

    Donati-Bourne, Jack; Batool, Zainab; Hendrickse, Charles; Bowley, Douglas

    2015-01-01

    Objectives: Recent reports have highlighted the benefits of surgical division of tongue-tie (frenulotomy) in infants with breastfeeding difficulties. There is no clear consensus defining the appropriate age for this procedure to be undertaken in selected infants. We aimed to evaluate the impact of delays in time between referral and frenulotomy in relation to maternal abandonment of breastfeeding. Materials and Methods: This was a prospective cohort study done in out-patient Neonatal Surgery Department, Birmingham Heartlands Hospital, Birmingham, UK, between April 2013 and July 2013. All infants, referred to our tongue-tie clinic between April and July 2013, were studied prospectively. Referral time lags were calculated using computer records; details regarding breastfeeding were collected by an independent interviewer completing a questionnaire. Results: Seventy patients were included. The median infant age at clinic was 28.5 days [range 1-126]. Fifty eight [82%] of mothers had breastfeeding difficulty and their infants were confirmed to have a prominent tongue-tie. By the time of their clinic attendance, breastfeeding had either not been established or abandoned in 21%. Despite difficulty, 61% of mothers persisted breastfeeding and all these mothers consented for frenulotomy. At time of clinic, median age of infants whose mothers had abandoned breastfeeding was 37 days [range 1-80] compared to 27 days [range 1-126] in infants whose mothers had persisted. Conclusions: We demonstrated a time-critical dimension for frenulotomy: delay beyond 4-weeks from referral to assessment of neonatal tongue-tie is more likely to be associated with abandonment of breastfeeding. Timely assessment and division of tongue-tie in selected infants can therefore play an important role in a birthing unit’s breastfeeding strategy. PMID:26023527

  2. Time-critical cooperative path-following control of multiple unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Xargay Mata, Enric

    This thesis addresses the problem of steering a fleet of unmanned aerial vehicles (UAVs) along desired 3D spatial paths while meeting stringent relative temporal constraints. A representative example is the challenging mission scenario where the UAVs are tasked to cooperatively execute collision-free maneuvers and arrive at their final destinations at the same time, or at different times so as to meet a desired inter-vehicle schedule. In the proposed framework, the UAVs are assigned nominal spatial paths and speed profiles along those, and then the vehicles are requested to execute cooperative path following, rather than "open-loop" trajectory-tracking maneuvers. This strategy yields robust behavior against external disturbances by allowing the UAVs to negotiate their speeds along the paths in response to information exchanged over a supporting inter-vehicle communications network. The proposed approach addresses explicitly the situation where each vehicle transmits coordination-relevant information to only a subset of the other vehicles, as determined by the time-varying communications topology. Furthermore, the thesis considers the case where the graph that captures the underlying communications topology is disconnected during some interval of time or even fails to be connected at all times. Conditions are given under which the complete time-critical cooperative path-following closed-loop system is stable and yields convergence of a conveniently defined cooperation error to a neighborhood of the origin. The thesis also derives lower bounds on the convergence rate of the coordination dynamics as a function of the quality of service of the supporting network, and proposes a coordination algorithm to improve the rate of convergence of the coordination dynamics in low-connectivity scenarios. Moreover, motivated by the exchange of information over networks with finite-rate communication links, the effect of quantization on vehicle coordination is also analyzed

  3. Infrared Sensor on Unmanned Aircraft Transmits Time-Critical Wildfire Data

    NASA Technical Reports Server (NTRS)

    Pestana, Mark

    2010-01-01

    Since 2006, NASA fs Dryden Flight Research Center (DFRC) and Ames Research Center have been perfecting and demonstrating a new capability for geolocation of wildfires and the real-time delivery of data to firefighters. Managed for the Western States Fire Mission, the Ames-developed Autonomous Modular Scanner (AMS), mounted beneath a wing of DFRC fs MQ-9 Ikhana remotely piloted aircraft, contains an infrared sensor capable of discriminating temperatures within 0.5 F (approx. = 0.3 C), up to 1,000 F (approx. = 540 C). The AMS operates like a digital camera with specialized filters to detect light energy at visible, infrared, and thermal wavelengths. By placing the AMS aboard unmanned aircraft, one can gather information and imaging for thousands of square miles, and provide critical information about the location, size, and terrain around fires to commanders in the field. In the hands of operational agencies, the benefits of this NASA research and development effort can support nationwide wildfire fighting efforts. The sensor also provides data for post-burn and vegetation regrowth analyses. The MQ-9 Unmanned Aircraft System (UAS), a version of the Predator-B, can operate over long distances, staying aloft for over 24 hours, and controlled via a satellite-linked command and control system. This same link is used to deliver the fire location data directly to fire incident commanders, in less than 10 minutes from the time of overflight. In the current method, similarly equipped short-duration manned aircraft, with limited endurance and range, must land, hand-carry, and process data, and then deliver information to the firefighters, sometimes taking several hours in the process. Meanwhile, many fires would have moved over great distances and changed direction. Speed is critical. The fire incident commanders must assess a very dynamic situation, and task resources such as people, ground equipment, and retardant-dropping aircraft, often in mountainous terrain obscured by

  4. Time-critical neurological emergencies: the unfulfilled role for point-of-care testing

    PubMed Central

    Knight, William A.; Clark, Joseph F.; Beyette, Fred R.; Pancioli, Arthur

    2010-01-01

    Background Neurological emergencies are common and frequently devastating. Every year, millions of Americans suffer an acute stroke, severe traumatic brain injury, subarachnoid hemorrhage, status epilepticus, or spinal cord injury severe enough to require medical intervention. Aims Full evaluation of the diseases in the acute setting often requires advanced diagnostics, and treatment frequently necessitates transfer to specialized centers. Delays in diagnosis and/or treatment may result in worsened outcomes; therefore, optimization of diagnostics is critical. Methods Point-of-care (POC) testing brings advanced diagnostics to the patient’s bedside in an effort to assist medical providers with real-time decisions based on real-time information. POC testing is usually associated with blood tests (blood glucose, troponin, etc.), but can involve imaging, medical devices, or adapting existing technologies for use outside of the hospital. Noticeably missing from the list of current point-of-care technologies are real-time bedside capabilities that address neurological emergencies. Results Unfortunately, the lack of these technologies may result in delayed identification of patients of these devastating conditions and contribute to less aggressive therapies than is seen with other disease processes. Development of time-dependent technologies appropriate for use with the neurologically ill patient are needed to improve therapies and outcomes. Conclusion POC-CENT is designed to support the development of novel ideas focused on improving diagnostic or prognostic capabilities for acute neurological emergencies. Eligible examples include biomarkers of traumatic brain injury, non-invasive measurements of intracranial pressure or cerebral vasospasm, and improved detection of pathological bacteria in suspected meningitis. PMID:20606822

  5. Analyzing the waiting time pattern for non-critical patients in the emergency department using six sigma approach

    NASA Astrophysics Data System (ADS)

    Majid, Noriza; Mohd Suradi, Nur Riza; Ahmad Sabri, Safura

    2013-04-01

    This study was conducted to examine the waiting time of non-critical patients in the Emergency Department (ED) of Universiti Kebangsaan Malaysia Medical Centre (UKMMC) using the approach of six sigma (6σ). The define phase is completed by obtaining customers' critical to quality in UKMMC using survey. In measure phase, data on patients to the ED of UKMMC in May 2009 were gathered. Subsequently, analysis phase is performed using cause-and-effect diagram to identify root causes of the problems. Finally, improvements are proposed based on the identified problems. Results show that waiting time is critical to quality for health services in the ED.

  6. [Organ transplantation in Germany: Critical examination in times of scarce resources].

    PubMed

    Haverich, A; Haller, H

    2016-01-01

    Organ transplantation over the last 40 years has developed into a standardized successful procedure for the replacement of heart, kidney liver, lung, and pancreas. During this time, treatment strategies have greatly improved and novel procedures such as living related organ donation have been introduced. Despite these improvements, the number of organ transplants has stalled in recent years. In the face of increasing numbers of patients on the waiting list for organ transplantation, this situation is unacceptable and ways to improve the situation of organ transplantation have to be found.The reasons for the stagnant situation in organ transplantation are manifold and include lack of awareness in the general population, insufficient organ procurement in hospitals as well as problems in organ allocation. The criteria for organ allocation have been unfairly reported to EUROTRANSPLANT by some of the presently 44 centers in order of more rapidly receive an organ for their patients on the waiting list. The evolving discussions around this so-called transplantation scandal has further eroded support for organ transplantation in Germany. A critical assessment and a well-defined plan are necessary to improve the situation, increase the number of transplanted organs, and reduce the unacceptably long waiting time for patients in Germany. PMID:26678283

  7. Real-time threat assessment for critical infrastructure protection: data incest and conflict in evidential reasoning

    NASA Astrophysics Data System (ADS)

    Brandon, R.; Page, S.; Varndell, J.

    2012-06-01

    This paper presents a novel application of Evidential Reasoning to Threat Assessment for critical infrastructure protection. A fusion algorithm based on the PCR5 Dezert-Smarandache fusion rule is proposed which fuses alerts generated by a vision-based behaviour analysis algorithm and a-priori watch-list intelligence data. The fusion algorithm produces a prioritised event list according to a user-defined set of event-type severity or priority weightings. Results generated from application of the algorithm to real data and Behaviour Analysis alerts captured at London's Heathrow Airport under the EU FP7 SAMURAI programme are presented. A web-based demonstrator system is also described which implements the fusion process in real-time. It is shown that this system significantly reduces the data deluge problem, and directs the user's attention to the most pertinent alerts, enhancing their Situational Awareness (SA). The end-user is also able to alter the perceived importance of different event types in real-time, allowing the system to adapt rapidly to changes in priorities as the situation evolves. One of the key challenges associated with fusing information deriving from intelligence data is the issue of Data Incest. Techniques for handling Data Incest within Evidential Reasoning frameworks are proposed, and comparisons are drawn with respect to Data Incest management techniques that are commonly employed within Bayesian fusion frameworks (e.g. Covariance Intersection). The challenges associated with simultaneously dealing with conflicting information and Data Incest in Evidential Reasoning frameworks are also discussed.

  8. Climatic and landscape controls on water transit times and silicate mineral weathering in the critical zone

    NASA Astrophysics Data System (ADS)

    Zapata-Rios, Xavier; McIntosh, Jennifer; Rademacher, Laura; Troch, Peter A.; Brooks, Paul D.; Rasmussen, Craig; Chorover, Jon

    2015-08-01

    The critical zone (CZ) can be conceptualized as an open system reactor that is continually transforming energy and water fluxes into an internal structural organization and dissipative products. In this study, we test a controlling factor on water transit times (WTT) and mineral weathering called Effective Energy and Mass Transfer (EEMT). We hypothesize that EEMT, quantified based on local climatic variables, can effectively predict WTT within—and mineral weathering products from—the CZ. This study tests whether EEMT or static landscape characteristics are good predictors of WTT, aqueous phase solutes, and silicate weathering products. Our study site is located around Redondo Peak, a rhyolitic volcanic resurgent dome, in northern New Mexico. At Redondo Peak, springs drain slopes along an energy gradient created by differences in terrain aspect. This investigation uses major solute concentrations, the calculated mineral mass undergoing dissolution, and the age tracer tritium and relates them quantitatively to EEMT and landscape characteristics. We found significant correlations between EEMT, WTT, and mineral weathering products. Significant correlations were observed between dissolved weathering products (Na+ and DIC), 3H concentrations, and maximum EEMT. In contrast, landscape characteristics such as contributing area of spring, slope gradient, elevation, and flow path length were not as effective predictive variables of WTT, solute concentrations, and mineral weathering products. These results highlight the interrelationship between landscape, hydrological, and biogeochemical processes and suggest that basic climatic data embodied in EEMT can be used to scale hydrological and hydrochemical responses in other sites.

  9. Critical space-time networks and geometric phase transitions from frustrated edge antiferromagnetism.

    PubMed

    Trugenberger, Carlo A

    2015-12-01

    Recently I proposed a simple dynamical network model for discrete space-time that self-organizes as a graph with Hausdorff dimension d(H)=4. The model has a geometric quantum phase transition with disorder parameter (d(H)-d(s)), where d(s) is the spectral dimension of the dynamical graph. Self-organization in this network model is based on a competition between a ferromagnetic Ising model for vertices and an antiferromagnetic Ising model for edges. In this paper I solve a toy version of this model defined on a bipartite graph in the mean-field approximation. I show that the geometric phase transition corresponds exactly to the antiferromagnetic transition for edges, the dimensional disorder parameter of the former being mapped to the staggered magnetization order parameter of the latter. The model has a critical point with long-range correlations between edges, where a continuum random geometry can be defined, exactly as in Kazakov's famed 2D random lattice Ising model but now in any number of dimensions. PMID:26764755

  10. Broadcast-quality-stereoscopic video in a time-critical entertainment and corporate environment

    NASA Astrophysics Data System (ADS)

    Gay, Jean-Philippe

    1995-03-01

    `reality present: Peter Gabrial and Cirque du Soleil' is a 12 minute original work directed and produced by Doug Brown, Jean-Philippe Gay & A. Coogan, which showcases creative content applications of commercial stereoscopic video equipment. For production, a complete equipment package including a Steadicam mount was used in support of the Ikegami LK-33 camera. Remote production units were fielded in the time critical, on-stage and off-stage environments of 2 major live concerts: Peter Gabriel's Secret World performance at the San Diego Sports Arena, and Cirque du Soleil's Saltimbanco performance in Chicago. Twin 60 Hz video channels were captured on Beta SP for maximum post production flexibility. Digital post production and field sequential mastering were effected in D-2 format at studio facilities in Los Angeles. The program was world premiered to a large public at the World of Music, Arts and Dance festivals in Los Angeles and San Francisco, in late 1993. It was presented to the artists in Los Angeles, Montreal and Washington D.C. Additional presentations have been made using a broad range of commercial and experimental stereoscopic video equipment, including projection systems, LCD and passive eyewear, and digital signal processors. Technical packages for live presentation have been fielded on site and off, through to the present.

  11. Critical space-time networks and geometric phase transitions from frustrated edge antiferromagnetism

    NASA Astrophysics Data System (ADS)

    Trugenberger, Carlo A.

    2015-12-01

    Recently I proposed a simple dynamical network model for discrete space-time that self-organizes as a graph with Hausdorff dimension dH=4 . The model has a geometric quantum phase transition with disorder parameter (dH-ds) , where ds is the spectral dimension of the dynamical graph. Self-organization in this network model is based on a competition between a ferromagnetic Ising model for vertices and an antiferromagnetic Ising model for edges. In this paper I solve a toy version of this model defined on a bipartite graph in the mean-field approximation. I show that the geometric phase transition corresponds exactly to the antiferromagnetic transition for edges, the dimensional disorder parameter of the former being mapped to the staggered magnetization order parameter of the latter. The model has a critical point with long-range correlations between edges, where a continuum random geometry can be defined, exactly as in Kazakov's famed 2D random lattice Ising model but now in any number of dimensions.

  12. Hospitalizations, Costs, and Mortality among Infants with Critical Congenital Heart Disease: How Important Is Timely Detection?

    PubMed Central

    Peterson, Cora; Dawson, April; Grosse, Scott D.; Riehle-Colarusso, Tiffany; Olney, Richard S.; Tanner, Jean Paul; Kirby, Russell S.; Correia, Jane A.; Watkins, Sharon M.; Cassell, Cynthia H.

    2015-01-01

    BACKGROUND Critical congenital heart disease (CCHD) was recently added to the U.S. Recommended Uniform Screening Panel for newborns. States considering screening requirements may want more information about the potential impact of screening. This study examined potentially avoidable mortality among infants with late detected CCHD and assessed whether late detection was associated with increased hospital resource use during infancy. METHODS This was a state-wide, population-based, observational study of infants with CCHD (n =3603) born 1998 to 2007 identified by the Florida Birth Defects Registry. We examined 12 CCHD conditions that are targets of newborn screening. Late detection was defined as CCHD diagnosis after the birth hospitalization. Deaths potentially avoidable through screening were defined as those that occurred outside a hospital following birth hospitalization discharge and those that occurred within 3 days of an emergency readmission. RESULTS For 23% (n =825) of infants, CCHD was not detected during the birth hospitalization. Death occurred among 20% (n =568/2,778) of infants with timely detected CCHD and 8% (n =66/825) of infants with late detected CCHD, unadjusted for clinical characteristics. Potentially preventable deaths occurred in 1.8% (n =15/825) of infants with late detected CCHD (0.4% of all infants with CCHD). In multivariable models adjusted for selected characteristics, late CCHD detection was significantly associated with 52% more admissions, 18% more hospitalized days, and 35% higher inpatient costs during infancy. CONCLUSION Increased CCHD detection at birth hospitals through screening may lead to decreased hospital costs and avoid some deaths during infancy. Additional studies conducted after screening implementation are needed to confirm these findings. PMID:24000201

  13. Real time evolution of non-Gaussian cumulants in the QCD critical regime

    DOE PAGESBeta

    Mukherjee, Swagato; Venugopalan, Raju; Yin, Yi

    2015-09-23

    In this study, we derive a coupled set of equations that describe the nonequilibrium evolution of cumulants of critical fluctuations for spacetime trajectories on the crossover side of the QCD phase diagram. In particular, novel expressions are obtained for the nonequilibrium evolution of non-Gaussian skewness and kurtosis cumulants. UBy utilizing a simple model of the spacetime evolution of a heavy-ion collision, we demonstrate that, depending on the relaxation rate of critical fluctuations, skewness and kurtosis can differ significantly in magnitude as well as in sign from equilibrium expectations. Memory effects are important and shown to persist even for trajectories thatmore » skirt the edge of the critical regime. We use phenomenologically motivated parametrizations of freeze-out curves and of the beam-energy dependence of the net baryon chemical potential to explore the implications of our model study for the critical-point search in heavy-ion collisions.« less

  14. Real time evolution of non-Gaussian cumulants in the QCD critical regime

    SciTech Connect

    Mukherjee, Swagato; Venugopalan, Raju; Yin, Yi

    2015-09-23

    In this study, we derive a coupled set of equations that describe the nonequilibrium evolution of cumulants of critical fluctuations for spacetime trajectories on the crossover side of the QCD phase diagram. In particular, novel expressions are obtained for the nonequilibrium evolution of non-Gaussian skewness and kurtosis cumulants. UBy utilizing a simple model of the spacetime evolution of a heavy-ion collision, we demonstrate that, depending on the relaxation rate of critical fluctuations, skewness and kurtosis can differ significantly in magnitude as well as in sign from equilibrium expectations. Memory effects are important and shown to persist even for trajectories that skirt the edge of the critical regime. We use phenomenologically motivated parametrizations of freeze-out curves and of the beam-energy dependence of the net baryon chemical potential to explore the implications of our model study for the critical-point search in heavy-ion collisions.

  15. CPFPS: Development of a Safety Critical Hard Real Time Distributed Application for EGNOS

    NASA Astrophysics Data System (ADS)

    Campos, J.; Mora, E.; Zarraoa, N.

    EGNOS is a satellite and ground based system that augments the existing satellite navigation services provided by the American Global Positioning System (GPS) and the Russian Global Navigation Satellite System (GLONASS). CPFPS (Central Processing Facility Processing Set), the core of EGNOS, is the application in charge of computing the EGNOS messages. CPFPS is a safety critical hard real time distributed application of 120 KLOC of source code. This paper describes the challenges of the CPFPS requirements and the decisions in terms of processes, methods, tools and design put into practice for the successful implementation of CPFPS. 2.- EGNOS and the CPFPS EGNOS is a satellite and ground based system that augments the existing satellite navigation services provided by the American Global Positioning System (GPS) and the Russian Global Navigation Satellite System (GLONASS) for those users who are equipped with an appropriate receiver. The EGNOS System is defined around four Segments: • A Ground Segment that determines integrity and error correction message, which includes a network of RIMS (Ranging Integrity Monitoring Station), a set of redundant control and processing facilities called MCC (Master Control Center), and a set of NLES (Navigation Land Earth Station). All these elements are connected through the EWAN (EGNOS Wide Area Network). Each MCC contains a CPF. • A Space Segment based on Geostationary satellites (GEO) which provides the Signal In Space (SIS). • A User Segment which supports the navigation service using the GEO SIS, GPS and GLONASS signals. • A Support Segment, which includes facilities necessary to support the operational System (from its development to its operations). The GPS, GLONASS and GEO data are collected at widely dispersed sites by RIMS. These data are forwarded to CPF. Each EGNOS message is sent to the NLES to be up-linked to EGNOS GEO satellites for onward transmission to the users. There are several redundant CPF to achieve

  16. Time to Look Anew: Critical Pedagogy and Disciplines within Higher Education

    ERIC Educational Resources Information Center

    McArthur, Jan

    2010-01-01

    This article explores the attitudes of writers within the tradition of critical pedagogy towards disciplines in higher education. With particular focus on Henry Giroux's work, it contrasts his portrayal of disciplines as closed, limiting and elitist with an alternative one of disciplines as complex, permeable and contested spaces. Critical…

  17. Critical Pedagogy in Uncertain Times: Hope and Possibilities. Education, Politics and Public Life

    ERIC Educational Resources Information Center

    Macrine, Sheila L., Ed.

    2012-01-01

    This book provides comprehensive analyses of issues related to the struggle against the forces of imperial-induced privatization, not just in education, but in all of social life. It situates Critical Pedagogy in the twenty-first century and offers not only critiques but also practical applications, suggestions, and strategies on how attacks can…

  18. Designing for Temporal Awareness: The Role of Temporality in Time-Critical Medical Teamwork

    PubMed Central

    Kusunoki, Diana S.; Sarcevic, Aleksandra

    2016-01-01

    This paper describes the role of temporal information in emergency medical teamwork and how time-based features can be designed to support the temporal awareness of clinicians in this fast-paced and dynamic environment. Engagement in iterative design activities with clinicians over the course of two years revealed a strong need for time-based features and mechanisms, including timestamps for tasks based on absolute time and automatic stopclocks measuring time by counting up since task performance. We describe in detail the aspects of temporal awareness central to clinicians’ awareness needs and then provide examples of how we addressed these needs through the design of a shared information display. As an outcome of this process, we define four types of time representation techniques to facilitate the design of time-based features: (1) timestamps based on absolute time, (2) timestamps relative to the process start time, (3) time since task performance, and (4) time until the next required task. PMID:27478880

  19. The Infeasibility of Quantifying the Reliability of Life-Critical Real-Time Software

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.; Finelli, George B.

    1991-01-01

    This paper affirms that the quantification of life-critical software reliability is infeasible using statistical methods whether applied to standard software or fault-tolerant software. The classical methods of estimating reliability are shown to lead to exhorbitant amounts of testing when applied to life-critical software. Reliability growth models are examined and also shown to be incapable of overcoming the need for excessive amounts of testing. The key assumption of software fault tolerance separately programmed versions fail independently is shown to be problematic. This assumption cannot be justified by experimentation in the ultrareliability region and subjective arguments in its favor are not sufficiently strong to justify it as an axiom. Also, the implications of the recent multiversion software experiments support this affirmation.

  20. The infeasibility of quantifying the reliability of life-critical real-time software

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.; Finelli, George B.

    1993-01-01

    This paper affirms that the quantification of life-critical software reliability is infeasible using statistical methods, whether these methods are applied to standard software or fault-tolerant software. The classical methods of estimating reliability are shown to lead to exorbitant amounts of testing when applied to life-critical software. Reliability growth models are examined and also shown to be incapable of overcoming the need for excessive amounts of testing. The key assumption of software fault tolerance - separately programmed versions fail independently - is shown to be problematic. This assumption cannot be justified by experimentation in the ultrareliability region, and subjective arguments in its favor are not sufficiently strong to justify it as an axiom. Also, the implications of the recent multiversion software experiments support this affirmation.

