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Early Warning (early + warning)
Terms modified by Early Warning Selected AbstractsError-correction methods and evaluation of an ensemble based hydrological forecasting system for the Upper Danube catchmentATMOSPHERIC SCIENCE LETTERS, Issue 2 2008K. Bogner Abstract Within the EU Project PREVention, Information and Early Warning (PREVIEW), ensembles of discharge series have been generated for the Danube catchment by the use of various weather forecast products. Hydrological models applied for streamflow prediction often have simulation errors that degrade forecast quality and limit the operational usefulness of the forecasts. Therefore, error-correction methods have been tested for adjusting the ensemble traces using a transformation derived with simulated and observed flows. This article presents first results of the combination of state-space models and wavelet transformations in order to update errors between the simulated (forecasted) and the observed discharge. Copyright © 2008 Royal Meteorological Society [source] Cultural-historical activity theory as practice theory: illuminating the development of conflict-monitoring networkCOMMUNICATION THEORY, Issue 1 2001Kirsten A. Foot As the number and intensity of conflicts increased around the world during the latter part of the 20th century, scholars, policymakers, and practitioners of non-violent conflict management strategies created conflict-monitoring networks to track the escalation of tensions in conflict-prone regions. This essay demonstrates how cultural-historical activity theory (CHAT) was employed in the service of a conflict-monitoring network in the former Soviet Union. Based upon historical and participant observation research on the development of the Network for Ethnological Monitoring and Early Warning during 1990,1999, a CHAT-based analysis of the Network's systemic contradictions illuminates its development through one expansive cycle and into a second. Summaries of findings consider relations within the Network, the evolution of the Network's complex object, and the Network's development of tools for monitoring ethnic relations and building an epistemic community. The essay concludes with an analysis of the correspondence between the CHAT framework and the 5 features of practical theory laid out by Cronen (1995). [source] Early warning of agglomeration in fluidized beds by attractor comparisonAICHE JOURNAL, Issue 11 2000J. Ruud van Ommen An enhanced monitoring method, based on pressure fluctuation measurements, for observing nonstationarities in fluidized-bed hydrodynamics is presented. Experiments show that it can detect small changes in the particle-size distribution. Such a monitoring method is useful to give an early warning of the onset of agglomeration in a fluidized bed. In contrast to earlier methods, this method is insensitive to small changes in superficial gas velocity and can handle multiple signals, making it relevant to industrial application. By carefully choosing the measurement position, the method becomes also insensitive to small bed mass variations. It uses the attractor reconstructed from a measured pressure signal, which is a "fingerprint" of the hydrodynamics of the fluidized bed for a certain set of conditions. Using this method statistically the reconstructed attractor of a reference time series of pressure fluctuations (representing the desired fluidization behavior) is compared with that of successive time series measured during the bed operation. [source] Getting the Scale Right: A Comparison of Analytical Methods for Vulnerability Assessment and Household-level TargetingDISASTERS, Issue 2 2001Linda Stephen This paper introduces broad concepts of vulnerability, food security and famine. It argues that the concepts and theories driving development and implementation of vulnerability assessment tools are related to their utility. The review concludes that socio-geographic scale is a key issue, and challenge. It analyses three vulnerability assessment (VA) methods, using Ethiopia as a case study. Facing the challenges of vulnerability assessment and early warning requires providing accurate information at the required scale, useful for multiple decision-makers within realistic institutional capacities. [source] Expected loss-based alarm threshold set for earthquake early warning systemsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 9 2007Iunio Iervolino Abstract Earthquake early warning systems (EEWS) seem to have potential as tools for real-time seismic risk management and mitigation. In fact, although the evacuation of buildings requires warning time not available in many urbanized areas threatened by seismic hazard, they may still be used for the real-time protection of critical facilities using automatic systems in order to reduce the losses subsequent to a catastrophic event. This is possible due to the real-time seismology, which consists of methods and procedures for the rapid estimation of earthquake features, as magnitude and location, based on measurements made on the first seconds of the P -waves. An earthquake engineering application of earthquake early warning (EEW) may be intended as a system able to issue the alarm, if some recorded parameter exceeds a given threshold, to activate risk mitigation actions before the quake strikes at a site of interest. Feasibility analysis and design of such EEWS require the assessment of the expected loss reduction due to the security action and set of the alarm threshold. In this paper a procedure to carry out these tasks in the performance-based earthquake engineering probabilistic framework is proposed. A merely illustrative example refers to a simple structure assumed to be a classroom. Structural damage and non-structural collapses are considered; the security action is to shelter occupants below the desks. The cost due to a false alarm is assumed to be related to the interruption of didactic activities. Results show how the comparison of the expected losses, for the alarm-issuance