  1. Multi-Step Ahead Predictions for Critical Levels in Physiological Time Series.

    PubMed

    ElMoaqet, Hisham; Tilbury, Dawn M; Ramachandran, Satya Krishna

    2016-07-01

    Standard modeling and evaluation methods have been classically used in analyzing engineering dynamical systems where the fundamental problem is to minimize the (mean) error between the real and predicted systems. Although these methods have been applied to multi-step ahead predictions of physiological signals, it is often more important to predict clinically relevant events than just to match these signals. Adverse clinical events, which occur after a physiological signal breaches a clinically defined critical threshold, are a popular class of such events. This paper presents a framework for multi-step ahead predictions of critical levels of abnormality in physiological signals. First, a performance metric is presented for evaluating multi-step ahead predictions. Then, this metric is used to identify personalized models optimized with respect to predictions of critical levels of abnormality. To address the paucity of adverse events, weighted support vector machines and cost-sensitive learning are used to optimize the proposed framework with respect to statistical metrics that can take into account the relative rarity of such events. PMID:27244754

  2. Multiple actor-critic structures for continuous-time optimal control using input-output data.

    PubMed

    Song, Ruizhuo; Lewis, Frank; Wei, Qinglai; Zhang, Hua-Guang; Jiang, Zhong-Ping; Levine, Dan

    2015-04-01

    In industrial process control, there may be multiple performance objectives, depending on salient features of the input-output data. Aiming at this situation, this paper proposes multiple actor-critic structures to obtain the optimal control via input-output data for unknown nonlinear systems. The shunting inhibitory artificial neural network (SIANN) is used to classify the input-output data into one of several categories. Different performance measure functions may be defined for disparate categories. The approximate dynamic programming algorithm, which contains model module, critic network, and action network, is used to establish the optimal control in each category. A recurrent neural network (RNN) model is used to reconstruct the unknown system dynamics using input-output data. NNs are used to approximate the critic and action networks, respectively. It is proven that the model error and the closed unknown system are uniformly ultimately bounded. Simulation results demonstrate the performance of the proposed optimal control scheme for the unknown nonlinear system. PMID:25730830

  3. CoR-MAC: Contention over Reservation MAC Protocol for Time-Critical Services in Wireless Body Area Sensor Networks.

    PubMed

    Yu, Jeongseok; Park, Laihyuk; Park, Junho; Cho, Sungrae; Keum, Changsup

    2016-01-01

    Reserving time slots for urgent data, such as life-critical information, seems to be very attractive to guarantee their deadline requirements in wireless body area sensor networks (WBASNs). On the other hand, this reservation imposes a negative impact on performance for the utilization of a channel. This paper proposes a new channel access scheme referred to as the contention over reservation MAC (CoR-MAC) protocol for time-critical services in wireless body area sensor networks. CoR-MAC uses the dual reservation; if the reserved time slots are known to be vacant, other nodes can access the time slots by contention-based reservation to maximize the utilization of a channel and decrease the delay of the data. To measure the effectiveness of the proposed scheme against IEEE 802.15.4 and IEEE 802.15.6, we evaluated their performances with various performance indexes. The CoR-MAC showed 50% to 850% performance improvement in terms of the delay of urgent and time-critical data according to the number of nodes. PMID:27171085

  4. CoR-MAC: Contention over Reservation MAC Protocol for Time-Critical Services in Wireless Body Area Sensor Networks

    PubMed Central

    Yu, Jeongseok; Park, Laihyuk; Park, Junho; Cho, Sungrae; Keum, Changsup

    2016-01-01

    Reserving time slots for urgent data, such as life-critical information, seems to be very attractive to guarantee their deadline requirements in wireless body area sensor networks (WBASNs). On the other hand, this reservation imposes a negative impact on performance for the utilization of a channel. This paper proposes a new channel access scheme referred to as the contention over reservation MAC (CoR-MAC) protocol for time-critical services in wireless body area sensor networks. CoR-MAC uses the dual reservation; if the reserved time slots are known to be vacant, other nodes can access the time slots by contention-based reservation to maximize the utilization of a channel and decrease the delay of the data. To measure the effectiveness of the proposed scheme against IEEE 802.15.4 and IEEE 802.15.6, we evaluated their performances with various performance indexes. The CoR-MAC showed 50% to 850% performance improvement in terms of the delay of urgent and time-critical data according to the number of nodes. PMID:27171085

  5. Measuring social integration in a pilot randomized controlled trial of critical time: intervention-task shifting in Latin America

    PubMed Central

    Baumgartner, Joy Noel; da Silva, Tatiana Fernandes Carpinteiro; Valencia, Eliecer; Susser, Ezra

    2013-01-01

    Global mental health movements increasingly highlight the importance of social integration for individuals living with severe mental illnesses. However, this important individual-level outcome is rarely measured in programs. As part of RedeAmericas, a pilot regional randomized controlled trial of critical time intervention — task shifting — will be conducted, which includes social integration as an outcome measure. It is a time-limited care coordination model to enhance continuity of support for people with severe mental illness during critical periods of transition. Given the challenges of measuring social integration, particularly for a multi-country study with unique cultural contexts, this paper has described the measurement approach used to create a composite measure that uses items from disability and quality of life instruments in addition to other key items. PMID:24288454

  6. Measuring social integration in a pilot randomized controlled trial of critical time: intervention-task shifting in Latin America.

    PubMed

    Baumgartner, Joy Noel; da Silva, Tatiana Fernandes Carpinteiro; Valencia, Eliecer; Susser, Ezra

    2012-01-01

    Global mental health movements increasingly highlight the importance of social integration for individuals living with severe mental illnesses. However, this important individual-level outcome is rarely measured in programs. As part of RedeAmericas, a pilot regional randomized controlled trial of critical time intervention - task shifting - will be conducted, which includes social integration as an outcome measure. It is a time-limited care coordination model to enhance continuity of support for people with severe mental illness during critical periods of transition. Given the challenges of measuring social integration, particularly for a multi-country study with unique cultural contexts, this paper has described the measurement approach used to create a composite measure that uses items from disability and quality of life instruments in addition to other key items. PMID:24288454

  7. Real-Time Monitoring of Critical Care Analytes in the Bloodstream with Chemical Sensors: Progress and Challenges

    NASA Astrophysics Data System (ADS)

    Frost, Megan C.; Meyerhoff, Mark E.

    2015-07-01

    We review approaches and challenges in developing chemical sensor-based methods to accurately and continuously monitor levels of key analytes in blood related directly to the status of critically ill hospitalized patients. Electrochemical and optical sensor-based technologies have been pursued to measure important critical care species in blood [i.e., oxygen, carbon dioxide, pH, electrolytes (K+, Na+, Cl-, etc.), glucose, and lactate] in real-time or near real-time. The two main configurations examined to date for achieving this goal have been intravascular catheter sensors and patient attached ex vivo sensors with intermittent blood sampling via an attached indwelling catheter. We discuss the status of these configurations and the main issues affecting the accuracy of the measurements, including cell adhesion and thrombus formation on the surface of the sensors, sensor drift, sensor selectivity, etc. Recent approaches to mitigate these nagging performance issues that have prevented these technologies from clinical use are also discussed.

  8. Critical evaluation of attosecond time delays retrieved from photoelectron streaking measurements

    NASA Astrophysics Data System (ADS)

    Wei, Hui; Morishita, Toru; Lin, C. D.

    2016-05-01

    A photoelectron streaking experiment which was conceived as a means to extract the electron wave packet of single-photon ionization has also been employed to retrieve time delays in the fundamental photoemission processes. The discrepancies between the time delays thus measured and those from many sophisticated theoretical calculations have generated a great deal of controversy in recent years. Here we present a careful examination of the methods that were used to retrieve the time delays and demonstrate the difficulty of achieving an accuracy of the retrieved time delays of a few to tens of attoseconds in typical streaking measurements. The difficulty owes more to the lower sensitivity of the streaking spectra to the phase of the photoionization transition dipole than to the spectral phase of the attosecond light pulse in the experiment. The retrieved time delay contains extra errors when the attochirp of the attosecond pulse is large so that the dipole phase becomes negligible compared to it.

  9. Reliable real-time calculation of heart-rate complexity in critically ill patients using multiple noisy waveform sources.

    PubMed

    Liu, Nehemiah T; Cancio, Leopoldo C; Salinas, Jose; Batchinsky, Andriy I

    2014-04-01

    Heart-rate complexity (HRC) has been proposed as a new vital sign for critical care medicine. The purpose of this research was to develop a reliable method for determining HRC continuously in real time in critically ill patients using multiple waveform channels that also compensates for noisy and unreliable data. Using simultaneously acquired electrocardiogram (Leads I, II, V) and arterial blood pressure waveforms sampled at 360 Hz from 250 patients (over 375 h of patient data), we evaluated a new data fusion framework for computing HRC in real time. The framework employs two algorithms as well as signal quality indices. HRC was calculated (via the method of sample entropy), and equivalence tests were then performed. Bland-Altman plots and box plots of differences between mean HRC values were also obtained. Finally, HRC differences were analyzed by paired t tests. The gold standard for obtaining true means was manual verification of R waves and subsequent entropy calculations. Equivalence tests between mean HRC values derived from manually verified sequences and those derived from automatically detected peaks showed that the "Fusion" values were the least statistically different from the gold standard. Furthermore, the fusion of waveform sources produced better error density distributions than those derived from individual waveforms. The data fusion framework was shown to provide in real-time a reliable continuously streamed HRC value, derived from multiple waveforms in the presence of noise and artifacts. This approach will be validated and tested for assessment of HRC in critically ill patients. PMID:23990286

  10. Use of Peer Staff in a Critical Time Intervention for Frequent Users of a Psychiatric Emergency Room.

    PubMed

    Nossel, Ilana R; Lee, Rufina J; Isaacs, Abby; Herman, Daniel B; Marcus, Sue M; Essock, Susan M

    2016-05-01

    Project Connect, a clinical demonstration program developed in consultation with the New York State Office of Mental Health, adapted critical time intervention for frequent users of a large urban psychiatric emergency room (ER). Peer staff provided frequent users with time-limited care coordination. Participants increased their use of outpatient services over 12 months, compared with a similar group not enrolled in the program. For persons with significant general medical, psychiatric, and social needs, provision of this intervention alone is unlikely to reduce reliance on ERs, especially among homeless individuals. PMID:26766759

  11. Criticality and long-range correlations in time series in classical and quantum systems.

    PubMed

    Landa, E; Morales, Irving O; Fossion, R; Stránský, P; Velázquez, V; Vieyra, J C López; Frank, A

    2011-07-01

    We present arguments which indicate that a transitional state in between two different regimes implies the occurrence of 1/f time series and that this property is generic in both classical and quantum systems. Our study focuses on two particular examples: the one-dimensional module-1 logistic map and nuclear excitation spectra obtained with a schematic shell-model Hamiltonian. We suggest that a transitional point is characterized by the long-range correlations implied by 1/f time series. We apply a Fourier spectral analysis and the detrended fluctuation analysis method to study the fluctuations to each system. PMID:21867290

  12. Criticality and long-range correlations in time series in classical and quantum systems

    NASA Astrophysics Data System (ADS)

    Landa, E.; Morales, Irving O.; Fossion, R.; Stránský, P.; Velázquez, V.; López Vieyra, J. C.; Frank, A.

    2011-07-01

    We present arguments which indicate that a transitional state in between two different regimes implies the occurrence of 1/f time series and that this property is generic in both classical and quantum systems. Our study focuses on two particular examples: the one-dimensional module-1 logistic map and nuclear excitation spectra obtained with a schematic shell-model Hamiltonian. We suggest that a transitional point is characterized by the long-range correlations implied by 1/f time series. We apply a Fourier spectral analysis and the detrended fluctuation analysis method to study the fluctuations to each system.

  13. Adaptive critic designs for discrete-time zero-sum games with application to H(infinity) control.

    PubMed

    Al-Tamimi, Asma; Abu-Khalaf, Murad; Lewis, Frank L

    2007-02-01

    In this correspondence, adaptive critic approximate dynamic programming designs are derived to solve the discrete-time zero-sum game in which the state and action spaces are continuous. This results in a forward-in-time reinforcement learning algorithm that converges to the Nash equilibrium of the corresponding zero-sum game. The results in this correspondence can be thought of as a way to solve the Riccati equation of the well-known discrete-time H(infinity) optimal control problem forward in time. Two schemes are presented, namely: 1) a heuristic dynamic programming and 2) a dual-heuristic dynamic programming, to solve for the value function and the costate of the game, respectively. An H(infinity) autopilot design for an F-16 aircraft is presented to illustrate the results. PMID:17278575

  14. A conceptual model for evolving run time support of mission and safety critical components in large, complex, distributed systems

    NASA Technical Reports Server (NTRS)

    Mckay, Charles W.

    1988-01-01

    Large, complex, distributed systems should be evolved to maximize life cycle support for non-stop operation of mission and safety critical components. This paper outlines the key issues and a recommended approach for tailoring a conceptual model of Ada run time support environments to meet the specific needs of such an application. Prerequisite concepts for this model have been described previously by this author and are summarized. This model proposes upward-compatible extensions to a previously published model of Ada run time environments from the ARTEWG (Ada Run Time Environment Working Group). The first model was used to identify Ada run time requirements, dependencies, issues, features, and options for single processor applications; however, the particular needs for distributed processing were not explicitly described. The purpose of this extended model is to address the needed systems software support for Ada application programs in distributed computing environments.

  15. Eye Colour and Reaction Time: An Opportunity for Critical Statistical Reasoning

    ERIC Educational Resources Information Center

    Watson, Jane

    2008-01-01

    This author was surprised to read a short article in "The Mercury" newspaper in Hobart about blue-eyed people being more intelligent and brown-eyed people having faster reaction times. Such an article invites immediate scepticism from the statistically literate. The lack of data in the article should lead the interested reader to a search for…

  16. A Paradox within the Time Value of Money: A Critical Thinking Exercise for Finance Students

    ERIC Educational Resources Information Center

    Delaney, Charles J.; Rich, Steven P.; Rose, John T.

    2016-01-01

    This study presents a paradox within the time value of money (TVM), namely, that the interest-principal sequence embedded in the payment stream of an amortized loan is exactly the opposite of the interest-principal sequence implicit in the present value of a matching annuity. We examine this inverse sequence, both mathematically and intuitively,…

  17. Moments of action provide insight into critical times for advection-diffusion-reaction processes

    NASA Astrophysics Data System (ADS)

    Ellery, Adam J.; Simpson, Matthew J.; McCue, Scott W.; Baker, Ruth E.

    2012-09-01

    Berezhkovskii and co-workers introduced the concept of local accumulation time as a finite measure of the time required for the transient solution of a reaction-diffusion equation to effectively reach steady state [Biophys J.BIOJAU0006-349510.1016/j.bpj.2010.07.045 99, L59 (2010); Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.83.051906 83, 051906 (2011)]. Berezhkovskii's approach is a particular application of the concept of mean action time (MAT) that was introduced previously by McNabb [IMA J. Appl. Math.IJAMDM0272-496010.1093/imamat/47.2.193 47, 193 (1991)]. Here, we generalize these previous results by presenting a framework to calculate the MAT, as well as the higher moments, which we call the moments of action. The second moment is the variance of action time, the third moment is related to the skew of action time, and so on. We consider a general transition from some initial condition to an associated steady state for a one-dimensional linear advection-diffusion-reaction partial differential equation (PDE). Our results indicate that it is possible to solve for the moments of action exactly without requiring the transient solution of the PDE. We present specific examples that highlight potential weaknesses of previous studies that have considered the MAT alone without considering higher moments. Finally, we also provide a meaningful interpretation of the moments of action by presenting simulation results from a discrete random-walk model together with some analysis of the particle lifetime distribution. This work shows that the moments of action are identical to the moments of the particle lifetime distribution for certain transitions.

  18. Is it time to drop the ‘knowledge translation’ metaphor? A critical literature review

    PubMed Central

    Greenhalgh, Trisha; Wieringa, Sietse

    2011-01-01

    The literature on ‘knowledge translation’ presents challenges for the reviewer because different terms have been used to describe the generation, sharing and application of knowledge and different research approaches embrace different philosophical positions on what knowledge is. We present a narrative review of this literature which deliberately sought to highlight rather than resolve tensions between these different framings. Our findings suggest that while ‘translation’ is a widely used metaphor in medicine, it constrains how we conceptualise and study the link between knowledge and practice. The ‘translation’ metaphor has, arguably, led to particular difficulties in the fields of ‘evidence-based management’ and ‘evidence-based policymaking’ – where it seems that knowledge obstinately refuses to be driven unproblematically into practice. Many non-medical disciplines such as philosophy, sociology and organization science conceptualise knowledge very differently, as being (for example) ‘created’, ‘constructed’, ‘embodied’, ‘performed’ and ‘collectively negotiated’ – and also as being value-laden and tending to serve the vested interests of dominant élites. We propose that applying this wider range of metaphors and models would allow us to research the link between knowledge and practice in more creative and critical ways. We conclude that research should move beyond a narrow focus on the ‘know–do gap’ to cover a richer agenda, including: (a) the situation-specific practical wisdom (phronesis) that underpins clinical judgement; (b) the tacit knowledge that is built and shared among practitioners (‘mindlines’); (c) the complex links between power and knowledge; and (d) approaches to facilitating macro-level knowledge partnerships between researchers, practitioners, policymakers and commercial interests. PMID:22179293

  19. Health Monitor for Multitasking, Safety-Critical, Real-Time Software

    NASA Technical Reports Server (NTRS)

    Zoerner, Roger

    2011-01-01

    Health Manager can detect Bad Health prior to a failure occurring by periodically monitoring the application software by looking for code corruption errors, and sanity-checking each critical data value prior to use. A processor s memory can fail and corrupt the software, or the software can accidentally write to the wrong address and overwrite the executing software. This innovation will continuously calculate a checksum of the software load to detect corrupted code. This will allow a system to detect a failure before it happens. This innovation monitors each software task (thread) so that if any task reports "bad health," or does not report to the Health Manager, the system is declared bad. The Health Manager reports overall system health to the outside world by outputting a square wave signal. If the square wave stops, this indicates that system health is bad or hung and cannot report. Either way, "bad health" can be detected, whether caused by an error, corrupted data, or a hung processor. A separate Health Monitor Task is started and run periodically in a loop that starts and stops pending on a semaphore. Each monitored task registers with the Health Manager, which maintains a count for the task. The registering task must indicate if it will run more or less often than the Health Manager. If the task runs more often than the Health Manager, the monitored task calls a health function that increments the count and verifies it did not go over max-count. When the periodic Health Manager runs, it verifies that the count did not go over the max-count and zeroes it. If the task runs less often than the Health Manager, the periodic Health Manager will increment the count. The monitored task zeroes the count, and both the Health Manager and monitored task verify that the count did not go over the max-count.

  20. CA1 neurons in the human hippocampus are critical for autobiographical memory, mental time travel, and autonoetic consciousness

    PubMed Central

    Bartsch, Thorsten; Döhring, Juliane; Rohr, Axel; Jansen, Olav; Deuschl, Günther

    2011-01-01

    Autobiographical memories in our lives are critically dependent on temporal lobe structures. However, the contribution of CA1 neurons in the human hippocampus to the retrieval of episodic autobiographical memory remains elusive. In patients with a rare acute transient global amnesia, highly focal lesions confined to the CA1 field of the hippocampus can be detected on MRI. We studied the effect of these lesions on autobiographical memory using a detailed autobiographical interview including the remember/know procedure. In 14 of 16 patients, focal lesions in the CA1 sector of the hippocampal cornu ammonis were detected. Autobiographical memory was significantly affected over all time periods, including memory for remote periods. Impairment of episodic memory and autonoetic consciousness exhibited a strong temporal gradient extending 30 to 40 y into the past. These results highlight the distinct and critical role of human hippocampal CA1 neurons in autobiographical memory retrieval and for re-experiencing detailed episodic memories. PMID:21987814

  1. Bound on quantum computation time: Quantum error correction in a critical environment

    SciTech Connect

    Novais, E.; Mucciolo, Eduardo R.; Baranger, Harold U.

    2010-08-15

    We obtain an upper bound on the time available for quantum computation for a given quantum computer and decohering environment with quantum error correction implemented. First, we derive an explicit quantum evolution operator for the logical qubits and show that it has the same form as that for the physical qubits but with a reduced coupling strength to the environment. Using this evolution operator, we find the trace distance between the real and ideal states of the logical qubits in two cases. For a super-Ohmic bath, the trace distance saturates, while for Ohmic or sub-Ohmic baths, there is a finite time before the trace distance exceeds a value set by the user.

  2. Incidental nutrient transfers: Assessing critical times in agricultural catchments using high-resolution data.

    PubMed

    Shore, Mairead; Jordan, Phil; Melland, Alice R; Mellander, Per-Erik; McDonald, Noeleen; Shortle, Ger

    2016-05-15

    Managing incidental losses associated with liquid slurry applications during closed periods has significant cost and policy implications and the environmental data required to review such a measure are difficult to capture due to storm dependencies. Over four years (2010-2014) in five intensive agricultural catchments, this study used high-resolution total and total reactive phosphorus (TP and TRP), total oxidised nitrogen (TON) and suspended sediment (SS) concentrations with river discharge data to investigate the magnitude and timing of nutrient losses. A large dataset of storm events (defined as 90th percentile discharges), and associated flow-weighted mean (FWM) nutrient concentrations and TP/SS ratios, was used to indicate when losses were indicative of residual or incidental nutrient transfers. The beginning of the slurry closed period was reflective of incidental and residual transfers with high storm FWM P (TP and TRP) concentrations, with some catchments also showing elevated storm TP:SS ratios. This pattern diminished at the end of the closed period in all catchments. Total oxidised N behaved similarly to P during storms in the poorly drained catchments and revealed a long lag time in other catchments. Low storm FWM P concentrations and TP:SS ratios during the weeks following the closed period suggests that nutrients either weren't applied during this time (best times chosen) or that they were applied to less risky areas (best places chosen). For other periods such as late autumn and during wet summers, where storm FWM P concentrations and TP:SS ratios were high, it is recommended that an augmentation of farmer knowledge of soil drainage characteristics with local and detailed current and forecast soil moisture conditions will help to strengthen existing regulatory frameworks to avoid storm driven incidental nutrient transfers. PMID:26933967

  3. Task-oriented quality assessment and adaptation in real-time mission critical video streaming applications

    NASA Astrophysics Data System (ADS)

    Nightingale, James; Wang, Qi; Grecos, Christos

    2015-02-01

    In recent years video traffic has become the dominant application on the Internet with global year-on-year increases in video-oriented consumer services. Driven by improved bandwidth in both mobile and fixed networks, steadily reducing hardware costs and the development of new technologies, many existing and new classes of commercial and industrial video applications are now being upgraded or emerging. Some of the use cases for these applications include areas such as public and private security monitoring for loss prevention or intruder detection, industrial process monitoring and critical infrastructure monitoring. The use of video is becoming commonplace in defence, security, commercial, industrial, educational and health contexts. Towards optimal performances, the design or optimisation in each of these applications should be context aware and task oriented with the characteristics of the video stream (frame rate, spatial resolution, bandwidth etc.) chosen to match the use case requirements. For example, in the security domain, a task-oriented consideration may be that higher resolution video would be required to identify an intruder than to simply detect his presence. Whilst in the same case, contextual factors such as the requirement to transmit over a resource-limited wireless link, may impose constraints on the selection of optimum task-oriented parameters. This paper presents a novel, conceptually simple and easily implemented method of assessing video quality relative to its suitability for a particular task and dynamically adapting videos streams during transmission to ensure that the task can be successfully completed. Firstly we defined two principle classes of tasks: recognition tasks and event detection tasks. These task classes are further subdivided into a set of task-related profiles, each of which is associated with a set of taskoriented attributes (minimum spatial resolution, minimum frame rate etc.). For example, in the detection class

  4. Biomedical real-time monitoring in restricted and safety-critical environments

    PubMed Central

    Astaras, A; Bamidis, P D; Kourtidou-Papadeli, C; Maglaveras, N

    2008-01-01

    Biomedical signal monitoring can counteract the risk of human operator error due to inattention or fatigue in safetycritical and restrictive environments, such as in aviation, space, automobile and heavy industrial machinery operation. Real-time biomedical data acquisition is changing through advances in microelectronics fabrication, bio-MEMS and power micro-generators. Such data acquisition and processing systems are becoming increasingly miniaturised, flexible and pervasive, while data is being collected from inside the human body as well as around it. In this paper we review two related research projects exploiting this technological convergence, discuss its implications and suggest future innovation prospects through further similar cross-disciplinary synergies. PMID:19048087

  5. Electro-optic sampling analysis of timing patterns at critical internal nodes in gigabit GaAs multiplexers/demultiplexers

    NASA Astrophysics Data System (ADS)

    Zhang, X.-C.; Jain, R. K.; Hickling, R. M.

    1987-10-01

    Picosecond electro-optic sampling (EOS) has already been demonstrated by several researchers to represent a unique capability for direct noninvasive probing of GaAs integrated circuits with high temporal resolution. The use is described of the capability for a detailed analysis of on-chip waveforms at critical internal nodes in gigabit sequential logic circuits. Besides providing vital timing information between such internal nodes (and thereby providing the first clear measurements of timing parameters such as set-up and hold-times in flip-flops, and gate propagation delays is normally loaded and normally exercised gates), such as EOS measurements report the first observation of effects such as clock feedthrough at internal nodes, as well as provide indispensable information on the accuracy of the modeling/simulations that are usually done for the analysis of quirks in the internal behavior of such circuits.

  6. On the time to reach a critical number of infections in epidemic models with infective and susceptible immigrants.

    PubMed

    Almaraz, E; Gómez-Corral, A; Rodríguez-Bernal, M T

    2016-06-01

    In this paper we examine the time T to reach a critical number K0 of infections during an outbreak in an epidemic model with infective and susceptible immigrants. The underlying process X, which was first introduced by Ridler-Rowe (1967), is related to recurrent diseases and it appears to be analytically intractable. We present an approximating model inspired from the use of extreme values, and we derive formulae for the Laplace-Stieltjes transform of T and its moments, which are evaluated by using an iterative procedure. Numerical examples are presented to illustrate the effects of the contact and removal rates on the expected values of T and the threshold K0, when the initial time instant corresponds to an invasion time. We also study the exact reproduction number Rexact,0 and the population transmission number Rp, which are random versions of the basic reproduction number R0. PMID:27068519

  7. Patient-Specific Learning in Real Time for Adaptive Monitoring in Critical Care

    PubMed Central

    Szolovits, Peter

    2011-01-01

    Intensive care monitoring systems are typically developed from population data, but do not take into account the variability among individual patients’ characteristics. This study develops patient-specific alarm algorithms in real time. Classification tree and neural network learning were carried out in batch mode on individual patients’ vital sign numerics in successive intervals of incremental duration to generate binary classifiers of patient state and thus to determine when to issue an alarm. Results suggest that the performance of these classifiers follows the course of a learning curve. After eight hours of patient-specific training during each of ten monitoring sessions, our neural networks reached average sensitivity, specificity, positive predictive value, and accuracy of 0.96, 0.99, 0.79, and 0.99 respectively. The classification trees achieved 0.84, 0.98, 0.72, and 0.98 respectively. Thus, patient-specific modeling in real time is not only feasible but also effective in generating alerts at the bedside. PMID:18463000

  8. Frequency and Time Domain Analysis of Foetal Heart Rate Variability with Traditional Indexes: A Critical Survey

    PubMed Central

    Romano, Maria; Iuppariello, Luigi; Ponsiglione, Alfonso Maria; Improta, Giovanni; Bifulco, Paolo; Cesarelli, Mario

    2016-01-01

    Monitoring of foetal heart rate and its variability (FHRV) covers an important role in assessing health of foetus. Many analysis methods have been used to get quantitative measures of FHRV. FHRV has been studied in time and in frequency domain and interesting clinical results have been obtained. Nevertheless, a standardized definition of FHRV and a precise methodology to be used for its evaluation are lacking. We carried out a literature overview about both frequency domain analysis (FDA) and time domain analysis (TDA). Then, by using simulated FHR signals, we defined the methodology for FDA. Further, employing more than 400 real FHR signals, we analysed some of the most common indexes, Short Term Variability for TDA and power content of the spectrum bands and sympathovagal balance for FDA, and evaluated their ranges of values, which in many cases are a novelty. Finally, we verified the relationship between these indexes and two important parameters: week of gestation, indicator of foetal growth, and foetal state, classified as active or at rest. Our results indicate that, according to literature, it is necessary to standardize the procedure for FHRV evaluation and to consider week of gestation and foetal state before FHR analysis. PMID:27195018

  9. Frequency and Time Domain Analysis of Foetal Heart Rate Variability with Traditional Indexes: A Critical Survey.

    PubMed

    Romano, Maria; Iuppariello, Luigi; Ponsiglione, Alfonso Maria; Improta, Giovanni; Bifulco, Paolo; Cesarelli, Mario

    2016-01-01

    Monitoring of foetal heart rate and its variability (FHRV) covers an important role in assessing health of foetus. Many analysis methods have been used to get quantitative measures of FHRV. FHRV has been studied in time and in frequency domain and interesting clinical results have been obtained. Nevertheless, a standardized definition of FHRV and a precise methodology to be used for its evaluation are lacking. We carried out a literature overview about both frequency domain analysis (FDA) and time domain analysis (TDA). Then, by using simulated FHR signals, we defined the methodology for FDA. Further, employing more than 400 real FHR signals, we analysed some of the most common indexes, Short Term Variability for TDA and power content of the spectrum bands and sympathovagal balance for FDA, and evaluated their ranges of values, which in many cases are a novelty. Finally, we verified the relationship between these indexes and two important parameters: week of gestation, indicator of foetal growth, and foetal state, classified as active or at rest. Our results indicate that, according to literature, it is necessary to standardize the procedure for FHRV evaluation and to consider week of gestation and foetal state before FHR analysis. PMID:27195018

  10. A Critical Review of the Time Series of Total Solar Irradiance Satellite Observations

    NASA Astrophysics Data System (ADS)

    Willson, R. C.

    2006-12-01

    Continuous time series of total solar irradiance (TSI) observations have been constructed from the set of contiguous, redundant, overlapping total solar irradiance (TSI) measurements made by satellite experiments during the past 28 years. One, the ACRIM composite time series [Willson &Mordvinov, 2003], detects a significant upward trend in TSI of 0.04 percent per decade during solar cycles 21-23. Another, the PMOD composite [Frohlich &Lean, 1998], detects no significant trend using different combinations of TSI data sets, computational philosophy and assumptions. The potential significance of the ACRIM upward trend as a climate forcing makes it important to explore the trend difference to determine which of the two composite TSI time series best represents the measurement database. Two types of experiments have provided TSI data: self-calibrating, precision TSI monitors and Earth radiation budget (ERB) experiments. TSI monitors provide much higher accuracy and precision and are capable of self- calibrating the degradation of their sensors. The ERB experiments are designed to provide less accurate and precise TSI `boundary value' results for ERB modeling and cannot self-calibrate sensor degradation. While the optimum composite TSI time series utilizes TSI monitor results to the maximum extent possible, a two year gap in the TSI monitoring record between the ACRIM1 and ACRIM2 experiments (1989 - 1991) would have prevented compilation of a continuous record over the 28 years of satellite observations were it not for the availability of ERB results during the gap. The relationship between ACRIM1 and ACRIM2 results across the ACRIM gap can be derived using the overlapping ERB data sets: the Nimbus7/ERB and/or the ERBS/ERBE. These two choices are embodied in the construction of ACRIM and PMOD composites, respectively. The philosophy of the ACRIM composite is to use the unaltered results published by the experiment science teams and the Nimbus7/ERB ACRIM gap ratio. The

  11. Automated workflows for critical time-dependent calibrations at the CMS experiment

    NASA Astrophysics Data System (ADS)

    Cerminara, G.; van Besien, B.

    2015-12-01

    Fast and efficient methods for the calibration and the alignment of the detector are a key asset to exploit the physics potential of the Compact Muon Solenoid (CMS) detector and to ensure timely preparation of results for conferences and publications. To achieve this goal, the CMS experiment has set up a powerful framework. This includes automated workflows in the context of a prompt calibration concept, which allows for a quick turnaround of the calibration process following as fast as possible any change in running conditions. The presentation will review the design and operational experience of these workflows and the related monitoring system during the LHC Run I and focus on the development, deployment and commissioning in preparation of Run II.

  12. Critical review on Bhaishajya Kaala (time of drug administration) in Ayurveda

    PubMed Central

    Junjarwad, Ashwini V.; Savalgi, Pavan B.; Vyas, Mahesh Kumar

    2013-01-01

    Bhaishajya Kaala (time of drug administration) is an important principle to be considered while treating a disease. Still hardly a handful of physicians are seen, who account for this. To highlight its imperial role in Chikitsa, there is an immense necessity to analyze this concept, which is the need of the hour. Bhaishajya Kaala is mainly explained in relation with Bala of Roga, Rogi, particular Dosha, Dooshya, and various other factors. The comprehensive understanding of this concept involves so many questions as, why there is a difference in the number of Aushdha Kaala? What is the logic behind their indications as well as contraindications? The present paper focuses on the above points to find out the convincing answers. PMID:24049398

  13. Geoid Height Time Dependence Due to Global Glacial Isostatic Adjustment: The Critical Influence of Rotational Feedback

    NASA Astrophysics Data System (ADS)

    Peltier, W.

    2006-05-01

    It has recently been suggested in Mitrovica, Wahr et al.(2005. Geophys. J. Int. 161, 491-506) that the theory previously developed to predict the Earth's rotational response to the Late Quaternary glaciation-deglaciation cycle may require modification. This theory was initially described in Peltier (1982, Advances in Geophysics 24, 1-146) and in Wu and Peltier (1984, Geophys. J. R. astr. Soc. 76, 202-242). Its importance for understanding the GIA contribution to the modern rate of geoid height time dependence that is currently being measured by the GRACE satellite system lies in the fact that the polar wander induced by the ice-age cycle contributes to this field in an important way. It has proven possible to test the quality of the original form of the theory in a definitive way by employing Holocene inferences of relative sea level history based upon radio- carbon dated sea level index points. This test relies upon data from a wide range of sites on the Earth's surface, sites located in regions that are expcted to be most strongly influenced by the feedback of the polar wander component of the Earth's rotatonal response to the glaciation cycle onto sea level history itself. Application of the test demonstrates that the claims made in the Mitrovica, Wahr et al. paper concerning the existence of a flaw in the theory are incorrect. The previously published ICE-5G(VM2)prediction of the expected geoid height time dependence due to the GIA process is therefor secure (see Peltier, 2005. QSR 24, 1655- 1671).

  14. Statistical Analysis of fMRI Time-Series: A Critical Review of the GLM Approach.

    PubMed

    Monti, Martin M

    2011-01-01

    Functional magnetic resonance imaging (fMRI) is one of the most widely used tools to study the neural underpinnings of human cognition. Standard analysis of fMRI data relies on a general linear model (GLM) approach to separate stimulus induced signals from noise. Crucially, this approach relies on a number of assumptions about the data which, for inferences to be valid, must be met. The current paper reviews the GLM approach to analysis of fMRI time-series, focusing in particular on the degree to which such data abides by the assumptions of the GLM framework, and on the methods that have been developed to correct for any violation of those assumptions. Rather than biasing estimates of effect size, the major consequence of non-conformity to the assumptions is to introduce bias into estimates of the variance, thus affecting test statistics, power, and false positive rates. Furthermore, this bias can have pervasive effects on both individual subject and group-level statistics, potentially yielding qualitatively different results across replications, especially after the thresholding procedures commonly used for inference-making. PMID:21442013

  15. Estimation of ground water residence times in the Critical zone: insight from U activity ratios

    NASA Astrophysics Data System (ADS)

    Chabaux, Francois; Ackerer, Julien; Lucas, Yann; viville, Daniel

    2016-04-01

    The use of radioactive disequilibria as tracers and chronometers of weathering processes and related mass transfers has been recognized since the 60'. The development, over the last two decades, of analytical methods for measuring very precisely U-series nuclides (especially, 234U, 230Th and 226Ra) in environmental samples has opened up new scientific applications in Earth Surface Sciences. Here, we propose to present the potential of U activity ratios in surface waters as chronometer of water transfers at a watershed scale. This will be illustrated from studies performed at different scales, with the analysis of U activity ratios in surface waters from small watersheds (Strengbach and Ringelbach watersheds in the Vosges Mountain, France) but also from watersheds of much more regional extension (e.g., the Upper Rhine basin or the Ganges basin). These various studies show that variations of U activity ratios in surface waters are mainly associated with 234U-238U fractionations occurring during the water transfer within the bedrock, which intensity depends on two main parameters: the petro-physical characteristics of the aquifer, principally the geometry of water-rock interfaces and the duration of the water-rock interactions. This readily explains why different U activity ratios (UAR) can be observed in the different aquifers of a continental hydrosystem and hence why UAR can be used to trace the source of river waters. For a hydrological system developed on a substratum marked by fairly homogeneous petro-physical characteristics, the main parameter controlling the UAR in waters draining such a system would be the duration of the water-rock interactions. Variations of UAR in stream or spring waters of such a system can therefore be modeled using simple reactive transport model, which allows the estimation of both the dissolution rate of the bedrock and the residence time of the waters within the aquifer.

  16. Direct analysis in real time--a critical review on DART-MS.

    PubMed

    Gross, Jürgen H

    2014-01-01

    Direct analysis in real time mass spectrometry (DART-MS) has become an established technique for rapid mass spectral analysis of a large variety of samples. DART-MS is capable of analyzing the sample at atmospheric pressure, essentially in the open laboratory environment. DART-MS can be applied to compounds that have been deposited or adsorbed on to surfaces or that are being desorbed therefrom into the atmosphere. This makes DART-MS suitable and well-known for analysis of ingredients of plant materials, pesticide monitoring on vegetables, forensic and safety applications such as screening for traces of explosives, warfare agents, or illicit drugs on luggage, clothes, or bank notes, etc. DART can also be used for analysis of either solid or liquid bulk materials, as may be required in quality control, or to quickly investigate the identity of a compound from chemical synthesis. Even living organisms can be subjected to DART-MS. Driven by different needs in analytical practice, the combination of the DART ionization source and interface can be configured in multiple geometries and with various accessories to adapt the setup as required. Analysis by DART-MS relies on some sort of gas-phase ionization mechanism. In DART, initial generation of the ionizing species is by use of a corona discharge in a pure helium atmosphere which delivers excited helium atoms that, upon their release into the atmosphere, will initiate a cascade of gas-phase reactions. In the end, this results in reagent ions created from atmospheric water or (solvent) vapor in the vicinity of the surface subject to analysis where they effect a chemical ionization process. DART ionization processes may generate positive or negative ions, predominantly even-electron species, but odd-electron species do also occur. The prevailing process of analyte ion formation from a given sample is highly dependent on analyte properties. PMID:24036523

  17. Sediment residence times constrained by uranium-series isotopes: A critical appraisal of the comminution approach

    NASA Astrophysics Data System (ADS)

    Handley, Heather K.; Turner, Simon; Afonso, Juan C.; Dosseto, Anthony; Cohen, Tim

    2013-02-01

    Quantifying the rates of landscape evolution in response to climate change is inhibited by the difficulty of dating the formation of continental detrital sediments. We present uranium isotope data for Cooper Creek palaeochannel sediments from the Lake Eyre Basin in semi-arid South Australia in order to attempt to determine the formation ages and hence residence times of the sediments. To calculate the amount of recoil loss of 234U, a key input parameter used in the comminution approach, we use two suggested methods (weighted geometric and surface area measurement with an incorporated fractal correction) and typical assumed input parameter values found in the literature. The calculated recoil loss factors and comminution ages are highly dependent on the method of recoil loss factor determination used and the chosen assumptions. To appraise the ramifications of the assumptions inherent in the comminution age approach and determine individual and combined comminution age uncertainties associated to each variable, Monte Carlo simulations were conducted for a synthetic sediment sample. Using a reasonable associated uncertainty for each input factor and including variations in the source rock and measured (234U/238U) ratios, the total combined uncertainty on comminution age in our simulation (for both methods of recoil loss factor estimation) can amount to ±220-280 ka. The modelling shows that small changes in assumed input values translate into large effects on absolute comminution age. To improve the accuracy of the technique and provide meaningful absolute comminution ages, much tighter constraints are required on the assumptions for input factors such as the fraction of α-recoil lost 234Th and the initial (234U/238U) ratio of the source material. In order to be able to directly compare calculated comminution ages produced by different research groups, the standardisation of pre-treatment procedures, recoil loss factor estimation and assumed input parameter values

  18. White Oak Creek Embayment time-critical CERCLA removal action sediment-retention structure. Environmental Restoration Program

    SciTech Connect

    Not Available

    1992-09-01

    Over a 20-month period between September 1990 and April 1992, the Department of Energy (DOE), acting through Martin Marietta Energy Systems, Inc., managing contractor for the DOE Oak Ridge Field Office (DOE-OR), conducted a DOE-lead and DOE-funded time-critical removal action at the White Oak Creek Embayment (WOCE), pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The time-critical removal action specifically consisted of the design and construction of a sediment-retention structure across the mouth of WOCE to prevent off-site migration of sediments contaminated by cesium ({sup 137}Cs) into the Clinch River. Construction of a sediment-retention structure was completed in mid-April 1992. The purpose of this report is to meet the substantive requirements of 40 CFR 300.165 describing ``a complete report on the removal operation and the actions taken.`` This section of the NCP specifically addresses on-scene coordinator reports for the Environmental Protection Agency (EPA) Superfund-lead actions and includes several elements that are not applicable to this DOE-lead action. Only those sections that are pertinent and applicable are addressed in this final report.

  19. Orthodontics and esthetics of the face: from the "canons" of ancient times to contemporary pluralism. A critical review.

    PubMed

    Ioannidou-Marathiotou, Ioulia; Papamanou, Despoina A; Papadopoulos, Moschos A

    2008-01-01

    Efforts to define facial esthetics and natural attraction using objective criteria go back in time. Nowadays, the abundance of available information, the evolution in our understanding, the intermeshing of the neurosciences and biology, as well as the potential of digital technology, have provided new elements for the objective definition of esthetics and shaped new perceptions and perspectives. The aim of this paper is to attempt a critical analysis from a clinical orthodontic perspective of the conventional methods assessing facial beauty as well as of the trends and viewpoints that form today's concept of an esthetically ideal face, based on a historical review from ancient times to the 21st century. It appears that the "beauty standards" formulated artificially by the mass media and the internet remain a challenge for the orthodontist, who is called upon to explore the aspirations, motives and expectations of patients in order to be able to contribute in improving their social status and quality of life. PMID:19350056

  20. A decision-theoretic approach to the display of information for time-critical decisions: The Vista project

    NASA Technical Reports Server (NTRS)

    Horvitz, Eric; Ruokangas, Corinne; Srinivas, Sampath; Barry, Matthew

    1993-01-01

    We describe a collaborative research and development effort between the Palo Alto Laboratory of the Rockwell Science Center, Rockwell Space Operations Company, and the Propulsion Systems Section of NASA JSC to design computational tools that can manage the complexity of information displayed to human operators in high-stakes, time-critical decision contexts. We shall review an application from NASA Mission Control and describe how we integrated a probabilistic diagnostic model and a time-dependent utility model, with techniques for managing the complexity of computer displays. Then, we shall describe the behavior of VPROP, a system constructed to demonstrate promising display-management techniques. Finally, we shall describe our current research directions on the Vista 2 follow-on project.

  1. Riding the lexical speedway: a critical review on the time course of lexical selection in speech production.

    PubMed

    Strijkers, Kristof; Costa, Albert

    2011-01-01

    Speech requires time. How much time often depends on the amount of labor the brain has to perform in order to retrieve the linguistic information related to the ideas we want to express. Although most psycholinguistic research in the field of language production has focused on the net result of time required to utter words in various experimental conditions, over the last years more and more researchers pursued the objective to flesh out the time course of particular stages implicated in language production. Here we critically review these studies, with particular interest for the time course of lexical selection. First, we evaluate the data underlying the estimates of an influential temporal meta-analysis on language production (Indefrey and Levelt, 2004). We conclude that those data alone are not sufficient to provide a reliable time frame of lexical selection. Next, we discuss recent neurophysiological evidence which we argue to offer more explicit insights into the time course of lexical selection. Based on this evidence we suggest that, despite the absence of a clear time frame of how long lexical selection takes, there is sufficient direct evidence to conclude that the brain initiates lexical access within 200 ms after stimulus presentation, hereby confirming Indefrey and Levelt's estimate. In a final section, we briefly review the proposed mechanisms which could lead to this rapid onset of lexical access, namely automatic spreading activation versus specific concept selection, and discuss novel data which support the notion of spreading activation, but indicate that the speed with which this principle takes effect is driven by a top-down signal in function of the intention to engage in a speech act. PMID:22144973

  2. Variability of Residence Time tracer Concentrations at the Southern Sierra Critical Zone Observatory during the California Drought

    NASA Astrophysics Data System (ADS)

    Visser, A.; Thaw, M.; Stacy, E.; Hunsaker, C. T.; Bibby, R. K.; Deinhart, A.; Schorzman, K.; Egnatuk, C. M.; Conklin, M. H.; Esser, B.

    2015-12-01

    California water supply from high elevation snow melt is vulnerable to climate change and prolonged drought conditions. Reduced snow pack and earlier snow melt will result in a greater reliance on man-made reservoirs and subsurface catchment storage. To gain insight into the subsurface storage volume of high elevation catchments, we studied the residence time distribution of surface water leaving the Southern Sierra Critical Zone Observatory. Since October 2014, we have collected monthly samples of two residence time tracers with contrasting half-lives: sulfur-35 (87.5 days) and tritium (12.32 years). Upstream catchment area at the three nested sampling locations is 1 km2 (P301 sub-catchment), 4 km2 (Providence Creek) and ~50 km2 (Big Creek). Samples were analyzed at LLNL by low level liquid scintillation counting and noble gas mass spectrometry after helium accumulation. Variations in tracer concentrations in precipitation, both for tritium (11-24 pCi/L) and sulfur-35 (24-100 mBq/L), complicate straightforward interpretation of residence times. Sulfur-35 concentrations show that last year precipitation contributes 1% - 10% of total stream flow, even during peak snowmelt. Tritium concentrations in stream flow vary between 40% and 60% of the initial concentration in precipitation (15.5 pCi/L), indicating that water leaving the catchment has a residence time on the order of years to decades. Additional analyses of sodium-22 (2.6 year half-life) will aid in deconvoluting the residence time distribution. These low tracer concentrations can be attributed to current severe drought conditions, resulting in low discharge rates and longer residence times. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-675107

  3. Inspiratory muscle training improves cycling time-trial performance and anaerobic work capacity but not critical power.

    PubMed

    Johnson, Michael A; Sharpe, Graham R; Brown, Peter I

    2007-12-01

    We examined whether inspiratory muscle training (IMT) improved cycling time-trial performance and changed the relationship between limit work (W (lim)) and limit time (T (lim)), which is described by the parameters critical power (CP) and anaerobic work capacity (AWC). Eighteen male cyclists were assigned to either a pressure-threshold IMT or sham hypoxic-training placebo (PLC) group. Prior to and following a 6 week intervention subjects completed a 25-km cycling time-trial and three constant-power tests to establish the W (lim)-T (lim) relationship. Constant-power tests were prescribed to elicit exercise intolerance within 3-10 (Ex1), 10-20 (Ex2), and 20-30 (Ex3) min. Maximal inspiratory mouth pressure increased by (mean +/- SD) 17.1 +/- 12.2% following IMT (P < 0.01) and was accompanied by a 2.66 +/- 2.51% improvement in 25-km time-trial performance (P < 0.05); there were no changes following PLC. Constant-power cycling endurance was unchanged following PLC, as was CP (pre vs. post: 249 +/- 32 vs. 250 +/- 32 W) and AWC (30.7 +/- 12.7 vs. 30.1 +/- 12.5 kJ). Following IMT Ex1 and Ex3 cycling endurance improved by 18.3 +/- 15.1 and 15.3 +/- 19.1% (P < 0.05), respectively, CP was unchanged (264 +/- 62 vs. 263 +/- 61 W), but AWC increased from 24.8 +/- 5.6 to 29.0 +/- 8.4 kJ (P < 0.05). In conclusion, these data provide novel evidence that improvements in constant-power and cycling time-trial performance following IMT in cyclists may be explained, in part, by an increase in AWC. PMID:17874123

  4. Methionine splanchnic uptake is increased in critically ill children

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During critical illness the splanchnic area is profoundly affected. There is no information on splanchnic uptake of amino acids in vivo, in critically ill children. Methionine splanchnic uptake in critically ill children will differ from estimates in healthy adults. We studied 24 critically ill chil...

  5. Timing and extent of response in colorectal cancer: critical review of current data and implication for future trials.

    PubMed

    Aprile, Giuseppe; Fontanella, Caterina; Bonotto, Marta; Rihawi, Karim; Lutrino, Stefania Eufemia; Ferrari, Laura; Casagrande, Mariaelena; Ongaro, Elena; Berretta, Massimiliano; Avallone, Antonio; Rosati, Gerardo; Giuliani, Francesco; Fasola, Gianpiero

    2015-10-01

    The identification of new surrogate endpoints for advanced colorectal cancer is becoming crucial and, along with drug development, it represents a research field increasingly studied. Although overall survival (OS) remains the strongest trial endpoint available, it requires larger sample size and longer periods of time for an event to happen. Surrogate endpoints such as progression free survival (PFS) or response rate (RR) may overcome these issues but, as such, they need to be prospectively validated before replacing the real endpoints; moreover, they often bear many other limitations. In this narrative review we initially discuss the role of time-to-event endpoints, objective response and response rate as surrogates of OS in the advanced colorectal cancer setting, discussing also how such measures are influenced by the tumor assessment criteria currently employed. We then report recent data published about early tumor shrinkage and deepness of response, which have recently emerged as novel potential endpoint surrogates, discussing their strengths and weaknesses and providing a critical comment. Despite being very compelling, the role of such novel response measures is yet to be confirmed and their surrogacy with OS still needs to be further investigated within larger and well-designed trials. PMID:26308250

  6. Timing and extent of response in colorectal cancer: critical review of current data and implication for future trials

    PubMed Central

    Aprile, Giuseppe; Fontanella, Caterina; Bonotto, Marta; Rihawi, Karim; Lutrino, Stefania Eufemia; Ferrari, Laura; Casagrande, Mariaelena; Ongaro, Elena; Berretta, Massimiliano; Avallone, Antonio; Rosati, Gerardo; Giuliani, Francesco; Fasola, Gianpiero

    2015-01-01

    The identification of new surrogate endpoints for advanced colorectal cancer is becoming crucial and, along with drug development, it represents a research field increasingly studied. Although overall survival (OS) remains the strongest trial endpoint available, it requires larger sample size and longer periods of time for an event to happen. Surrogate endpoints such as progression free survival (PFS) or response rate (RR) may overcome these issues but, as such, they need to be prospectively validated before replacing the real endpoints; moreover, they often bear many other limitations. In this narrative review we initially discuss the role of time-to-event endpoints, objective response and response rate as surrogates of OS in the advanced colorectal cancer setting, discussing also how such measures are influenced by the tumor assessment criteria currently employed. We then report recent data published about early tumor shrinkage and deepness of response, which have recently emerged as novel potential endpoint surrogates, discussing their strengths and weaknesses and providing a critical comment. Despite being very compelling, the role of such novel response measures is yet to be confirmed and their surrogacy with OS still needs to be further investigated within larger and well-designed trials. PMID:26308250

  7. Experiencing Art with the Ill, the Elderly, and Their Caregivers

    ERIC Educational Resources Information Center

    Barrett, Terry

    2011-01-01

    This article is a personal narrative of a teaching artist reaching out to persons ill, elderly, and their caregivers because of his own experiences with cancer. As a teaching artist, the author serves schools and communities as an art critic, that is, one who facilitates discussions about works of art made by the learners or by established…

  8. Continuous Glucose Monitors and the Burden of Tight Glycemic Control in Critical Care: Can They Cure the Time Cost?

    PubMed Central

    Signal, Matthew; Pretty, Christopher G.; Chase, J. Geoffrey; Le Compte, Aaron; Shaw, Geoffrey M.

    2010-01-01

    Background Tight glycemic control (TGC) in critical care has shown distinct benefits but has also proven to be difficult to obtain. The risk of severe hypoglycemia (<40 mg/dl) raises significant concerns for safety. Added clinical burden has also been an issue. Continuous glucose monitors (CGMs) offer frequent automated measurement and thus the possibility of using them for early detection and intervention of hypoglycemic events. Additionally, regular measurement by CGM may also be able to reduce clinical burden. Aim An in silico study investigates the potential of CGM devices to reduce clinical effort in a published TGC protocol. Methods This study uses retrospective clinical data from the Specialized Relative Insulin Nutrition Titration (SPRINT) TGC study covering 20 patients from a benchmark cohort. Clinically validated metabolic system models are used to generate a blood glucose (BG) profile for each patient, resulting in 33 continuous, separate BG episodes (6881 patient hours). The in silico analysis is performed with three different stochastic noise models: two Gaussian and one first-order autoregressive. The noisy, virtual CGM BG values are filtered and used to drive the SPRINT TGC protocol. A simple threshold alarm is used to trigger glucose interventions to avert potential hypoglycemia. The Monte Carlo method was used to get robust results from the stochastic noise models. Results Using SPRINT with simulated CGM noise, the BG time in an 80–110 mg/dl band was reduced no more than 4.4% to 45.2% compared to glucometer sensors. Antihypoglycemic interventions had negligible effect on time in band but eliminated all recorded hypoglycemic episodes in these simulations. Assuming 4–6 calibration measurements per day, the nonautomated clinical measurements are reduced from an average of 16 per day to as low as 4. At 2.5 min per glucometer measurement, a daily saving of ∼25–30 min per patient could potentially be achieved. Conclusions This paper has analyzed

  9. Addressing critical environmental data gaps via low-cost, real-time, cellular-based environmental monitoring

    NASA Astrophysics Data System (ADS)

    Caylor, K. K.; Wolf, A.; Siegfried, B.

    2014-12-01

    Models in the environmental sciences are repositories in a sense of the current state of understanding of critical processes. However, as our understanding of these processes (and their accompanying models) become more granular, the data requirements to parameterize them become more limiting. In addition, as these models become more useful, they are often pressed into service for decision support, meaning that they cannot accept the data latency typical of most environmental observations. Finally, the vast majority of environmental data is generated at highly-instrumented, infrastructure-rich "mega sites" in the US/Europe, while many of the most pressing environmental issues are in rural locales and in the developing world. Cellular-based environmental sensing is a promising means to provide granular data in real time from remote locales to improve model-based forecasting using data assimilation. Applications we are working on include drought forecasting and food security; forest and crop responses to weather and climate change; and rural water usage. Over the past two years, we have developed a suite of integrated hardware, firmware, and backend APIs that accommodates an unlimited variety of sensors, and propagates these data onto the internet over mobile networks. Scientific data holds a unique role for demanding well-characterized information on sensor error and our design attempts to balance error reduction with low costs. The result is a deployment system that undercuts competing commercial products by as much as 90%, allowing more ubiquitous deployment with lower risks associated with sensor loss. Enclosure design and power management are critical ingredients for remote deployments under variable environmental conditions. Sensors push data onto cloud storage and make this data available via public API's via a backend server that accommodates additional metadata essential for interpreting observations, particularly their measurement errors. The data these pods

  10. Factors related to prolonged on-scene time during ambulance transportation for critical emergency patients in a big city in Japan: a population-based observational study

    PubMed Central

    Nagata, Isao; Abe, Toshikazu; Nakata, Yoshinori; Tamiya, Nanako

    2016-01-01

    Objectives We aimed to investigate the factors related to prolonged on-scene times, which were defined as being over 30 min, during ambulance transportation for critical emergency patients in the context of a large Japanese city. Design A population-based observational study. Setting Kawasaki City, Japan's eighth largest city. Participants The participants in this study were all critical patients (age ≥15 years) who were transported by ambulance between April 2010 and March 2013 (N=11 585). Outcome measures On-scene time during ambulance transportation for critical emergency patients. Results The median on-scene time for all patients was 17 min (IQR 13–23). There was a strong correlation between on-scene time and the number of phone calls to hospitals from emergency medical service (EMS) personnel (p<0.001). In multivariable logistic regression, the number of phone calls to hospitals from EMS personnel, intoxication, minor disease and geographical area were associated with on-scene times over 30 min. Age, gender, day of the week and time of the day were not associated with on-scene times over 30 min. Conclusions To make on-scene time shorter, it is vital to redesign our emergency system and important to develop a system that accommodates critical patients with intoxication and minor disease, and furthermore to reduce the number of phone calls to hospitals from EMS personnel. PMID:26729386

  11. Real-time determination of critical quality attributes using near-infrared spectroscopy: a contribution for Process Analytical Technology (PAT).

    PubMed

    Rosas, Juan G; Blanco, Marcel; González, Josep M; Alcalà, Manel

    2012-08-15

    Process Analytical Technology (PAT) is playing a central role in current regulations on pharmaceutical production processes. Proper understanding of all operations and variables connecting the raw materials to end products is one of the keys to ensuring quality of the products and continuous improvement in their production. Near infrared spectroscopy (NIRS) has been successfully used to develop faster and non-invasive quantitative methods for real-time predicting critical quality attributes (CQA) of pharmaceutical granulates (API content, pH, moisture, flowability, angle of repose and particle size). NIR spectra have been acquired from the bin blender after granulation process in a non-classified area without the need of sample withdrawal. The methodology used for data acquisition, calibration modelling and method application in this context is relatively inexpensive and can be easily implemented by most pharmaceutical laboratories. For this purpose, Partial Least-Squares (PLS) algorithm was used to calculate multivariate calibration models, that provided acceptable Root Mean Square Error of Predictions (RMSEP) values (RMSEP(API)=1.0 mg/g; RMSEP(pH)=0.1; RMSEP(Moisture)=0.1%; RMSEP(Flowability)=0.6 g/s; RMSEP(Angle of repose)=1.7° and RMSEP(Particle size)=2.5%) that allowed the application for routine analyses of production batches. The proposed method affords quality assessment of end products and the determination of important parameters with a view to understanding production processes used by the pharmaceutical industry. As shown here, the NIRS technique is a highly suitable tool for Process Analytical Technologies. PMID:22841062

  12. Large-Scale Analysis of Acute Ethanol Exposure in Zebrafish Development: A Critical Time Window and Resilience

    PubMed Central

    Ali, Shaukat; Champagne, Danielle L.; Alia, Alia; Richardson, Michael K.

    2011-01-01

    Background In humans, ethanol exposure during pregnancy causes a spectrum of developmental defects (fetal alcohol syndrome or FAS). Individuals vary in phenotypic expression. Zebrafish embryos develop FAS-like features after ethanol exposure. In this study, we ask whether stage-specific effects of ethanol can be identified in the zebrafish, and if so, whether they allow the pinpointing of sensitive developmental mechanisms. We have therefore conducted the first large-scale (>1500 embryos) analysis of acute, stage-specific drug effects on zebrafish development, with a large panel of readouts. Methodology/Principal Findings Zebrafish embryos were raised in 96-well plates. Range-finding indicated that 10% ethanol for 1 h was suitable for an acute exposure regime. High-resolution magic-angle spinning proton magnetic resonance spectroscopy showed that this produced a transient pulse of 0.86% concentration of ethanol in the embryo within the chorion. Survivors at 5 days postfertilisation were analysed. Phenotypes ranged from normal (resilient) to severely malformed. Ethanol exposure at early stages caused high mortality (≥88%). At later stages of exposure, mortality declined and malformations developed. Pharyngeal arch hypoplasia and behavioral impairment were most common after prim-6 and prim-16 exposure. By contrast, microphthalmia and growth retardation were stage-independent. Conclusions Our findings show that some ethanol effects are strongly stage-dependent. The phenotypes mimic key aspects of FAS including craniofacial abnormality, microphthalmia, growth retardation and behavioral impairment. We also identify a critical time window (prim-6 and prim-16) for ethanol sensitivity. Finally, our identification of a wide phenotypic spectrum is reminiscent of human FAS, and may provide a useful model for studying disease resilience. PMID:21625530

  13. The relationship between critical thinking and how time is structured in the clinical setting for students in a baccalaureate nursing program.

    PubMed

    Graham, M E

    1995-01-01

    This experimental study was undertaken to investigate the relationship between critical thinking and how time is structured in the clinical setting. A total of 93 respondents completed the Watson-Glaser Critical Thinking Appraisal (CTA) Form: 35 in the comparison group, 29 in the 2-hour/8-hour clinical groups, and 29 in the 5-hour/5-hour clinical groups. Results of the ANOVA test shows that, at Time 1, students in the comparison group had the lowest mean score (9.23) and the 2-hour/8-hour clinical groups had the highest mean score (10.94), suggesting that the three groups were not equal at Time 1 in terms of their critical thinking ability. Nevertheless, the within subjects effects shows that while all three groups indicate positive Time 1-Time 2 changes, only the 5-hour/5-hour groups show a substantial degree of improvement (10.04 to 10.75), i.e., the study groups x time interaction effect is significant (p < .001). This pattern of significance between subjects effects and differential changes in CTA scores over time, with the 5-hour/5-hour groups showing the largest degree of change is consistent among the fine sub-component of the Watson-Glaser Scale. Students in the 5-hour/5-hour groups showed the most improvement in their scores in the area of Interpretation and Evaluation of arguments which was 9.55 at Time 1 and 10.52 at Time 2. PMID:8714922

  14. A Critical Examination of American Education: A Time for Action. Conference Report (Billings, Montana, June 18-20, 1984).

    ERIC Educational Resources Information Center

    Surwill, Benedict J., Ed.

    This report presents the highlights of a conference held to critically examine the state of education in America and to set goals for the future of education in America. Those participating in the conference included public and private school teachers and administrators, college teachers and administrators, college students, parents, state…

  15. MeCP2 regulates the timing of critical period plasticity that shapes functional connectivity in primary visual cortex

    PubMed Central

    Krishnan, Keerthi; Wang, Bor-Shuen; Lu, Jiangteng; Wang, Lang; Maffei, Arianna; Cang, Jianhua; Huang, Z. Josh

    2015-01-01

    Mutations in methyl-CpG-binding protein 2 (MeCP2) cause Rett syndrome, an autism spectrum-associated disorder with a host of neurological and sensory symptoms, but the pathogenic mechanisms remain elusive. Neuronal circuits are shaped by experience during critical periods of heightened plasticity. The maturation of cortical GABA inhibitory circuitry, the parvalbumin+ (PV+) fast-spiking interneurons in particular, is a key component that regulates the initiation and termination of the critical period. Using MeCP2-null mice, we examined experience-dependent development of neural circuits in the primary visual cortex. The functional maturation of parvalbumin interneurons was accelerated upon vision onset, as indicated by elevated GABA synthetic enzymes, vesicular GABA transporter, perineuronal nets, and enhanced GABA transmission among PV interneurons. These changes correlated with a precocious onset and closure of critical period and deficient binocular visual function in mature animals. Reduction of GAD67 expression rescued the precocious opening of the critical period, suggesting its major role in MECP2-mediated regulation of experience-driven circuit development. Our results identify molecular changes in a defined cortical cell type and link aberrant developmental trajectory to functional deficits in a model of neuropsychiatric disorder. PMID:26261347

  16. Part-Time Learners in Open and Distance Learning: Revisiting the Critical Importance of Choice, Flexibility and Employability

    ERIC Educational Resources Information Center

    Butcher, John; Rose-Adams, John

    2015-01-01

    In this article, we argue that, if open learning seeks to (re)assert a social justice mission, issues of openness and flexibility are more critical than ever. Drawing on qualitative data from a National Union of Students Wales/Open University study, which explored, in the voices of Welsh students, the identity, motivation and barriers faced by…

  17. A Critical Challenge: The Engagement and Assessment of Contingent, Part-Time Adjunct Faculty Professors in United States Community Colleges

    ERIC Educational Resources Information Center

    Jolley, Michael R.; Cross, Emily; Bryant, Miles

    2014-01-01

    In 2011, according to a National Center for Education Statistics report, part-time instructional staff in all higher education institutions exceeded full-time faculty members for the first time, accounting for 50% of all instructional staff (National Center for Education Statistics [NCES], 2012). The same report indicates part-time faculty in…

  18. Investigating critical effects of variegated lubricants, glidants and hydrophilic additives on lag time of press coated ethylcellulose tablets.

    PubMed

    Patadia, Riddhish; Vora, Chintan; Mittal, Karan; Mashru, Rajashree

    2016-01-01

    The research envisaged focuses on vital impacts of variegated lubricants, glidants and hydrophilic additives on lag time of press coated ethylcellulose (EC) tablets using prednisone as a model drug. Several lubricants and glidants such as magnesium stearate, colloidal SiO2, sodium stearyl fumarate, talc, stearic acid, polyethylene glycol (6000) and glyceryl behenate were investigated to understand their effects on lag time by changing their concentrations in outer coat. Further, the effects of hydrophilic additives on lag time were examined for hydroxypropylmethylcellulose (E5), hydroxypropylcellulose (EF and SSL), povidone (K30), copovidone, polyethylene glycol (4000), lactose and mannitol. In vitro drug release testing revealed that each selected lubricant/glidant, if present even at concentration of 0.25% w/w, significantly reduced the lag time of press coated tablets. Specifically, colloidal SiO2 and/or magnesium stearate were detrimental while other lubricants/glidants were relatively less injurious. Among hydrophilic additives, freely water soluble fillers had utmost influence in lag time, whereas, comparatively less impact was observed with polymeric binders. Concisely, glidant and lubricant should be chosen to have minimal impact on lag time and further judicious selection of hydrophilic additives should be exercised for modulating lag time of pulsatile release formulations. PMID:25566928

  19. Ebola Virus Disease: Rapid Diagnosis and Timely Case Reporting are Critical to the Early Response for Outbreak Control.

    PubMed

    Stamm, Lola V

    2015-09-01

    Ebola virus disease (EVD) is a life-threatening zoonosis caused by infection with the Ebola virus. Since the first reported EVD outbreak in the Democratic Republic of the Congo, several small outbreaks have been reported in central Africa with about 2,400 cases occurring between 1976 and 2013. The 2013-2015 EVD outbreak in west Africa is the first documented outbreak in this region and the largest ever with over 27,000 cases and more than 11,000 deaths. Although EVD transmission rates have recently decreased in west Africa, this crisis continues to threaten global health and security, particularly since infected travelers could spread EVD to other resource-limited areas of the world. Because vaccines and drugs are not yet licensed for EVD, outbreak control is dependent on the use of non-pharmaceutical interventions (e.g., infection control practices, isolation of EVD cases, contact tracing with follow-up and quarantine, sanitary burial, health education). However, delays in diagnosing and reporting EVD cases in less accessible rural areas continue to hamper control efforts. New advances in rapid diagnostics for identifying presumptive EVD cases and in mobile-based technologies for communicating critical health-related information should facilitate deployment of an early response to prevent the amplification of sporadic EVD cases into large-scale outbreaks. PMID:26175026

  20. Dead-time correction for time-of-flight secondary-ion mass spectral images: a critical issue in multivariate image analysis.

    PubMed

    Tyler, Bonnie J; Peterson, Richard E

    2013-01-01

    Dead-time effects result in a non-linear detector response in the common time-of-flight secondary-ion mass spectrometry instruments. This can result in image artifacts that can often be misinterpreted. Although the Poisson correction procedure has been shown to effectively eliminate this non-linearity in spectra, applying the correction to images presents difficulties because the low number of counts per pixel can create large statistical errors. The efficacy of three approaches to dead-time correction in images has been explored. These approaches include: pixel binning, image segmentation and a binomial statistical correction. When few pixels are fully saturated, all three approaches work satisfactorily. When a large number of pixels are fully saturated, the statistical approach fails to remove the dead-time artifacts revealed by multivariate analysis. Pixel binning is accurate at higher levels of saturation so long as the bin size is much smaller than the feature size. The segmentation approach works well independent of feature size or the number of fully saturated pixels but requires an accurate segmentation algorithm. It is recommended that images be collected under conditions that minimize the number of fully saturated pixels. When this is impractical and small features are present in the image, segmentation can provide an accurate way to correct for the detector saturation effect. PMID:24707067

  1. Utilizing Social Networks in Times of Crisis: Understanding, Exploring and Analyzing Critical Incident Management at Institutions of Higher Education

    ERIC Educational Resources Information Center

    Asselin, Martha Jo

    2012-01-01

    With the rising number of major crises on college campuses today (Security on Campus Inc., 2009), institutions of higher education can benefit from understanding of how social networks may be used in times of emergency. What is currently known about the usage of social networks is not integral to the current practices of crisis management that are…

  2. Gifted and Grieving: Why It Is Critical to Offer Differential Support to Gifted Kids during Times of Loss

    ERIC Educational Resources Information Center

    Burke, Angela

    2009-01-01

    Death, illness, divorce, abuse--any degree of loss is unpleasant to discuss, unpleasant to think about. Yet, no one is exempt from the misfortunes that accompany life's journey. This includes gifted children, who at times may be perceived as self-sufficient and smart enough to figure out their own problems even if they are overwhelmingly upset…

  3. "I Just Didn't Have Enough Time..." Assisting the Busy Adult Learner Develop Critical Reading and Thinking Skills.

    ERIC Educational Resources Information Center

    Diaz-Lefebvre, Rene

    Several factors are related to adult students' completion or noncompletion of reading assignments before class--lack of study time, their motivation for taking college classes, their need to feel involved in the learning process, and their expectations for success in the classroom. One of the biggest fears of adults returning to a school…

  4. Design, Development and Evaluation of Collaborative Team Training Method in Virtual Worlds for Time-Critical Medical Procedures

    ERIC Educational Resources Information Center

    Khanal, Prabal

    2014-01-01

    Medical students acquire and enhance their clinical skills using various available techniques and resources. As the health care profession has move towards team-based practice, students and trainees need to practice team-based procedures that involve timely management of clinical tasks and adequate communication with other members of the team.…

  5. Length of time on dialysis prior to renal transplantation is a critical factor affecting patient survival after allografting.

    PubMed

    West, J C; Bisordi, J E; Squiers, E C; Latsha, R; Miller, J; Kelley, S E

    1992-01-01

    Within the past year at our transplant center we have had the experience of performing renal allografts in two patients older than 65 years, each of whom had been on hemodialysis more than 10 years. Both resulted in patient mortality within 90 days of transplant (one due to myocardial infarction, the other due to visceral ischemia with infarction). This prompted us to review retrospectively our own data (n = 204) and the national (UNOS) data (n = 10,971) regarding transplant outcome, patient age, and length of time on dialysis prior to renal transplantation. This review revealed that patient mortality after transplant increased with the length of end-stage renal disease (dialysis, regardless of type) independent of age, the greatest mortality occurring within the first 6 months of transplant (and not thereafter); graft survival was similar for all age cohorts analyzed. Our review of the literature reveals a paucity of articles pertaining to post-transplant mortality and length of time on dialysis prior to transplant. Our results indicate the following possible conclusions. (1) The length of time of end-stage renal disease therapy prior to renal transplantation is a significant and independent risk factor for post-transplant mortality. (2) Higher priority should be given to this factor when formulating strategies for allocation of scarce resources. (3) Patients on dialysis for extended periods of time who are elderly may be at particularly high risk. (4) Patients being considered for renal transplant should be informed of their individual risk factors for mortality post-transplant based on length of ESRD therapy. (5) Renal transplantation should be considered as early as possible in patients with ESRD (or imminent ESRD). PMID:14621760

  6. Flux-lines lattice order and critical current studied by time-of-flight small-angle neutron scattering

    NASA Astrophysics Data System (ADS)

    Pautrat, Alain; Brulet, Annie; Simon, Charles; Mathieu, Patrice

    2012-05-01

    Small-angle neutron scattering is a historical technique to study the flux-lines lattice (FLL) in a superconductor. Structural characteristics of the FLL can be revealed, providing fundamental information for the physics of a vortex lattice. However, the spatial resolution is limited and all of the correlation lengths of order are difficult to extract with precision. We show here that a time-of-flight technique reveals the Bragg peak of the FLL, and also its translational order with a better resolution. We discuss the implication of these results for pinning mechanisms in a niobium sample.

  7. Critical elements in implementations of just-in-time management: empirical study of cement industry in Pakistan.

    PubMed

    Qureshi, Muhammad Imran; Iftikhar, Mehwish; Bhatti, Mansoor Nazir; Shams, Tauqeer; Zaman, Khalid

    2013-01-01

    In recent years, inventory management is continuous challenge for all organizations not only due to heavy cost associated with inventory holding, but also it has a great deal to do with the organizations production process. Cement industry is a growing sector of Pakistan's economy which is now facing problems in capacity utilization of their plants. This study attempts to identify the key strategies for successful implementation of just-in-time (JIT) management philosophy on the cement industry of Pakistan. The study uses survey responses from four hundred operations' managers of cement industry in order to know about the advantages and benefits that cement industry have experienced by Just in time (JIT) adoption. The results show that implementing the quality, product design, inventory management, supply chain and production plans embodied through the JIT philosophy which infect enhances cement industry competitiveness in Pakistan. JIT implementation increases performance by lower level of inventory, reduced operations & inventory costs was reduced eliminates wastage from the processes and reduced unnecessary production which is a big challenge for the manufacturer who are trying to maintain the continuous flow processes. JIT implementation is a vital manufacturing strategy that reaches capacity utilization and minimizes the rate of defect in continuous flow processes. The study emphasize the need for top management commitment in order to incorporate the necessary changes that need to take place in cement industry so that JIT implementation can take place in an effective manner. PMID:24340248

  8. Inhibition of mitochondrial fission as a molecular target for cardioprotection: critical importance of the timing of treatment.

    PubMed

    Dong, Yi; Undyala, Vishnu V R; Przyklenk, Karin

    2016-09-01

    Recent attention has focused on the concept that mitochondrial dynamics-that is, the balance between mitochondrial fusion and fission (fragmentation)-may play a pivotal role in determining cell fate in the setting of myocardial ischemia-reperfusion injury. In this regard, there is an emerging consensus that: (1) ischemia-reperfusion favors mitochondrial fragmentation and (2) strategies aimed at inhibiting the translocation of dynamin-related protein 1 (DRP1: the 'master regulator' of fission) from the cytosol to the mitochondria, when initiated as a pretreatment, are cardioprotective. However, direct molecular evidence of a cause-and-effect relationship between mitochondrial fission and cardiomyocyte death has not been established. To address this issue, we used a well-characterized in vitro, immortal cultured cardiomyocyte model to establish whether subcellular redistribution of DRP1 to mitochondria: (1) is triggered by hypoxia-reoxygenation; (2) plays a causal role in hypoxia-reoxygenation-induced cytochrome c release (harbinger of apoptosis) and cardiomyocyte death; and (3) represents a molecular mechanism that can be targeted in a clinically relevant time frame to render cells resistant to lethal hypoxia-reoxygenation injury. Our results provide direct evidence that the redistribution of DRP1 to mitochondria contributes to cardiomyocyte death, and corroborate the previous observations that the pre-ischemic inhibition of DRP1 translocation is cardioprotective. Moreover, we report the novel finding that-in marked contrast to the data obtained with pretreatment-inhibition of DRP1 translocation initiated at the time of reoxygenation had complex, unexpected and unfavorable consequences: i.e., attenuated cardiomyocyte apoptosis but exacerbated total cell death, possibly via concurrent upregulation of necroptosis. PMID:27573530

  9. Decision solution, data manipulation and trust: The (un-)willingness to donate organs in Germany in critical times.

    PubMed

    Schwettmann, Lars

    2015-07-01

    In 2011 and 2012 a change of rules and a data-manipulation scandal focused German public attention on organ donation. This increased citizens' background knowledge as well as their willingness to respond to surveys. The present study is an effort to seize this research opportunity and to create evidence on which policy recommendations can be conceivably based. It uses data from two major representative surveys from 2011 to 2012 to address four central questions: Which characteristics, experiences and attitudes correlate with the written or unwritten willingness of individuals to donate (WTD) their own organs post-mortem? How has the WTD changed over time? To what extent does the WTD depend on normative trust? Which factors correlate with trust? The data is analyzed through summary statistics and regression models. Several hypotheses regarding factors connected with the WTD are confirmed in the survey results. Altruistic motives, relevant knowledge and trust are decisive. The special role of trust is corroborated by the data. As current German politics prevents the introduction of post-mortem donation incentives, potential policy making proposals are restricted to institutional changes to regain trust including the implementation of an organ donor registry and the advancement of counselling talks with general practitioners. PMID:25684705

  10. Time to Give Up on Cardioprotection? A Critical Appraisal of Clinical Studies on Ischemic Pre-, Post-, and Remote Conditioning.

    PubMed

    Heusch, Gerd; Rassaf, Tienush

    2016-08-19

    The mortality from acute myocardial infarction (AMI) remains significant, and the prevalence of post-myocardial infarction heart failure is increasing. Therefore, cardioprotection beyond timely reperfusion is needed. Conditioning procedures are the most powerful cardioprotective interventions in animal experiments. However, ischemic preconditioning cannot be used to reduce infarct size in patients with AMI because its occurrence is not predictable; several studies in patients undergoing surgical coronary revascularization report reduced release of creatine kinase and troponin. Ischemic postconditioning reduces infarct size in most, but not all, studies in patients undergoing interventional reperfusion of AMI, but may require direct stenting and exclusion of patients with >6 hours of symptom onset to protect. Remote ischemic conditioning reduces infarct size in patients undergoing interventional reperfusion of AMI, elective percutaneous or surgical coronary revascularization, and other cardiovascular surgery in many, but not in all, studies. Adequate dose-finding phase II studies do not exist. There are only 2 phase III trials, both on remote ischemic conditioning in patients undergoing cardiovascular surgery, both with neutral results in terms of infarct size and clinical outcome, but also both with major problems in trial design. We discuss the difficulties in translation of cardioprotection from animal experiments and proof-of-concept trials to clinical practice. Given that most studies on ischemic postconditioning and all studies on remote ischemic preconditioning in patients with AMI reported reduced infarct size, it would be premature to give up on cardioprotection. PMID:27539973

  11. A complexity basis for phenomenology: How information states at criticality offer a new approach to understanding experience of self, being and time.

    PubMed

    Hankey, Alex

    2015-12-01

    In the late 19th century Husserl studied our internal sense of time passing, maintaining that its deep connections into experience represent prima facie evidence for it as the basis for all investigations in the sciences: Phenomenology was born. Merleau-Ponty focused on perception pointing out that any theory of experience must accord with established aspects of biology i.e. be embodied. Recent analyses suggest that theories of experience require non-reductive, integrative information, together with a specific property connecting them to experience. Here we elucidate a new class of information states with just such properties found at the loci of control of complex biological systems, including nervous systems. Complexity biology concerns states satisfying self-organized criticality. Such states are located at critical instabilities, commonly observed in biological systems, and thought to maximize information diversity and processing, and hence to optimize regulation. Major results for biology follow: why organisms have unusually low entropies; and why they are not merely mechanical. Criticality states form singular self-observing systems, which reduce wave packets by processes of perfect self-observation associated with feedback gain g = 1. Analysis of their information properties leads to identification of a new kind of information state with high levels of internal coherence, and feedback loops integrated into their structure. The major idea presented here is that the integrated feedback loops are responsible for our 'sense of self', and also the feeling of continuity in our sense of time passing. Long-range internal correlations guarantee a unique kind of non-reductive, integrative information structure enabling such states to naturally support phenomenal experience. Being founded in complexity biology, they are 'embodied'; they also fulfill the statement that 'The self is a process', a singular process. High internal correlations and René Thom

  12. Molecular and morphological phylogenetics of chelonine parasitoid wasps (Hymenoptera: Braconidae), with a critical assessment of divergence time estimations.

    PubMed

    Kittel, Rebecca N; Austin, Andrew D; Klopfstein, Seraina

    2016-08-01

    Parasitoid wasps of the subfamily Cheloninae are both species rich and poorly known. Although the taxonomy of Cheloninae appears to be relatively stable, there is no clear understanding of relationships among higher-level taxa. We here applied molecular phylogenetic analyses using three markers (COI, EF1α, 28S) and 37 morphological characters to elucidate the evolution and systematics of these wasps. Analyses were based on 83 specimens representing 13 genera. All genera except Ascogaster, Phanerotoma, and Pseudophanerotoma formed monophyletic groups; Furcidentia (stat. rev.) is raised to generic rank. Neither Chelonus (Chelonus) nor Chelonus (Microchelonus) were recovered as monophyletic, but together formed a monophyletic lineage. The tribes Chelonini and Odontosphaeropygini formed monophyletic groups, but the Phanerotomini sensu Zettel and Pseudophanerotomini were retrieved as either para- or polyphyletic. The genera comprising the former subfamily Adeliinae were confirmed as being nested within the Cheloninae. To estimate the age of the subfamily, we used 16 fossil taxa. Three approaches were compared: fixed-rate dating, node dating, and total-evidence dating, with age estimates differing greatly between the three methods. Shortcomings of each approach in relation to our dataset are discussed, and none of the age estimates is deemed sufficiently reliable. Given that most dating studies use a single method only, in most cases without presenting analyses on the sensitivity to priors, it is likely that numerous age estimates in the literature suffer from a similar lack of robustness. We argue for a more rigorous approach to dating analyses and for a faithful presentation of uncertainties in divergence time estimates. Given the results of the phylogenetic analysis the following taxonomic changes are proposed: Furcidentia Zettel (stat. rev.), previously treated as a subgenus of Pseudophanerotoma Zettel is raised to generic rank; Microchelonus Szépligeti (syn. nov

  13. Development of Electronic Nose and Near Infrared Spectroscopy Analysis Techniques to Monitor the Critical Time in SSF Process of Feed Protein

    PubMed Central

    Jiang, Hui; Chen, Quansheng

    2014-01-01

    In order to assure the consistency of the final product quality, a fast and effective process monitoring is a growing need in solid state fermentation (SSF) industry. This work investigated the potential of non-invasive techniques combined with the chemometrics method, to monitor time-related changes that occur during SSF process of feed protein. Four fermentation trials conducted were monitored by an electronic nose device and a near infrared spectroscopy (NIRS) spectrometer. Firstly, principal component analysis (PCA) and independent component analysis (ICA) were respectively applied to the feature extraction and information fusion. Then, the BP_AdaBoost algorithm was used to develop the fused model for monitoring of the critical time in SSF process of feed protein. Experimental results showed that the identified results of the fusion model are much better than those of the single technique model both in the training and validation sets, and the complexity of the fusion model was also less than that of the single technique model. The overall results demonstrate that it has a high potential in online monitoring of the critical moment in SSF process by use of integrating electronic nose and NIRS techniques, and data fusion from multi-technique could significantly improve the monitoring performance of SSF process. PMID:25330048

  14. Phase transitions and critical phenomena in the two-dimensional Ising model with dipole interactions: A short-time dynamics study

    NASA Astrophysics Data System (ADS)

    Horowitz, C. M.; Bab, M. A.; Mazzini, M.; Puzzo, M. L. Rubio; Saracco, G. P.

    2015-10-01

    The ferromagnetic Ising model with antiferromagnetic dipole interactions is investigated by means of Monte Carlo simulations, focusing on the characterization of the phase transitions between the tetragonal liquid and stripe of width h phases. The dynamic evolution of the physical observables is analyzed within the short-time regime for 0.5 ≤δ ≤1.3 , where δ is the ratio between the short-range exchange and the long-range dipole interaction constants. The obtained results for the interval 0.5 ≤δ ≤1.2 indicate that the phase transition line between the h =1 stripe and tetragonal liquid phases is continuous. This finding contributes to clarifying the controversy about the order of this transition. This controversy arises from the difficulties introduced in the simulations due to the presence of long-range dipole interactions, such as an important increase in the simulation times that limits the system size used, strong finite size effects, as well as to the existence of multiple metastable states at low temperatures. The study of the short-time dynamics of the model allows us to avoid these hindrances. Moreover, due to the fact that the finite-size effects do not significantly affect the power-law behavior exhibited in the observables within the short-time regime, the results could be attributed to those corresponding to the thermodynamic limit. As a consequence of this, a careful characterization of the critical behavior for the whole transition line is performed by giving the complete set of critical exponents.

  15. Critical evaluation of a simple retention time predictor based on LogKow as a complementary tool in the identification of emerging contaminants in water.

    PubMed

    Bade, Richard; Bijlsma, Lubertus; Sancho, Juan V; Hernández, Felix

    2015-07-01

    There has been great interest in environmental analytical chemistry in developing screening methods based on liquid chromatography-high resolution mass spectrometry (LC-HRMS) for emerging contaminants. Using HRMS, compound identification relies on the high mass resolving power and mass accuracy attainable by these analyzers. When dealing with wide-scope screening, retention time prediction can be a complementary tool for the identification of compounds, and can also reduce tedious data processing when several peaks appear in the extracted ion chromatograms. There are many in silico, Quantitative Structure-Retention Relationship methods available for the prediction of retention time for LC. However, most of these methods use commercial software to predict retention time based on various molecular descriptors. This paper explores the applicability and makes a critical discussion on a far simpler and cheaper approach to predict retention times by using LogKow. The predictor was based on a database of 595 compounds, their respective LogKow values and a chromatographic run time of 18min. Approximately 95% of the compounds were found within 4.0min of their actual retention times, and 70% within 2.0min. A predictor based purely on pesticides was also made, enabling 80% of these compounds to be found within 2.0min of their actual retention times. To demonstrate the utility of the predictors, they were successfully used as an additional tool in the identification of 30 commonly found emerging contaminants in water. Furthermore, a comparison was made by using different mass extraction windows to minimize the number of false positives obtained. PMID:25882420

  16. Sexual maturation in underfed weight-matched rats. A test of the "critical body weight" theory of pubertal timing in males.

    PubMed

    Glass, A R; Anderson, J; Herbert, D

    1987-01-01

    A popular current theory proposes that the timing of puberty is related to attainment of a critical level of body weight or body fatness. These critical body weight and critical body fat theories have been studied almost exclusively in females. To explore these theories in males, we tested a corollary of these hypotheses: are male rats of the same weight all at the same level of sexual maturation irrespective of prior growth rate? Male rats growing in body weight at five different rates due to various degrees of underfeeding (beginning at weaning) were sacrificed at body weight milestones of 123 and 279 grams. At the first weight milestone, significant (P less than 0.01) inverse correlations were observed among these weight-matched rats between the preceding rate of body weight growth and prostate weight, seminal vesicle weight, testis weight, serum testosterone, and daily sperm production rate, indicating that the underfed animals were more sexually mature. Testis histology also showed that spermatogenic development increased progressively as the prior rate of body weight growth was reduced. These parameters of sexual maturation tended to correlate inversely with body fatness (i.e., leaner animals were more sexually mature) and directly with body length (i.e., longer animals were more sexually mature). By the second body weight milestone, however, the degree of prior underfeeding exerted little effect on those indices of sexual development. We conclude that the degree of sexual maturation in weight-matched animals with varying previous patterns of body weight growth correlates inversely with body fatness and the rate of body weight growth but correlates directly with body length.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3583906

  17. Testing the Critical Window Hypothesis of Timing and Duration of Estradiol Treatment on Hypothalamic Gene Networks in Reproductively Mature and Aging Female Rats

    PubMed Central

    Yin, Weiling; Maguire, Sean M.; Pham, Brian; Garcia, Alexandra N.; Dang, Nguyen-Vy; Liang, Jingya; Wolfe, Andrew; Hofmann, Hans A.

    2015-01-01

    At menopause, the dramatic loss of ovarian estradiol (E2) necessitates the adaptation of estrogen-sensitive neurons in the hypothalamus to an estrogen-depleted environment. We developed a rat model to test the “critical window” hypothesis of the effects of timing and duration of E2 treatment after deprivation on the hypothalamic neuronal gene network in the arcuate nucleus and the medial preoptic area. Rats at 2 ages (reproductively mature or aging) were ovariectomized and given E2 or vehicle replacement regimes of differing timing and duration. Using a 48-gene quantitative low-density PCR array and weighted gene coexpression network analysis, we identified gene modules differentially regulated by age, timing, and duration of E2 treatment. Of particular interest, E2 status differentially affected suites of genes in the hypothalamus involved in energy balance, circadian rhythms, and reproduction. In fact, E2 status was the dominant factor in determining gene modules and hormone levels; age, timing, and duration had more subtle effects. Our results highlight the plasticity of hypothalamic neuroendocrine systems during reproductive aging and its surprising ability to adapt to diverse E2 replacement regimes. PMID:26018250

  18. Time-critical social mobilization.

    PubMed

    Pickard, Galen; Pan, Wei; Rahwan, Iyad; Cebrian, Manuel; Crane, Riley; Madan, Anmol; Pentland, Alex

    2011-10-28

    The World Wide Web is commonly seen as a platform that can harness the collective abilities of large numbers of people to accomplish tasks with unprecedented speed, accuracy, and scale. To explore the Web's ability for social mobilization, the Defense Advanced Research Projects Agency (DARPA) held the DARPA Network Challenge, in which competing teams were asked to locate 10 red weather balloons placed at locations around the continental United States. Using a recursive incentive mechanism that both spread information about the task and incentivized individuals to act, our team was able to find all 10 balloons in less than 9 hours, thus winning the Challenge. We analyzed the theoretical and practical properties of this mechanism and compared it with other approaches. PMID:22034432

  19. Dynamics of pulsed laser ablation plasmas in high-density CO2 near the critical point investigated by time-resolved shadowgraph imaging

    NASA Astrophysics Data System (ADS)

    Urabe, Keiichiro; Kato, Toru; Himeno, Shohei; Kato, Satoshi; Stauss, Sven; Baba, Motoyoshi; Suemoto, Tohru; Terashima, Kazuo

    2013-09-01

    Pulsed laser ablation (PLA) plasmas generated in high-density gases and liquids are promising for the synthesis of nanomaterials. However, the characteristics of such plasmas are still not well understood. In order to improve the understandings of PLA plasmas in high-density fluids including gases, liquids, and supercritical fluids (SCFs), we have investigated the dynamics of PLA plasmas in high-density carbon dioxide (CO2) . We report on experimental results of time-resolved shadowgraph imaging, from the generation of plasma plume to the extinction of cavitation bubbles. Shadowgraph images revealed that the PLA plasma dynamics showed two distinct behaviors. These are divided by gas-liquid coexistence curve and the so-called Widom line, which separates gas-like and liquid-like SCF domains. Furthermore, cavitation bubble observed in liquid CO2 near the critical point showed peculiar characteristics, the formation of an inner bubble and an outer shell structure, which so far has never been reported. The experiments indicate that thermophysical properties of PLA plasmas can be tuned by controlling solvent temperature and pressure around the critical point, which may be useful for materials processing. This work was supported financially in part by a Grant-in-Aid for Scientific Research on Innovative Areas (No. 21110002) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan.

  20. Critical Thinking.

    ERIC Educational Resources Information Center

    Callison, Daniel

    1998-01-01

    Distinguishes between critical and creative thinking and discusses critical-thinking in relation to modern instructional programs and information literacy. Outlines goals in critical-thinking curriculum, critical thinking skills (student disposition, interpretation, analysis, evaluation, inference, presenting argument, and reflection), and…

  1. Time?

    NASA Astrophysics Data System (ADS)

    Amoroso, Richard L.

    2013-09-01

    The concept of time in the `clockwork' Newtonian world was irrelevant; and has generally been ignored until recently by several generations of physicists since the implementation of quantum mechanics. We will set aside the utility of time as a property relating to physical calculations of events relating to a metrics line element or as an aspect of the transformation of a particles motion/interaction in a coordinate system or in relation to thermodynamics etc., i.e. we will discard all the usual uses of time as a concept used to circularly define physical parameters in terms of other physical parameters; concentrating instead on time as an aspect of the fundamental cosmic topology of our virtual reality especially as it inseparably relates to the nature and role of the observer in natural science.

  2. Hillslope lowering rates and mobile-regolith residence times from in situ and meteoric 10Be analysis: Boulder Creek Critical Zone Observatory, Colorado

    NASA Astrophysics Data System (ADS)

    Foster, M. A.; Anderson, R. S.; Wyshnytzky, C.; Ouimet, W. B.; Dethier, D. P.

    2014-12-01

    Mobile regolith is produced as weathered saprolite is entrained into the mobile layer. The rate of mobile-regolith production and its residence time on hillslopes shapes the topography and evolution of hillslopes. We calculate the production rate of mobile regolith and the mobile-regolith residence times on active hillslopes in Gordon Gulch, within the Boulder Creek Critical Zone Observatory (CZO), Colorado. We find mobile-regolith production rates (average 3.1 cm/ka) and residence times (average 10-20 ka) derived from both in situand meteoric methods agree. Lowering-rates derived from our study are also comparable to basin-averaged denudation rates for small basins in the Colorado Front Range (Dethier and Lazarus, 2006). In this study, we have measured both in situ and meteoric 10Be in saprolite and mobile regolith separately. We find that, on average, two-thirds of in situ 10Be is produced within saprolite, and that at least one-tenth of the meteoric 10Be inventories are stored in saprolite. In the case of in situ 10Be, this simply reflects the exponential fall-off in production rates through a thin mobile-regolith cover. In the case of meteoric 10Be, our calculations suggest that >40% of the meteoric 10Be deposition occurs within the saprolite. Most studies that utilize 10Be report residence times and soil-production rates based on concentrations in either the mobile regolith or saprolite; therefore, our 10Be data highlight the importance of clearly identifying mobile and immobile portions of the regolith, constraining its 10Be inventory, and use of consistent terminology for the mobile-layer.

  3. Thinking Critically about Critical Thinking

    ERIC Educational Resources Information Center

    Mulnix, Jennifer Wilson

    2012-01-01

    As a philosophy professor, one of my central goals is to teach students to think critically. However, one difficulty with determining whether critical thinking can be taught, or even measured, is that there is widespread disagreement over what critical thinking actually is. Here, I reflect on several conceptions of critical thinking, subjecting…

  4. Assessment of critical exposure and outcome windows in time-to-event analysis with application to air pollution and preterm birth study.

    PubMed

    Chang, Howard H; Warren, Joshua L; Darrow, Lnydsey A; Reich, Brian J; Waller, Lance A

    2015-07-01

    In reproductive epidemiology, there is a growing interest to examine associations between air pollution exposure during pregnancy and the risk of preterm birth (PTB). One important research objective is to identify critical periods of exposure and estimate the associated effects at different stages of pregnancy. However, population studies have reported inconsistent findings. This may be due to limitations from the standard analytic approach of treating PTB as a binary outcome without considering time-varying exposures together over the course of pregnancy. To address this research gap, we present a Bayesian hierarchical model for conducting a comprehensive examination of gestational air pollution exposure by estimating the joint effects of weekly exposures during different vulnerable periods. Our model also treats PTB as a time-to-event outcome to address the challenge of different exposure lengths among ongoing pregnancies. The proposed model is applied to a dataset of geocoded birth records in the Atlanta metropolitan area between 1999-2005 to examine the risk of PTB associated with gestational exposure to ambient fine particulate matter [Formula: see text]m in aerodynamic diameter (PM[Formula: see text]). We find positive associations between PM[Formula: see text] exposure during early and mid-pregnancy, and evidence that associations are stronger for PTBs occurring around week 30. PMID:25572998

  5. The critical time of avian leukosis virus subgroup J-mediated immunosuppression during early stage infection in specific pathogen-free chickens.

    PubMed

    Wang, Feng; Wang, Xiaowei; Chen, Hongbo; Liu, Jianzhu; Cheng, Ziqiang

    2011-09-01

    The critical time of avian leukosis virus subgroup J (ALV-J)-mediated immunosuppression was determined by body weight, relative immune organ weight, histopathology, and presence of group specific antigen and antibodies in specific pathogen-free (SPF) chickens. CD4(+) and CD8(+) cell activity in the spleen, total and differential leukocyte counts in blood, and viral RNA levels in spleen were measured. Significant growth suppression was observed in the two ALV-J-infected groups. A strong immune response by infected groups was present in spleen at 2-weeks-of-age, but after 4-weeks-of-age, the response decreased quickly. The thymus and bursa showed persistent immunosuppression until 4-weeks-of-age. Proliferation of fibroblasts and dendritic cells were observed in immune organs at 4- and 5-weeks-of-age. However, the granulocyte cell number was markedly lower in the infected groups than in the control group. In group 1 (day 1 infection) CD4(+) cells increased during the second week but significantly decreased during the fourth week, while group 2 (day 7 infection) showed the opposite effect. Viral RNA increased significantly by the fourth week. These data identify 3~4 weeks post-infection as the key time at which the ALV-J virus exerts its immunosuppressive effects on the host. PMID:21897096

  6. The critical time of avian leukosis virus subgroup J-mediated immunosuppression during early stage infection in specific pathogen-free chickens

    PubMed Central

    Wang, Feng; Wang, Xiaowei; Chen, Hongbo; Liu, Jianzhu

    2011-01-01

    The critical time of avian leukosis virus subgroup J (ALV-J)-mediated immunosuppression was determined by body weight, relative immune organ weight, histopathology, and presence of group specific antigen and antibodies in specific pathogen-free (SPF) chickens. CD4+ and CD8+ cell activity in the spleen, total and differential leukocyte counts in blood, and viral RNA levels in spleen were measured. Significant growth suppression was observed in the two ALV-J-infected groups. A strong immune response by infected groups was present in spleen at 2-weeks-of-age, but after 4-weeks-of-age, the response decreased quickly. The thymus and bursa showed persistent immunosuppression until 4-weeks-of-age. Proliferation of fibroblasts and dendritic cells were observed in immune organs at 4- and 5-weeks-of-age. However, the granulocyte cell number was markedly lower in the infected groups than in the control group. In group 1 (day 1 infection) CD4+ cells increased during the second week but significantly decreased during the fourth week, while group 2 (day 7 infection) showed the opposite effect. Viral RNA increased significantly by the fourth week. These data identify 3~4 weeks post-infection as the key time at which the ALV-J virus exerts its immunosuppressive effects on the host. PMID:21897096

  7. Critical Care

    MedlinePlus

    Critical care helps people with life-threatening injuries and illnesses. It might treat problems such as complications from surgery, ... attention by a team of specially-trained health care providers. Critical care usually takes place in an ...

  8. Critical Thoughts on Critical Thinking

    ERIC Educational Resources Information Center

    Cody, Dean E.

    2006-01-01

    Scholars in many academic areas, including librarians, devote a significant amount of thought to critical thinking. Surveying views of its use and possibility, the author considers some key librarians' thoughts on critical thinking. In conclusion, the inability to define critical thinking means that librarians need to emphasize control of…

  9. Critical Thinking vs. Critical Consciousness

    ERIC Educational Resources Information Center

    Doughty, Howard A.

    2006-01-01

    This article explores four kinds of critical thinking. The first is found in Socratic dialogues, which employ critical thinking mainly to reveal logical fallacies in common opinions, thus cleansing superior minds of error and leaving philosophers free to contemplate universal verities. The second is critical interpretation (hermeneutics) which…

  10. Critically Thinking about Critical Thinking

    ERIC Educational Resources Information Center

    Weissberg, Robert

    2013-01-01

    In this article, the author states that "critical thinking" has mesmerized academics across the political spectrum and that even high school students are now being called upon to "think critically." He furthers adds that it is no exaggeration to say that "critical thinking" has quickly evolved into a scholarly…

  11. How Critical Is Critical Thinking?

    ERIC Educational Resources Information Center

    Shaw, Ryan D.

    2014-01-01

    Recent educational discourse is full of references to the value of critical thinking as a 21st-century skill. In music education, critical thinking has been discussed in relation to problem solving and music listening, and some researchers suggest that training in critical thinking can improve students' responses to music. But what exactly is…

  12. Critical Care

    MedlinePlus

    Critical care helps people with life-threatening injuries and illnesses. It might treat problems such as complications from surgery, accidents, infections, and severe breathing problems. It involves ...

  13. Criticality Model

    SciTech Connect

    A. Alsaed

    2004-09-14

    The ''Disposal Criticality Analysis Methodology Topical Report'' (YMP 2003) presents the methodology for evaluating potential criticality situations in the monitored geologic repository. As stated in the referenced Topical Report, the detailed methodology for performing the disposal criticality analyses will be documented in model reports. Many of the models developed in support of the Topical Report differ from the definition of models as given in the Office of Civilian Radioactive Waste Management procedure AP-SIII.10Q, ''Models'', in that they are procedural, rather than mathematical. These model reports document the detailed methodology necessary to implement the approach presented in the Disposal Criticality Analysis Methodology Topical Report and provide calculations utilizing the methodology. Thus, the governing procedure for this type of report is AP-3.12Q, ''Design Calculations and Analyses''. The ''Criticality Model'' is of this latter type, providing a process evaluating the criticality potential of in-package and external configurations. The purpose of this analysis is to layout the process for calculating the criticality potential for various in-package and external configurations and to calculate lower-bound tolerance limit (LBTL) values and determine range of applicability (ROA) parameters. The LBTL calculations and the ROA determinations are performed using selected benchmark experiments that are applicable to various waste forms and various in-package and external configurations. The waste forms considered in this calculation are pressurized water reactor (PWR), boiling water reactor (BWR), Fast Flux Test Facility (FFTF), Training Research Isotope General Atomic (TRIGA), Enrico Fermi, Shippingport pressurized water reactor, Shippingport light water breeder reactor (LWBR), N-Reactor, Melt and Dilute, and Fort Saint Vrain Reactor spent nuclear fuel (SNF). The scope of this analysis is to document the criticality computational method. The criticality

  14. Empathy and the Critic

    ERIC Educational Resources Information Center

    Jurecic, Ann

    2011-01-01

    "Empathy" is a much-discussed term in the humanities these days. While some critics value it and argue that literature desirably promotes it, other critics worry that appeals to this emotion will neglect important matters of social context. In the literature classroom, the best approach is to take time to consider how texts complicate the impulse…

  15. Critical Chain Exercises

    ERIC Educational Resources Information Center

    Doyle, John Kevin

    2010-01-01

    Critical Chains project management focuses on holding buffers at the project level vs. task level, and managing buffers as a project resource. A number of studies have shown that Critical Chain project management can significantly improve organizational schedule fidelity (i.e., improve the proportion of projects delivered on time) and reduce…

  16. Critical Muralism

    ERIC Educational Resources Information Center

    Rosette, Arturo

    2009-01-01

    This study focuses on the development and practices of Critical Muralists--community-educator-artist-leader-activists--and situates these specifically in relation to the Mexican mural tradition of los Tres Grandes and in relation to the history of public art more generally. The study examines how Critical Muralists address artistic and…

  17. CISN Display - Reliable Delivery of Real-time Earthquake Information, Including Rapid Notification and ShakeMap to Critical End Users

    NASA Astrophysics Data System (ADS)

    Rico, H.; Hauksson, E.; Thomas, E.; Friberg, P.; Given, D.

    2002-12-01

    The California Integrated Seismic Network (CISN) Display is part of a Web-enabled earthquake notification system alerting users in near real-time of seismicity, and also valuable geophysical information following a large earthquake. It will replace the Caltech/USGS Broadcast of Earthquakes (CUBE) and Rapid Earthquake Data Integration (REDI) Display as the principal means of delivering graphical earthquake information to users at emergency operations centers, and other organizations. Features distinguishing the CISN Display from other GUI tools are a state-full client/server relationship, a scalable message format supporting automated hyperlink creation, and a configurable platform-independent client with a GIS mapping tool; supporting the decision-making activities of critical users. The CISN Display is the front-end of a client/server architecture known as the QuakeWatch system. It is comprised of the CISN Display (and other potential clients), message queues, server, server "feeder" modules, and messaging middleware, schema and generators. It is written in Java, making it platform-independent, and offering the latest in Internet technologies. QuakeWatch's object-oriented design allows components to be easily upgraded through a well-defined set of application programming interfaces (APIs). Central to the CISN Display's role as a gateway to other earthquake products is its comprehensive XML-schema. The message model starts with the CUBE message format, but extends it by provisioning additional attributes for currently available products, and those yet to be considered. The supporting metadata in the XML-message provides the data necessary for the client to create a hyperlink and associate it with a unique event ID. Earthquake products deliverable to the CISN Display are ShakeMap, Ground Displacement, Focal Mechanisms, Rapid Notifications, OES Reports, and Earthquake Commentaries. Leveraging the power of the XML-format, the CISN Display provides prompt access to

  18. Critical fluid light scattering

    NASA Technical Reports Server (NTRS)

    Gammon, Robert W.

    1988-01-01

    The objective is to measure the decay rates of critical density fluctuations in a simple fluid (xenon) very near its liquid-vapor critical point using laser light scattering and photon correlation spectroscopy. Such experiments were severely limited on Earth by the presence of gravity which causes large density gradients in the sample when the compressibility diverges approaching the critical point. The goal is to measure fluctuation decay rates at least two decades closer to the critical point than is possible on earth, with a resolution of 3 microK. This will require loading the sample to 0.1 percent of the critical density and taking data as close as 100 microK to the critical temperature. The minimum mission time of 100 hours will allow a complete range of temperature points to be covered, limited by the thermal response of the sample. Other technical problems have to be addressed such as multiple scattering and the effect of wetting layers. The experiment entails measurement of the scattering intensity fluctuation decay rate at two angles for each temperature and simultaneously recording the scattering intensities and sample turbidity (from the transmission). The analyzed intensity and turbidity data gives the correlation length at each temperature and locates the critical temperature. The fluctuation decay rate data from these measurements will provide a severe test of the generalized hydrodynamic theories of transport coefficients in the critical regions. When compared to equivalent data from binary liquid critical mixtures they will test the universality of critical dynamics.

  19. Rapid detection of health-care-associated bloodstream infection in critical care using multipathogen real-time polymerase chain reaction technology: a diagnostic accuracy study and systematic review.

    PubMed Central

    Warhurst, Geoffrey; Dunn, Graham; Chadwick, Paul; Blackwood, Bronagh; McAuley, Daniel; Perkins, Gavin D; McMullan, Ronan; Gates, Simon; Bentley, Andrew; Young, Duncan; Carlson, Gordon L; Dark, Paul

    2015-01-01

    BACKGROUND There is growing interest in the potential utility of real-time polymerase chain reaction (PCR) in diagnosing bloodstream infection by detecting pathogen deoxyribonucleic acid (DNA) in blood samples within a few hours. SeptiFast (Roche Diagnostics GmBH, Mannheim, Germany) is a multipathogen probe-based system targeting ribosomal DNA sequences of bacteria and fungi. It detects and identifies the commonest pathogens causing bloodstream infection. As background to this study, we report a systematic review of Phase III diagnostic accuracy studies of SeptiFast, which reveals uncertainty about its likely clinical utility based on widespread evidence of deficiencies in study design and reporting with a high risk of bias. OBJECTIVE Determine the accuracy of SeptiFast real-time PCR for the detection of health-care-associated bloodstream infection, against standard microbiological culture. DESIGN Prospective multicentre Phase III clinical diagnostic accuracy study using the standards for the reporting of diagnostic accuracy studies criteria. SETTING Critical care departments within NHS hospitals in the north-west of England. PARTICIPANTS Adult patients requiring blood culture (BC) when developing new signs of systemic inflammation. MAIN OUTCOME MEASURES SeptiFast real-time PCR results at species/genus level compared with microbiological culture in association with independent adjudication of infection. Metrics of diagnostic accuracy were derived including sensitivity, specificity, likelihood ratios and predictive values, with their 95% confidence intervals (CIs). Latent class analysis was used to explore the diagnostic performance of culture as a reference standard. RESULTS Of 1006 new patient episodes of systemic inflammation in 853 patients, 922 (92%) met the inclusion criteria and provided sufficient information for analysis. Index test assay failure occurred on 69 (7%) occasions. Adult patients had been exposed to a median of 8 days (interquartile range 4

  20. Critics and Criticism of Education

    ERIC Educational Resources Information Center

    Ornstein, Allan C.

    1977-01-01

    Radical educational critics, such as Edgar Friedenberg, Paul Goodman, A. S. Neill, John Holt, Jonathan Kozol, Herbert Kohl, James Herndon, and Ivan Illich, have few constructive goals, no strategy for broad change, and a disdain for modernization and compromise. Additionally, these critics, says the author, fail to consider social factors related…

  1. Effectiveness of a sediment time critical removal action-PCB reduction in fish tissue, surface water, and sediment via wet excavation.

    PubMed

    Santini, Andrew D; King, Todd; Krawczyk, Keith; Kern, John W

    2015-01-01

    Documenting successful remediation of polychlorinated biphenyl (PCB)-contaminated sediments is limited; potentially due to inadequate monitoring methods, complexities associated with the environment, and selected remedial techniques. At some sites, absence of appropriate baseline and postremoval monitoring limits proper evaluation of remedial efficacy. Accurate interpretation of interactions between media, space, time, species, lipid content, and remedial technique requires robust study design and data. This article presents baseline and postremoval data documenting reduced PCB concentrations in fish tissue, surface water, and sediment in response to the US Environmental Protection Agency (USEPA) time-critical removal action (TCRA) that was conducted at the former Bryant Mill Pond (BMP) on Portage Creek in Kalamazoo, Michigan. The BMP is part of an operable unit (OU) within the Allied Paper, Inc./Portage Creek/Kalamazoo River Superfund Site. PCBs discharged to the creek as a byproduct of carbonless copy paper recycling are the primary contaminant of concern. Paper waste residuals commonly appear as gray to light gray clays in river sediments and floodplain soils. The cleanup criterion was 10 mg/kg, with a residual PCB concentration goal of 1 mg/kg. Because the PCB-containing waste is (generally) associated with readily visible light gray clay, excavation of all visibly contaminated current or formerly impounded sediment served as a surrogate for the cleanup criteria and goal. Sediment was wet excavated and backfilled after diversion of the creek. After confirmation that PCB concentrations met cleanup criteria, the stream was diverted to the excavated side, and excavation and backfilling were completed. Overall, 146000 cubic yards of material including PCB-contaminated sediments were removed from the BMP. The long-term monitoring (LTM) program implemented by the Michigan Department of Environmental Quality (MDEQ), and historic data from a variety of sources

  2. Rethinking Creative Teaching and Teaching as Research: Mapping the Critical Phases that Mark Times of Change and Choosing as Learners and Teachers of Music

    ERIC Educational Resources Information Center

    Burnard, Pamela

    2012-01-01

    This article describes the use of a visual-based construct elicitation tool developed from the use of critical incident charting for the purpose of reflecting on our creative learning journeys either at significant points as music learners in childhood, in adult life, or as preservice or experienced teachers. In this article, I introduce diverse…

  3. Quantum criticality of a spin-1 XY model with easy-plane single-ion anisotropy via a two-time Green function approach avoiding the Anderson-Callen decoupling

    NASA Astrophysics Data System (ADS)

    Mercaldo, M. T.; Rabuffo, I.; De Cesare, L.; Caramico D'Auria, A.

    2016-04-01

    In this work we study the quantum phase transition, the phase diagram and the quantum criticality induced by the easy-plane single-ion anisotropy in a d-dimensional quantum spin-1 XY model in absence of an external longitudinal magnetic field. We employ the two-time Green function method by avoiding the Anderson-Callen decoupling of spin operators at the same sites which is of doubtful accuracy. Following the original Devlin procedure we treat exactly the higher order single-site anisotropy Green functions and use Tyablikov-like decouplings for the exchange higher order ones. The related self-consistent equations appear suitable for an analysis of the thermodynamic properties at and around second order phase transition points. Remarkably, the equivalence between the microscopic spin model and the continuous O(2) -vector model with transverse-Ising model (TIM)-like dynamics, characterized by a dynamic critical exponent z=1, emerges at low temperatures close to the quantum critical point with the single-ion anisotropy parameter D as the non-thermal control parameter. The zero-temperature critic anisotropy parameter Dc is obtained for dimensionalities d > 1 as a function of the microscopic exchange coupling parameter and the related numerical data for different lattices are found to be in reasonable agreement with those obtained by means of alternative analytical and numerical methods. For d > 2, and in particular for d=3, we determine the finite-temperature critical line ending in the quantum critical point and the related TIM-like shift exponent, consistently with recent renormalization group predictions. The main crossover lines between different asymptotic regimes around the quantum critical point are also estimated providing a global phase diagram and a quantum criticality very similar to the conventional ones.

  4. The relevance of drug clearance to antibiotic dosing in critically ill patients.

    PubMed

    Roberts, Darren M

    2011-12-01

    To maximise the effect of an antibiotic it is necessary to pay careful attention to dosing. The maintenance dose is determined by antibiotic clearance which is usually determined in young healthy adults with normal physiology. Antibiotic clearance in critically ill patients may increase or decrease due to altered physiology and the treatments that are administered. Clearance may also vary significantly over time in patients with critical illness. Advancing age and comorbidities, in particular chronic kidney disease, can also decrease antibiotic clearance. Therefore, it is complicated and arguably impossible to suggest generic guidelines for the dosing of antibiotics in critically ill patients. Factors that influence clearance must be identified and accounted for in each patient for a rational approach to dose adjustment of antibiotics in patients with critical illness. The necessary changes can be predicted by understanding pharmacokinetic concepts. It is necessary to quantify organ function in patients at multiple time points because this can be used to estimate antibiotic clearance and guide dose selection. For example, creatinine clearance should be calculated but methods used in ambulatory patients may not apply to patients with critical illness. If possible, therapeutic drug monitoring should be conducted to ensure that antibiotic concentration targets are achieved and also to guide titration of subsequent doses. If blood sampling is carefully planned it may be possible to directly measure antibiotic clearance for dose adjustment. The purpose of this article is to review the concept of clearance and to highlight circumstances where antibiotic clearance may be altered in patients with critical illness. Strategies for dose modification of antibiotics in critically ill patients will be discussed. PMID:21554217

  5. Effectiveness of Automated Notification and Customer Service Call Centers for Timely and Accurate Reporting of Critical Values: A Laboratory Medicine Best Practices Systematic Review and Meta-Analysis

    PubMed Central

    Liebow, Edward B.; Derzon, James H.; Fontanesi, John; Favoretto, Alessandra M.; Baetz, Rich Ann; Shaw, Colleen; Thompson, Pamela; Mass, Diana; Christenson, Robert; Epner, Paul; Snyder, Susan R.

    2015-01-01

    Objective To conduct a systematic review of automatic notification methods and consider evidence-based recommendations for best practices in improving the timeliness and accuracy of critical value reporting. Results 196 bibliographic records were identified, with nine meeting review inclusion criteria. Four studies examined automated notification systems and five assessed call center performance. Average improvement from implementing automated notification systems is d = 0.42 (95% CI = 0.2 – 0.62) while the average odds ratio for call centers is OR = 22.1 (95% CI = 17.1 – 28.6). Conclusions The evidence, though suggestive, is not sufficient to make a recommendation for or against using automated notification systems as a best practice to improve the timeliness and accuracy of critical value reporting in an in-patient care setting. Call centers, however, are effective in improving the timeliness and accuracy of critical value reporting in an in-patient care setting, and are recommended as an “evidence-based best practice.” PMID:22750773

  6. Critical chemotactic collapse

    NASA Astrophysics Data System (ADS)

    Lushnikov, Pavel M.

    2010-04-01

    A Keller-Segel model describes macroscopic dynamics of bacterial colonies and biological cells as well as dynamics of a gas of self-gravitating Brownian particles. Bacteria secret chemical which attracts other bacteria so that they move towards chemical gradient creating nonlocal attraction between bacteria. If bacterial (or Brownian particle) density exceeds a critical value then the density collapses (blows up) in a finite time which corresponds to bacterial aggregation or gravitational collapse. Collapse in the Keller-Segel model has striking qualitative similarities with a nonlinear Schrödinger equation including critical collapse in two dimensions and supercritical collapse in three dimensions. A self-similar solution near blow up point is studied in the critical two-dimensional case and it has a form of a rescaled steady state solution which contains a critical number of bacteria. Time dependence of scaling of that solution has square root scaling law with logarithmic modification.

  7. Greening critical care

    PubMed Central

    2011-01-01

    Climate change and environmental stewardship are phrases that have been defining the past few decades and promoting change in our societies. The sensitivities of intensive care as a specialty make the process of greening an intensive care unit a challenge, but not one that is insurmountable. This paper discusses opportunities for critical care to reduce its environmental impact and provide a framework change. The article includes suggestions of what can be done as an individual, as a unit and as a hospital. Generally, practices in critical care are accepted without questioning the environmental consequences. We believe it is time for change, and critical care should give environmental stewardship a higher priority. PMID:21635700

  8. Mission Critical Networking

    SciTech Connect

    Eltoweissy, Mohamed Y.; Du, David H.C.; Gerla, Mario; Giordano, Silvia; Gouda, Mohamed; Schulzrinne, Henning; Youssef, Moustafa

    2010-06-01

    Mission-Critical Networking (MCN) refers to networking for application domains where life or livelihood may be at risk. Typical application domains for MCN include critical infrastructure protection and operation, emergency and crisis intervention, healthcare services, and military operations. Such networking is essential for safety, security and economic vitality in our complex world characterized by uncertainty, heterogeneity, emergent behaviors, and the need for reliable and timely response. MCN comprise networking technology, infrastructures and services that may alleviate the risk and directly enable and enhance connectivity for mission-critical information exchange among diverse, widely dispersed, mobile users.

  9. Critical Thinking

    ERIC Educational Resources Information Center

    Villano, Matt

    2006-01-01

    True excellence in technology implementation emerges when IT, administrative, and academic leaders link IT to mission-critical institutional objectives, investing in hardware and software to serve an explicit purpose and a distinct population of users. This article illustrates that at public institutions of higher education in New Hampshire as…

  10. District health planning at a time of transition: a critical review and lessons learnt from the implementation of regional planning in Uganda.

    PubMed

    Curtale, Filippo; Musila, Timothy; Opigo, Jimmy; Nantamu, Dyogo; Ezati, Isaac Alidria

    2016-05-01

    A quarter of a century after the Harare Declaration on Strengthening District Health Systems Based on Primary Health Care (1987) was conceived, district health teams (DHTs) are facing a markedly changed situation. Rapid population growth, urbanization, a rapidly developing private sector, and the increasing role of vertical programs and global initiatives have marginalized the planning process and weakened the entire district health system (DHS). The Ugandan Ministry of Health (MoH) responded to these challenges by beginning a review of district planning: a key action point of the Harare Declaration. The first step was a critical review of relevant literature, then central and district health staff were engaged with to provide their input in developing the new strategy. Through a field experiment started in 2012-13, and still underway, the MoH is developing an innovative regional approach to health planning, which aims to encompass the complexity of the new context of health care provision and coordinate all new actors (private health providers, projects and local government staff from other sectors) operating in the health sector. A strategic revision of the planning process represents an opportunity to develop an appropriate 'Theory of Change', intended as a broader approach of thinking about the entire DHS and the relative role and functions of the DHT. Leadership and stewardship capacities of MoH staff, at central and peripheral level, must be strengthened and supported to achieve the expected changes and results. PMID:27178674

  11. Uncommon Teaching in Commonsense Times: A Case Study of a Critical Multicultural Educator and the Academic Success of Diverse Student Populations

    ERIC Educational Resources Information Center

    Camp, Emilie M.; Oesterreich, Heather A.

    2010-01-01

    In an effort to explore the complexity of how teachers develop and sustain the ability to teach uncommonly in commonsense times, the authors conducted a life history case study of Rae, a fifth grade teacher at a local elementary school in the Southwest United States who has practiced and sustained uncommon teaching for four years. Combining…

  12. A Critical Analysis of the Role of Wait Time in Classroom Interactions and the Effects on Student and Teacher Interactional Behaviours

    ERIC Educational Resources Information Center

    Ingram, Jenni; Elliott, Victoria

    2016-01-01

    Extending the pauses between teachers' and students' turns (wait time) has been recommended as a way of improving classroom learning. Drawing on the Conversation Analysis literature on classroom interactions alongside extracts of classroom interactions, the relationship between these pauses and the interactional behaviour of teachers and students…

  13. Reviews/Essays: School Start Times and the Sleep-Wake Cycle of Adolescents--A Review and Critical Evaluation of Available Evidence

    ERIC Educational Resources Information Center

    Kirby, Matthew; Maggi, Stefania; D'Angiulli, Amedeo

    2011-01-01

    The authors have integrated the major findings on the sleep-wake cycle and its performance correlates in adolescents. Basic research shows that lack of synchronicity between early school start times and the circadian rhythm of adolescents (and the sleep debt accumulated as a result) involves several cognitive correlates that may harm the academic…

  14. Lung ultrasound in the critically ill

    PubMed Central

    2014-01-01

    Lung ultrasound is a basic application of critical ultrasound, defined as a loop associating urgent diagnoses with immediate therapeutic decisions. It requires the mastery of ten signs: the bat sign (pleural line), lung sliding (yielding seashore sign), the A-line (horizontal artifact), the quad sign, and sinusoid sign indicating pleural effusion, the fractal, and tissue-like sign indicating lung consolidation, the B-line, and lung rockets indicating interstitial syndrome, abolished lung sliding with the stratosphere sign suggesting pneumothorax, and the lung point indicating pneumothorax. Two more signs, the lung pulse and the dynamic air bronchogram, are used to distinguish atelectasis from pneumonia. All of these disorders were assessed using CT as the “gold standard” with sensitivity and specificity ranging from 90% to 100%, allowing ultrasound to be considered as a reasonable bedside “gold standard” in the critically ill. The BLUE-protocol is a fast protocol (<3 minutes), which allows diagnosis of acute respiratory failure. It includes a venous analysis done in appropriate cases. Pulmonary edema, pulmonary embolism, pneumonia, chronic obstructive pulmonary disease, asthma, and pneumothorax yield specific profiles. Pulmonary edema, e.g., yields anterior lung rockets associated with lung sliding, making the “B-profile.” The FALLS-protocol adapts the BLUE-protocol to acute circulatory failure. It makes sequential search for obstructive, cardiogenic, hypovolemic, and distributive shock using simple real-time echocardiography (right ventricle dilatation, pericardial effusion), then lung ultrasound for assessing a direct parameter of clinical volemia: the apparition of B-lines, schematically, is considered as the endpoint for fluid therapy. Other aims of lung ultrasound are decreasing medical irradiation: the LUCIFLR program (most CTs in ARDS or trauma can be postponed), a use in traumatology, intensive care unit, neonates (the signs are the same than

  15. Lung ultrasound in the critically ill.

    PubMed

    Lichtenstein, Daniel A

    2014-01-01

    Lung ultrasound is a basic application of critical ultrasound, defined as a loop associating urgent diagnoses with immediate therapeutic decisions. It requires the mastery of ten signs: the bat sign (pleural line), lung sliding (yielding seashore sign), the A-line (horizontal artifact), the quad sign, and sinusoid sign indicating pleural effusion, the fractal, and tissue-like sign indicating lung consolidation, the B-line, and lung rockets indicating interstitial syndrome, abolished lung sliding with the stratosphere sign suggesting pneumothorax, and the lung point indicating pneumothorax. Two more signs, the lung pulse and the dynamic air bronchogram, are used to distinguish atelectasis from pneumonia. All of these disorders were assessed using CT as the "gold standard" with sensitivity and specificity ranging from 90% to 100%, allowing ultrasound to be considered as a reasonable bedside "gold standard" in the critically ill. The BLUE-protocol is a fast protocol (<3 minutes), which allows diagnosis of acute respiratory failure. It includes a venous analysis done in appropriate cases. Pulmonary edema, pulmonary embolism, pneumonia, chronic obstructive pulmonary disease, asthma, and pneumothorax yield specific profiles. Pulmonary edema, e.g., yields anterior lung rockets associated with lung sliding, making the "B-profile." The FALLS-protocol adapts the BLUE-protocol to acute circulatory failure. It makes sequential search for obstructive, cardiogenic, hypovolemic, and distributive shock using simple real-time echocardiography (right ventricle dilatation, pericardial effusion), then lung ultrasound for assessing a direct parameter of clinical volemia: the apparition of B-lines, schematically, is considered as the endpoint for fluid therapy. Other aims of lung ultrasound are decreasing medical irradiation: the LUCIFLR program (most CTs in ARDS or trauma can be postponed), a use in traumatology, intensive care unit, neonates (the signs are the same than in adults

  16. Applying critical thinking to nursing.

    PubMed

    Price, Bob

    2015-08-19

    Critical thinking and writing are skills that are not easy to acquire. The term 'critical' is used differently in social and clinical contexts. Nursing students need time to master the inquisitive and ruminative aspects of critical thinking that are required in academic environments. This article outlines what is meant by critical thinking in academic settings, in relation to both theory and reflective practice. It explains how the focus of a question affects the sort of critical thinking required and offers two taxonomies of learning, to which students can refer when analysing essay requirements. The article concludes with examples of analytical writing in reference to theory and reflective practice. PMID:26285997

  17. Unmanned Aerial Vehicle (UAV) Dynamic-Tracking Directional Wireless Antennas for Low Powered Applications that Require Reliable Extended Range Operations in Time Critical Scenarios

    SciTech Connect

    Scott G. Bauer; Matthew O. Anderson; James R. Hanneman

    2005-10-01

    The proven value of DOD Unmanned Aerial Vehicles (UAVs) will ultimately transition to National and Homeland Security missions that require real-time aerial surveillance, situation awareness, force protection, and sensor placement. Public services first responders who routinely risk personal safety to assess and report a situation for emergency actions will likely be the first to benefit from these new unmanned technologies. ‘Packable’ or ‘Portable’ small class UAVs will be particularly useful to the first responder. They require the least amount of training, no fixed infrastructure, and are capable of being launched and recovered from the point of emergency. All UAVs require wireless communication technologies for real- time applications. Typically on a small UAV, a low bandwidth telemetry link is required for command and control (C2), and systems health monitoring. If the UAV is equipped with a real-time Electro-Optical or Infrared (EO/Ir) video camera payload, a dedicated high bandwidth analog/digital link is usually required for reliable high-resolution imagery. In most cases, both the wireless telemetry and real-time video links will be integrated into the UAV with unity gain omni-directional antennas. With limited on-board power and payload capacity, a small UAV will be limited with the amount of radio-frequency (RF) energy it transmits to the users. Therefore, ‘packable’ and ‘portable’ UAVs will have limited useful operational ranges for first responders. This paper will discuss the limitations of small UAV wireless communications. The discussion will present an approach of utilizing a dynamic ground based real-time tracking high gain directional antenna to provide extend range stand-off operation, potential RF channel reuse, and assured telemetry and data communications from low-powered UAV deployed wireless assets.

  18. Science education in Africa; A critical time for critical thinking.

    NASA Astrophysics Data System (ADS)

    Murabona, S.; Daka, O.; Chileshi, M.; Darrow, J.; Tung, A.; Wanless, E.; Hand, K.

    2005-12-01

    The change toward industrialization and a technologically advanced society is occurring at an ever increasing rate in developing regions of the world. Such change brings with it both the benefits of access to medicine, water, and food, and the negative effects of pollution, the destruction of natural resources, and the loss of both cultural and biological diversity. In many developing regions the human population is uneducated and incapable of playing an active role in the changes occurring around them. Here we discuss the work of our small non-profit, Cosmos Education, and our efforts to improve basic science education in sub-Saharan Africa. The mission of Cosmos Education is to foster global sustainable development through improved science and technology education in developing regions of the world. Our guiding vision is quite simple: Youth are the future. Education is the key. Cosmos Education aims to make a sustained and effective difference by working from the ground up - reaching individual students and teachers and making a difference in the classroom. We focus on science and technology education and the role of science and technology in health, the environment, and sustainable development. Our model is grassroots development from within; we want the youth in developing regions of the world to decide how their nations develop. In order to be able to do this, the youth must have the knowledge and skills needed to understand the rapidly changing world around them. They must be inspired, empowered, and engaged in their education. By working directly in classrooms, making learning fun with hands-on experiments, and providing the students with talented role-models from their own geographic region, we hope to excite students about their potential drive development from within and to catalyze development that will have a positive effect on the biosphere.

  19. Nuclear criticality information system

    SciTech Connect

    Koponen, B.L.; Hampel, V.E.

    1981-11-30

    The nuclear criticality safety program at LLNL began in the 1950's with a critical measurements program which produced benchmark data until the late 1960's. This same time period saw the rapid development of computer technology useful for both computer modeling of fissile systems and for computer-aided management and display of the computational benchmark data. Database management grew in importance as the amount of information increased and as experimental programs were terminated. Within the criticality safety program at LLNL we began at that time to develop a computer library of benchmark data for validation of computer codes and cross sections. As part of this effort, we prepared a computer-based bibliography of criticality measurements on relatively simple systems. However, it is only now that some of these computer-based resources can be made available to the nuclear criticality safety community at large. This technology transfer is being accomplished by the DOE Technology Information System (TIS), a dedicated, advanced information system. The NCIS database is described.

  20. Nanoscale grains, high irreversibility field and large critical current density as a function of high-energy ball milling time in C-doped magnesium diboride

    NASA Astrophysics Data System (ADS)

    Senkowicz, B. J.; Mungall, R. J.; Zhu, Y.; Jiang, J.; Voyles, P. M.; Hellstrom, E. E.; Larbalestier, D. C.

    2008-03-01

    Magnesium diboride (MgB2) powder was mechanically alloyed by high-energy ball milling with C to a composition of Mg(B0.95C0.05)2 and then sintered at 1000 °C in a hot isostatic press. Milling times varied from 1 to 3000 min. Full C incorporation required only 30-60 min of milling. The grain size of sintered samples decreased with increased milling time to <30 nm for 20-50 h of milling. Milling had a weak detrimental effect on the connectivity. A strong irreversibility field (H*) increase (from 13.3 to 17.2 T at 4.2 K) due to increased milling time was observed and correlated linearly with inverse grain size (1/d). As a result, the high-field Jc benefited greatly from lengthy powder milling. Jc (8 T, 4.2 K) peaked at>80 000 A cm-2 with 1200 min of milling compared with only ~26 000 A cm-2 for 60 min of milling. This non-compositional performance increase is attributed to grain refinement of the unsintered powder by milling, and to the probable suppression of grain growth by milling-induced MgO nanodispersions.

  1. Real-Time 3D Fluoroscopy-Guided Large Core Needle Biopsy of Renal Masses: A Critical Early Evaluation According to the IDEAL Recommendations

    SciTech Connect

    Kroeze, Stephanie G. C.; Huisman, Merel; Verkooijen, Helena M.; Diest, Paul J. van; Ruud Bosch, J. L. H.; Bosch, Maurice A. A. J. van den

    2012-06-15

    Introduction: Three-dimensional (3D) real-time fluoroscopy cone beam CT is a promising new technique for image-guided biopsy of solid tumors. We evaluated the technical feasibility, diagnostic accuracy, and complications of this technique for guidance of large-core needle biopsy in patients with suspicious renal masses. Methods: Thirteen patients with 13 suspicious renal masses underwent large-core needle biopsy under 3D real-time fluoroscopy cone beam CT guidance. Imaging acquisition and subsequent 3D reconstruction was done by a mobile flat-panel detector (FD) C-arm system to plan the needle path. Large-core needle biopsies were taken by the interventional radiologist. Technical success, accuracy, and safety were evaluated according to the Innovation, Development, Exploration, Assessment, Long-term study (IDEAL) recommendations. Results: Median tumor size was 2.6 (range, 1.0-14.0) cm. In ten (77%) patients, the histological diagnosis corresponded to the imaging findings: five were malignancies, five benign lesions. Technical feasibility was 77% (10/13); in three patients biopsy results were inconclusive. The lesion size of these three patients was <2.5 cm. One patient developed a minor complication. Median follow-up was 16.0 (range, 6.4-19.8) months. Conclusions: 3D real-time fluoroscopy cone beam CT-guided biopsy of renal masses is feasible and safe. However, these first results suggest that diagnostic accuracy may be limited in patients with renal masses <2.5 cm.

  2. Critical evaluation of screening techniques for emerging environmental contaminants based on accurate mass measurements with time-of-flight mass spectrometry.

    PubMed

    Nurmi, Joonas; Pellinen, Jukka; Rantalainen, Anna-Lea

    2012-03-01

    Emerging contaminants from wastewater effluent samples were analysed, using posttarget and nontarget analysis techniques. The samples were analysed with an ultra performance liquid chromatograph-time-of-flight mass spectrometer (UPLC-TOF-MS), and the resulting data were processed with commercial deconvolution software. The method works well for posttarget analysis with prior information about the retention times of the compounds of interest. With positive polarity, 63 of 66 compounds and with negative polarity, 18 of 20 compounds were correctly identified in a spiked sample, while two compounds of a total of 88 fell out of the mass range. Furthermore, a four-stage process for identification was developed for the posttarget analysis lacking the retention time data. In the process, the number of candidate compounds was reduced by using the accurate mass of selected compounds in two steps (stages 1 and 2), structure-property relationships (stage 3) and isotope patterns of the analytes (stage 4). The process developed was validated by analysing wastewater samples spiked with 88 compounds. This procedure can be used to gain a preliminary indication of the presence of certain analytes in the samples. Nontarget analysis was tested by applying a theoretical mass spectra library for a wastewater sample spiked with six pharmaceuticals. The results showed a high number of false identifications. In addition, manual processing of the data was considered laborious and ineffective. Finally, the posttarget analysis was applied to a real wastewater sample. The analysis revealed the presence of six compounds that were afterwards confirmed with standard compounds as being correct. Three psycholeptics (nordiazepam, oxazepam and temazepam) could be tentatively identified, using the identification process developed. Posttarget analysis with UPLC-TOF-MS proved to be a promising method for analysing wastewater samples, while we concluded that the software for nontarget analysis will need

  3. Prediction of critical illness in elderly outpatients using elder risk assessment: a population-based study

    PubMed Central

    Biehl, Michelle; Takahashi, Paul Y; Cha, Stephen S; Chaudhry, Rajeev; Gajic, Ognjen; Thorsteinsdottir, Bjorg

    2016-01-01

    Rationale Identifying patients at high risk of critical illness is necessary for the development and testing of strategies to prevent critical illness. The aim of this study was to determine the relationship between high elder risk assessment (ERA) score and critical illness requiring intensive care and to see if the ERA can be used as a prediction tool to identify elderly patients at the primary care visit who are at high risk of critical illness. Methods A population-based historical cohort study was conducted in elderly patients (age >65 years) identified at the time of primary care visit in Rochester, MN, USA. Predictors including age, previous hospital days, and comorbid health conditions were identified from routine administrative data available in the electronic medical record. The main outcome was critical illness, defined as sepsis, need for mechanical ventilation, or death within 2 years of initial visit. Patients with an ERA score of 16 were considered to be at high risk. The discrimination of the ERA score was assessed using area under the receiver operating characteristic curve. Results Of the 13,457 eligible patients, 9,872 gave consent for medical record review and had full information on intensive care unit utilization. The mean age was 75.8 years (standard deviation ±7.6 years), and 58% were female, 94% were Caucasian, 62% were married, and 13% were living in nursing homes. In the overall group, 417 patients (4.2%) suffered from critical illness. In the 1,134 patients with ERA >16, 154 (14%) suffered from critical illness. An ERA score ≥16 predicted critical illness (odds ratio 6.35; 95% confidence interval 3.51–11.48). The area under the receiver operating characteristic curve was 0.75, which indicated good discrimination. Conclusion A simple model based on easily obtainable administrative data predicted critical illness in the next 2 years in elderly outpatients with up to 14% of the highest risk population suffering from critical illness

  4. Survival of time-evolved quantum correlations depending on whether quenching is across a critical point in an X Y spin chain

    NASA Astrophysics Data System (ADS)

    Mishra, Utkarsh; Rakshit, Debraj; Prabhu, R.

    2016-04-01

    The time dynamics of quantum correlations in the quantum transverse anisotropic X Y spin chain of infinite length is studied at zero and finite temperatures. The evolution occurs due to the instantaneous quenching of the coupling constant between the nearest-neighbor spins of the model, which is performed either within the same phase or across the quantum phase-transition point connecting the order-disorder phases of the model. We characterize the time-evolved quantum correlations, viz., entanglement and quantum discord, which exhibit varying behavior depending on the initial state and the quenching scheme. We show that the system is endowed with enhanced nearest-neighbor bipartite quantum correlations compared to that of the initial state, when quenched from the ordered to the deep disordered phase. However, nearest-neighbor quantum correlations are almost washed out when the system is quenched from the disordered to the ordered phase with the initial state being at the zero temperature. We also identify the condition for the occurrence of enhanced bipartite correlations when the system is quenched within the same phase. Moreover, we investigate the bipartite quantum correlations when the initial state is a thermal equilibrium state with finite temperature, which reveals the effects of thermal fluctuation on the phenomena observed at zero temperature. Finally, an analogous analysis is carried out for zero-temperature next-nearest-neighbor quantum correlations.

  5. CISN Display Progress to Date - Reliable Delivery of Real-Time Earthquake Information, and ShakeMap to Critical End Users

    NASA Astrophysics Data System (ADS)

    Rico, H.; Hauksson, E.; Thomas, E.; Friberg, P.; Frechette, K.; Given, D.

    2003-12-01

    The California Integrated Seismic Network (CISN) has collaborated to develop a next-generation earthquake notification system that is nearing its first operations-ready release. The CISN Display actively alerts users of seismic data, and vital earthquake hazards information following a significant event. It will primarily replace the Caltech/USGS Broadcast of Earthquakes (CUBE) and Rapid Earthquake Data Integration (REDI) Display as the principal means of delivering geographical seismic data to emergency operations centers, utility companies and media outlets. A subsequent goal is to provide automated access to the many Web products produced by regional seismic networks after an earthquake. Another aim is to create a highly configurable client, allowing user organizations to overlay infrastructure data critical to their roles as first-responders, or lifeline operators. And the final goal is to integrate these requirements, into a package offering several layers of reliability to ensure delivery of services. Central to the CISN Display's role as a gateway to Web-based earthquake products is its comprehensive XML-messaging schema. The message model uses many of the same attributes in the CUBE format, but extends the old standard by provisioning additional elements for products currently available, and others yet to be considered. The client consumes these XML-messages, sorts them through a resident Quake Data Merge filter, and posts updates that also include hyperlinks associated to specific event IDs on the display map. Earthquake products available for delivery to the CISN Display are ShakeMap, focal mechanisms, waveform data, felt reports, aftershock forecasts and earthquake commentaries. By design the XML-message schema can evolve as products and information needs change, without breaking existing applications that rely on it. The latest version of the CISN Display can also automatically download ShakeMaps and display shaking intensity within the GIS system. This

  6. Critical points of DNA quantification by real-time PCR – effects of DNA extraction method and sample matrix on quantification of genetically modified organisms

    PubMed Central

    Cankar, Katarina; Štebih, Dejan; Dreo, Tanja; Žel, Jana; Gruden, Kristina

    2006-01-01

    Background Real-time PCR is the technique of choice for nucleic acid quantification. In the field of detection of genetically modified organisms (GMOs) quantification of biotech products may be required to fulfil legislative requirements. However, successful quantification depends crucially on the quality of the sample DNA analyzed. Methods for GMO detection are generally validated on certified reference materials that are in the form of powdered grain material, while detection in routine laboratories must be performed on a wide variety of sample matrixes. Due to food processing, the DNA in sample matrixes can be present in low amounts and also degraded. In addition, molecules of plant origin or from other sources that affect PCR amplification of samples will influence the reliability of the quantification. Further, the wide variety of sample matrixes presents a challenge for detection laboratories. The extraction method must ensure high yield and quality of the DNA obtained and must be carefully selected, since even components of DNA extraction solutions can influence PCR reactions. GMO quantification is based on a standard curve, therefore similarity of PCR efficiency for the sample and standard reference material is a prerequisite for exact quantification. Little information on the performance of real-time PCR on samples of different matrixes is available. Results Five commonly used DNA extraction techniques were compared and their suitability for quantitative analysis was assessed. The effect of sample matrix on nucleic acid quantification was assessed by comparing 4 maize and 4 soybean matrixes. In addition 205 maize and soybean samples from routine analysis were analyzed for PCR efficiency to assess variability of PCR performance within each sample matrix. Together with the amount of DNA needed for reliable quantification, PCR efficiency is the crucial parameter determining the reliability of quantitative results, therefore it was chosen as the primary

  7. The Timing of Neural Stem Cell-Based Virotherapy Is Critical for Optimal Therapeutic Efficacy When Applied With Radiation and Chemotherapy for the Treatment of Glioblastoma

    PubMed Central

    Tobias, Alex L.; Thaci, Bart; Auffinger, Brenda; Rincón, Esther; Balyasnikova, Irina V.; Kim, Chung Kwon; Han, Yu; Zhang, Lingjiao; Aboody, Karen S.; Ahmed, Atique U.

    2013-01-01

    Abstract Glioblastoma multiforme (GBM) remains fatal despite intensive surgical, radiotherapeutic, and chemotherapeutic interventions. Neural stem cells (NSCs) have been used as cellular vehicles for the transportation of oncolytic virus (OV) to therapeutically resistant and infiltrative tumor burdens throughout the brain. The HB1.F3-CD human NSC line has demonstrated efficacy as a cell carrier for the delivery of a glioma tropic OV CRAd-Survivin-pk7 (CRAd-S-pk7) in vitro and in animal models of glioma. At this juncture, no study has investigated the effectiveness of OV-loaded NSCs when applied in conjunction with the standard of care for GBM treatment, and therefore this study was designed to fill this void. Here, we show that CRAd-S-pk7-loaded HB1.F3-CD cells retain their tumor-tropic properties and capacity to function as in situ viral manufacturers in the presence of ionizing radiation (XRT) and temozolomide (TMZ). Furthermore, for the first time, we establish a logical experimental model that aims to recapitulate the complex clinical scenario for the treatment of GBM and tests the compatibility of NSCs loaded with OV. We report that applying OV-loaded NSCs together with XRT and TMZ can increase the median survival of glioma bearing mice by approximately 46%. Most importantly, the timing and order of therapeutic implementation impact therapeutic outcome. When OV-loaded NSCs are delivered prior to rather than after XRT and TMZ treatment, the median survival of mice bearing patient-derived GBM43 glioma xenografts is extended by 30%. Together, data from this report support the testing of CRAd-S-pk7-loaded HB1.F3-CD cells in the clinical setting and argue in favor of a multimodality approach for the treatment of patients with GBM. PMID:23926209

  8. The use of health care services: is illness the only motivator?

    PubMed

    Gould, S J

    1989-01-01

    Increasingly, consumer researchers and marketers have turned their attention to the marketing of health care services. In that vein, this paper addresses the question of what determines a consumer's use of these services. Through a review of relevant studies, an examination is made of such factors as illness, social and behavioral variables, and changing attitudes toward health, which have been prompted by various social movements. It is concluded that while illness is a critical factor in the use of health care services, other factors are playing an increasingly important role. Strategic marketing implications are offered as to how health care marketers should address the illness factor in the promotion and delivery of care services. Finally, future research directions are suggested which would help to define and gauge the role of illness in the consumption and strategic marketing of health care services. PMID:10303941

  9. Frequency of Pathogenic Paediatric Bacterial Meningitis in Mozambique: The Critical Role of Multiplex Real-Time Polymerase Chain Reaction to Estimate the Burden of Disease

    PubMed Central

    Nhantumbo, Aquino Albino; Cantarelli, Vlademir Vicente; Caireão, Juliana; Munguambe, Alcides Moniz; Comé, Charlotte Elizabeth; Pinto, Gabriela do Carmo; Zimba, Tomás Francisco; Mandomando, Inácio; Semá, Cynthia Baltazar; Dias, Cícero; Moraes, Milton Ozório; Gudo, Eduardo Samo

    2015-01-01

    Background In Sub-Saharan Africa, including Mozambique, acute bacterial meningitis (ABM) represents a main cause of childhood mortality. The burden of ABM is seriously underestimated because of the poor performance of culture sampling, the primary method of ABM surveillance in the region. Low quality cerebrospinal fluid (CSF) samples and frequent consumption of antibiotics prior to sample collection lead to a high rate of false-negative results. To our knowledge, this study is the first to determine the frequency of ABM in Mozambique using real-time polymerase chain reaction (qPCR) and to compare results to those of culture sampling. Method Between March 2013 and March 2014, CSF samples were collected at 3 regional hospitals from patients under 5 years of age, who met World Health Organization case definition criteria for ABM. Macroscopic examination, cytochemical study, culture, and qPCR were performed on all samples. Results A total of 369 CSF samples were collected from children clinically suspected of ABM. qPCR showed a significantly higher detection rate of ABM-causing pathogens when compared to culture (52.3% [193/369] versus 7.3% [27/369], p = 0.000). The frequency of Streptococcus pneumoniae, Haemophilus influenzae, group B Streptococci, and Neisseria meningitidis were 32.8% (121⁄369), 12.2%, (45⁄369), 3.0% (16⁄369) and 4.3% (11⁄369), respectively, significantly higher compared to that obtained on culture (p < 0.001 for each). Conclusion Our findings demonstrate that culture is less effective for the diagnosis of ABM than qPCR. The common use of culture rather than qPCR to identify ABM results in serious underestimation of the burden of the disease, and our findings strongly suggest that qPCR should be incorporated into surveillance activities for ABM. In addition, our data showed that S. pneumoniae represents the most common cause of ABM in children under 5 years of age. PMID:26393933

  10. Critical Assessment of Time-Dependent Density Functional Theory for Excited States of Open-Shell Systems: II. Doublet-Quartet Transitions.

    PubMed

    Li, Zhendong; Liu, Wenjian

    2016-06-14

    Compared with closed-shell systems, open-shell systems place three additional challenges to time-dependent density functional theory (TD-DFT) for electronically excited states: (a) the spin-contamination problem is a serious issue; (b) the exchange-correlation (XC) kernel may be numerically instable; and (c) the single-determinant description of open-shell ground states readily becomes energetically instable. Confined to flip-up single excitations, the spin-contamination problem can largely be avoided by using the spin-flip TD-DFT (SF-TD-DFT) formalism, provided that a noncollinear XC kernel is employed. As for the numerical instabilities associated with such a kernel, only an ad hoc scheme has been proposed so far, viz., the ALDA0 kernel, which amounts to setting the divergent components (arising from density gradients and kinetic energy density) simply to zero. The ground-state instability problem can effectively be avoided by introducing the Tamm-Dancoff approximation (TDA) to TD-DFT. Therefore, on a general basis, the SF-TDA/ALDA0 Ansatz is so far the only promising means within the TD-DFT framework for flip-up single excitations of open-shell systems. To assess systematically the performance of SF-TDA/ALDA0, in total 61 low-lying quartet excited states of the benchmark set of 11 small radicals [J. Chem. Theory Comput. 2016, 12, 238] are investigated with various XC functionals. Taking the MRCISD+Q (multireference configuration interaction with singles and doubles plus the Davidson correction) results as benchmark, it is found that the mean absolute errors of SF-TDA/ALDA0 with the SAOP (statistical averaging of model orbital potentials), global hybrid, and range-separated hybrid functionals are in the range of 0.2-0.4 eV. This is in line not only with the typical accuracy of TD-DFT for singlet and triplet excited states of closed-shell systems but also with the gross accuracy of spin-adapted TD-DFT for spin-conserving excited states of open-shell systems. PMID

  11. Critical Pedagogy for Critical Mathematics Education

    ERIC Educational Resources Information Center

    Tutak, Fatma Aslan; Bondy, Elizabeth; Adams, Thomasenia L.

    2011-01-01

    This article provides a brief introduction to critical pedagogy and further discussion on critical mathematics education. Critical mathematics education enables students to read the world with mathematics. Three emerging domains of mathematics education related to critical mathematics education are discussed in this manuscript: ethnomathematics,…

  12. CCSDS Time-Critical Onboard Networking Service

    NASA Technical Reports Server (NTRS)

    Parkes, Steve; Schnurr, Rick; Marquart, Jane; Menke, Greg; Ciccone, Massimiliano

    2006-01-01

    The Consultative Committee for Space Data Systems (CCSDS) is developing recommendations for communication services onboard spacecraft. Today many different communication buses are used on spacecraft requiring software with the same basic functionality to be rewritten for each type of bus. This impacts on the application software resulting in custom software for almost every new mission. The Spacecraft Onboard Interface Services (SOIS) working group aims to provide a consistent interface to various onboard buses and sub-networks, enabling a common interface to the application software. The eventual goal is reusable software that can be easily ported to new missions and run on a range of onboard buses without substantial modification. The system engineer will then be able to select a bus based on its performance, power, etc and be confident that a particular choice of bus will not place excessive demands on software development. This paper describes the SOIS Intra-Networking Service which is designed to enable data transfer and multiplexing of a variety of internetworking protocols with a range of quality of service support, over underlying heterogeneous data links. The Intra-network service interface provides users with a common Quality of Service interface when transporting data across a variety of underlying data links. Supported Quality of Service (QoS) elements include: Priority, Resource Reservation and Retry/Redundancy. These three QoS elements combine and map into four TCONS services for onboard data communications: Best Effort, Assured, Reserved, and Guaranteed. Data to be transported is passed to the Intra-network service with a requested QoS. The requested QoS includes the type of service, priority and where appropriate, a channel identifier. The data is de-multiplexed, prioritized, and the required resources for transport are allocated. The data is then passed to the appropriate data link for transfer across the bus. The SOIS supported data links may inherently provide the quality of service support requested by the intra-network layer. In the case where the data link does not have the required level of support, the missing functionality is added by SOIS. As a result of this architecture, re-usable software applications can be designed and used across missions thereby promoting common mission operations. In addition, the protocol multiplexing function enables the blending of multiple onboard networks. This paper starts by giving an overview of the SOIS architecture in section 11, illustrating where the TCONS services fit into the overall architecture. It then describes the quality of service approach adopted, in section III. The prototyping efforts that have been going on are introduced in section JY. Finally, in section V the current status of the CCSDS recommendations is summarized.

  13. Tailored Treatment for HIV+ Persons with Mental Illness: The Intervention Cascade

    PubMed Central

    Blank, Michael; Eisenberg, Marlene

    2013-01-01

    The public health literature demonstrates disturbingly high HIV risk for persons with a serious mental illness (SMI), who are concurrently co-morbid for substance abuse (SA). Many HIV positives have not been tested, and therefore do not know their status, but for individuals who are triply diagnosed, adherence to HIV treatment results in meaningful reductions in viral loads and CD4 counts. Barriers to treatment compliance are reviewed, low threshold/low intensity community based interventions are discussed, and preliminary evidence is presented for the efficacy of the Intervention Cascade, defined as an integrated intervention delivered by specially trained nurses who individualize a treatment compliance intervention in real time as an adaptive response to demand characteristics of the individual. PMID:23673886

  14. Addressing Public Stigma and Disparities Among Persons With Mental Illness: The Role of Federal Policy

    PubMed Central

    Lucas, Stephen M.; Druss, Benjamin G.

    2013-01-01

    Stigma against mental illness is a complex construct with affective, cognitive, and behavioral components. Beyond its symbolic value, federal law can only directly address one component of stigma: discrimination. This article reviews three landmark antidiscrimination laws that expanded protections over time for individuals with mental illness. Despite these legislative advances, protections are still not uniform for all subpopulations with mental illness. Furthermore, multiple components of stigma (e.g., prejudice) are beyond the reach of legislation, as demonstrated by the phenomenon of label avoidance; individuals may not seek protection from discrimination because of fear of the stigma that may ensue after disclosing their mental illness. To yield the greatest improvements, antidiscrimination laws must be coupled with antistigma programs that directly address other components of stigma. PMID:23488484

  15. The Sick and the Weak: Neuropathies/Myopathies in the Critically Ill

    PubMed Central

    Friedrich, O.; Reid, M. B.; Van den Berghe, G.; Vanhorebeek, I.; Hermans, G.; Rich, M. M.; Larsson, L.

    2015-01-01

    Critical illness polyneuropathies (CIP) and myopathies (CIM) are common complications of critical illness. Several weakness syndromes are summarized under the term intensive care unit-acquired weakness (ICUAW). We propose a classification of different ICUAW forms (CIM, CIP, sepsis-induced, steroid-denervation myopathy) and pathophysiological mechanisms from clinical and animal model data. Triggers include sepsis, mechanical ventilation, muscle unloading, steroid treatment, or denervation. Some ICUAW forms require stringent diagnostic features; CIM is marked by membrane hypoexcitability, severe atrophy, preferential myosin loss, ultrastructural alterations, and inadequate autophagy activation while myopathies in pure sepsis do not reproduce marked myosin loss. Reduced membrane excitability results from depolarization and ion channel dysfunction. Mitochondrial dysfunction contributes to energy-dependent processes. Ubiquitin proteasome and calpain activation trigger muscle proteolysis and atrophy while protein synthesis is impaired. Myosin loss is more pronounced than actin loss in CIM. Protein quality control is altered by inadequate autophagy. Ca2+ dysregulation is present through altered Ca2+ homeostasis. We highlight clinical hallmarks, trigger factors, and potential mechanisms from human studies and animal models that allow separation of risk factors that may trigger distinct mechanisms contributing to weakness. During critical illness, altered inflammatory (cytokines) and metabolic pathways deteriorate muscle function. ICUAW prevention/treatment is limited, e.g., tight glycemic control, delaying nutrition, and early mobilization. Future challenges include identification of primary/secondary events during the time course of critical illness, the interplay between membrane excitability, bioenergetic failure and differential proteolysis, and finding new therapeutic targets by help of tailored animal models. PMID:26133937

  16. [Stigmatization on the way to recovery in mental illness - the factors associated with social functioning].

    PubMed

    Podogrodzka-Niell, Magdalena; Tyszkowska, Magdalena

    2014-01-01

    Persons with mental disorders often experience stigmatization. There is a number of social factors that may affect the process of recovery and at the same time, in certain circumstances, could be a source of stigma. Mentally ill may find strength in themselves to fight against the disease or the opposite - can internalize the negative attitudes of the society and become self-stigmatized. The patient's family, on the one hand, is often the only source of social support, on the other hand, can experience a destructive influence of courtesy-stigma. Mentally ill have to face social reluctance which is reinforced by stereotypical media coverage of mental disorders. The social network of patients is poor and often limited to a family system. Negative views about persons diagnosed with mental illness are most visible in the labour market. Patients experience many types of discrimination at work,have lower employment rates and lower mean wages than healthy ones. Structural discrimination is a form of stigma which is revealed in underfunded and inefficient system of mental health care. All the social factors mentioned above are necessary for recovery (positive stimulation of functioning), but can also increase stigma and become a significant barrier in the recovery of psychiatric patients. This paper highlights the complex and ambiguous nature of the relationship between social factors and the recovery of the mentally ill basing on the data from the literature. PMID:25717489

  17. Alerting of Laboratory Critical Values

    NASA Astrophysics Data System (ADS)

    Song, Sang Hoon; Park, Kyoung Un; Song, Junghan; Paik, Hyeon Young; Lee, Chi Woo; Bang, Su Mi; Hong, Joon Seok; Lee, Hyun Joo; Cho, In-Sook; Kim, Jeong Ah; Kim, Hyun-Young; Kim, Yoon

    Critical value is defined as a result suggesting that the patient is in danger unless appropriate action is taken immediately. We designed an automated reporting system of critical values and evaluated its performance. Fifteen critical values were defined and 2-4 doctors were assigned to receive short message service (SMS).Laboratory results in LIS and EMR were called back to the DIA server. The rule engine named U-brain in the CDSS server was run in real-time and decision if the laboratory data was critical was made. The CDSS system for alerting of laboratory critical values was fast and stable without additional burden to the entire EMR system. Continuous communication with clinicians and feedback of clinical performance are mandatory for the refinement and development of user-friendly CDSS contents. Appropriate clinical parameters are necessary for demonstration of the usefulness of the system.

  18. Early Psychological Therapy in Critical Illness.

    PubMed

    Karnatovskaia, Lioudmila V; Philbrick, Kemuel L; Parker, Ann M; Needham, Dale M

    2016-02-01

    Survivors of critical illness often experience long-lasting impairments in mental, cognitive, and physical functioning. Acute stress reactions and delusional memories appear to play an important role in psychological morbidity following critical illness, and few interventions exist to address these symptoms. This review elucidates acute psychological stressors experienced by the critically ill. The effects of psychological stress and state of mind on disease are discussed using examples from the non-intensive care unit (ICU) literature, including a review of placebo and nocebo effects. After reviewing the effect of the mind on both psychological and physiological outcomes, we then focus on the role of memories-including their malleable nature and the consequences of false memories. Memory may play a role in the genesis of subsequent psychological trauma. Traumatic memories may begin forming even before the patient arrives in the ICU and during their state of unconsciousness in the ICU. Hence, practical interventions for redirecting patients' thoughts, such as positive suggestion techniques and actively involving patients in the treatment process as early as possible, are worthy of further investigation. PMID:26820280

  19. Frailty in Pulmonary and Critical Care Medicine.

    PubMed

    Singer, Jonathan P; Lederer, David J; Baldwin, Matthew R

    2016-08-01

    Conceptualized first in the field of geriatrics, frailty is a syndrome characterized by a generalized vulnerability to stressors resulting from an accumulation of physiologic deficits across multiple interrelated systems. This accumulation of deficits results in poorer functional status and disability. Frailty is a "state of risk" for subsequent disproportionate declines in health status following new exposure to a physiologic stressor. Two predominant models have emerged to operationalize the measurement of frailty. The phenotype model defines frailty as a distinct clinical syndrome that includes conceptual domains such as strength, activity, wasting, and mobility. The cumulative deficit model defines frailty by enumerating the number of age-related things wrong with a person. The biological pathways driving frailty include chronic systemic inflammation, sarcopenia, and neuroendocrine dysregulation, among others. In adults with chronic lung disease, frailty is independently associated with more frequent exacerbations of lung disease, all-cause hospitalization, declines in functional status, and all-cause mortality. In addition, frail adults who become critically ill are more likely develop chronic critical illness or severe disability and have higher in-hospital and long-term mortality rates. The evaluation of frailty appears to provide important prognostic information above and beyond routinely collected measures in adults with chronic lung disease and the critically ill. The study of frailty in these populations, however, requires multipronged efforts aimed at refining clinical assessments, understanding the mechanisms, and developing therapeutic interventions. PMID:27104873

  20. Gradient liquid chromatographic retention time prediction for suspect screening applications: A critical assessment of a generalised artificial neural network-based approach across 10 multi-residue reversed-phase analytical methods.

    PubMed

    Barron, Leon P; McEneff, Gillian L

    2016-01-15

    For the first time, the performance of a generalised artificial neural network (ANN) approach for the prediction of 2492 chromatographic retention times (tR) is presented for a total of 1117 chemically diverse compounds present in a range of complex matrices and across 10 gradient reversed-phase liquid chromatography-(high resolution) mass spectrometry methods. Probabilistic, generalised regression, radial basis function as well as 2- and 3-layer multilayer perceptron-type neural networks were investigated to determine the most robust and accurate model for this purpose. Multi-layer perceptrons most frequently yielded the best correlations in 8 out of 10 methods. Averaged correlations of predicted versus measured tR across all methods were R(2)=0.918, 0.924 and 0.898 for the training, verification and test sets respectively. Predictions of blind test compounds (n=8-84 cases) resulted in an average absolute accuracy of 1.02±0.54min for all methods. Within this variation, absolute accuracy was observed to marginally improve for shorter runtimes, but was found to be relatively consistent with respect to analyte retention ranges (~5%). Finally, optimised and replicated network dependency on molecular descriptor data is presented and critically discussed across all methods. Overall, ANNs were considered especially suitable for suspects screening applications and could potentially be utilised in bracketed-type analyses in combination with high resolution mass spectrometry. PMID:26592605

  1. Critical Care Team

    MedlinePlus

    ... Please enable scripts and reload this page. About Critical Care Currently selected Team Questions During the ICU Chronic ... Team Currently selected Questions Patients and Families > About Critical Care > Team Tweet Team Page Content ​The critical care ...

  2. Critical Materials Institute

    SciTech Connect

    Alex King

    2013-01-09

    Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

  3. Critical Materials Institute

    ScienceCinema

    Alex King

    2013-06-05

    Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

  4. Critical Pedagogy for Transformative Optimism

    ERIC Educational Resources Information Center

    Mayo, Peter

    2006-01-01

    This essay critically highlights the main features of a study that attaches importance to the concepts of time and optimism and their effects on the achievement and goals of high and low achievers in a North American and a Brazilian context. The focus on the time factor that serves as a leitmotif throughout the study gives this work its…

  5. Adaptive critics for dynamic optimization.

    PubMed

    Kulkarni, Raghavendra V; Venayagamoorthy, Ganesh Kumar

    2010-06-01

    A novel action-dependent adaptive critic design (ACD) is developed for dynamic optimization. The proposed combination of a particle swarm optimization-based actor and a neural network critic is demonstrated through dynamic sleep scheduling of wireless sensor motes for wildlife monitoring. The objective of the sleep scheduler is to dynamically adapt the sleep duration to node's battery capacity and movement pattern of animals in its environment in order to obtain snapshots of the animal on its trajectory uniformly. Simulation results show that the sleep time of the node determined by the actor critic yields superior quality of sensory data acquisition and enhanced node longevity. PMID:20223635

  6. Critical Learning Skills for Business Students

    ERIC Educational Resources Information Center

    Jance, Marsha; Morgan, Anita

    2013-01-01

    A survey addressing critical skills for business students was developed and disseminated. Sixteen critical skills (such as critical thinking and time management) were identified as skills that need to be acquired in order for business students to be successful in their advanced courses and careers. The survey was disseminated and taken by several…

  7. Toward Superconducting Critical Current by Design.

    PubMed

    Sadovskyy, Ivan A; Jia, Ying; Leroux, Maxime; Kwon, Jihwan; Hu, Hefei; Fang, Lei; Chaparro, Carlos; Zhu, Shaofei; Welp, Ulrich; Zuo, Jian-Min; Zhang, Yifei; Nakasaki, Ryusuke; Selvamanickam, Venkat; Crabtree, George W; Koshelev, Alexei E; Glatz, Andreas; Kwok, Wai-Kwong

    2016-06-01

    A new critical-current-by-design paradigm is presented. It aims at predicting the optimal defect landscape in superconductors for targeted applications by elucidating the vortex dynamics responsible for the bulk critical current. To this end, critical current measurements on commercial high-temperature superconductors are combined with large-scale time-dependent Ginzburg-Landau simulations of vortex dynamics. PMID:27030115

  8. Nuclear criticality safety guide

    SciTech Connect

    Pruvost, N.L.; Paxton, H.C.

    1996-09-01

    This technical reference document cites information related to nuclear criticality safety principles, experience, and practice. The document also provides general guidance for criticality safety personnel and regulators.

  9. Design of Critical Components

    NASA Technical Reports Server (NTRS)

    Hendricks, Robert C.; Zaretsky, Erwin V.

    2001-01-01

    Critical component design is based on minimizing product failures that results in loss of life. Potential catastrophic failures are reduced to secondary failures where components removed for cause or operating time in the system. Issues of liability and cost of component removal become of paramount importance. Deterministic design with factors of safety and probabilistic design address but lack the essential characteristics for the design of critical components. In deterministic design and fabrication there are heuristic rules and safety factors developed over time for large sets of structural/material components. These factors did not come without cost. Many designs failed and many rules (codes) have standing committees to oversee their proper usage and enforcement. In probabilistic design, not only are failures a given, the failures are calculated; an element of risk is assumed based on empirical failure data for large classes of component operations. Failure of a class of components can be predicted, yet one can not predict when a specific component will fail. The analogy is to the life insurance industry where very careful statistics are book-kept on classes of individuals. For a specific class, life span can be predicted within statistical limits, yet life-span of a specific element of that class can not be predicted.

  10. Critical Thinking Skills.

    ERIC Educational Resources Information Center

    Word's Worth: A Quarterly Newsletter of the Lifelong Learning Network, 1998

    1998-01-01

    This issue of a quarterly newsletter focuses on the theme of critical thinking skills. "Critical Thinking Skills: An Interview with Dr. Richard Paul" (Barbara Christopher) is the text of an interview in which the director of research at Sonoma State University's Center for Critical Thinking examines the meaning of critical thinking and the ways…