and non-issuance cases, allows setting the alarm threshold on a quantitative and consistent basis, and how it may be a tool for the design of engineering applications of EEW. Copyright © 2007 John Wiley & Sons, Ltd. [source] Dental fluorosis in primary teeth: a study in rural schoolchildren in Shaanxi Province, ChinaINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 6 2005J. P. RUAN Summary. Objective. The aim of this study was to assess the prevalence and severity of fluorosis in the primary dentition of 7,8-year-old Chinese schoolchildren in areas with fluoride concentrations in the drinking water ranging from 0·35 to 7·6 mg L,1. Subjects and methods. Four hundred and seventy-two children from 13 different schools were divided into four groups according to the fluoride concentration of the drinking water: (A) , 1·0 mg L,1; (B) 1·1,2·0 mg L,1; (C) 2·1,3·8 mg L,1; and (D) 7·6 mg L,1. Clinical examinations were made under field conditions, and dental fluorosis on the buccal surfaces of all teeth was recorded using the Thylstrup,Fejerskov Index (TFI). Results. The prevalence of dental fluorosis in primary teeth varied from 6·2% to 96·6% according to the fluoride concentration of the drinking water. The differences of median of TFI scores between all groups were statistically significant (P < 0·001) except for groups B and C. No statistically significant difference in the severity of dental fluorosis was observed between genders. The second primary molars were most severely affected by dental fluorosis. Disregarding group A, TFI scores between 3 and 4 were most frequently recorded. Dental fluorosis was symmetrically distributed in both jaws. Conclusion. Dental fluorosis is prevalent in the primary teeth of children living in areas supplied with drinking water with fluoride concentrations higher than 1·0 mg L,1. The primary teeth may act as biomarkers of fluoride exposure. The examination of primary teeth may give an early warning of this condition, and thus, provide a basis for intervention to prevent dental fluorosis in the permanent teeth. [source] Assessing the Information Content of Mark-to-Market Accounting with Mixed Attributes: The Case of Cash Flow HedgesJOURNAL OF ACCOUNTING RESEARCH, Issue 2 2007FRANK GIGLER ABSTRACT We examine how outsiders rationally interpret a reported loss on derivatives when the application of mark-to-market accounting to cash flow hedges creates a mixed attribute problem. We find that because of the mixed attribute problem, the information content of mark-to-market accounting is related to the information content of historical cost accounting in a very specific way. This relationship allows us to identify the circumstances under which mark-to-market accounting facilitates and when it detracts from the objective of providing an early warning of potential financial distress. We show that the reporting of an impending derivative loss by a distressed firm can actually lead outsiders to infer that the firm is in a better financial position than what they would have inferred under the silence associated with historical cost accounting. Without the mixed attribute problem, mark-to-market accounting would always yield more accurate assessments of the firm's financial position. [source] Cross-talk involving extracellular sensors and extracellular alarmones gives early warning to unstressed Escherichia coli of impending lethal chemical stress and leads to induction of tolerance responsesJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2001R.J. Rowbury 1. Summary, 678 2. Introduction 2.1. Chemical and biological stress agents affecting enterobacteria, 678 2.2. Sensing of chemical and biological stress stimuli, 678 2.3. Intracellular sensors detect intracellularly-produced chemical stressing agents, 679 2.4. Intracellular sensors and intracellular induction components could delay response induction by extracellular chemical or biological stress agents, 680 2.5. Extracellular sensors and EICs give early warning of stress, 681 2.6. Disadvantages of extracellular components being needed for stress response induction, 682 2.7. Extracellular sensors and EICs allow stressed cells to warn unstressed ones, 682 2.8. A second role for some extracellular stress sensors, 683 3. Responses switched on by extracellular sensors and EICs 3.1. Involvement of EICs and ESCs in acid tolerance induction at pH 5·0 and at other mildly acidic pH values, 683 3.2. Further evidence for the obligate involvement of extracellular sensors and EICs in acid tolerance induction at pH 5·0, 684 3.3. On the nature of the acid pH tolerance-inducing ESC and EIC, 686 3.4. The acid tolerance ECs and their relation to other extracellular response-inducing components, 686 3.5. Extracellular components are needed for other inducible acid tolerance responses, 687 3.6. Involvement of EICs and extracellular sensors in acid tolerance in E. coli O157, 687 3.7. EICs involved in acid tolerance induction are diffusible, 687 4. Acid sensitization at alkaline pH and the role of extracellular sensor and EIC(s), 688 5. Responses affecting tolerance to alkali 5.1. Alkali sensitization at acidic pH, 688 5.2. Induced alkali tolerance at pH 9·0 and role of extracellular components, 688 6. Inducible tolerance to alkylhydroperoxides, 689 7. Are extracellular sensors and extracellular induction components needed for all stress responses?, 689 8. Altered responsiveness of extracellular sensors depending on growth conditions, 691 9. Protection of living cells from chemical stress by dead cultures, 691 10. How can intracellular levels of stress be detected?, 692 11. Are Nikolaev's extracellular ,protectants' and similar components related to EICs?, 693 12. Conclusions, 693 13. References, 694 [source] Drought Preparedness and Response in the Context of Sub-Saharan AfricaJOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 2 2000Donald A. Wilhite Although drought is a normal, recurring feature of climate, little progress has been made in drought management in most parts of the world. A United Nations study of selected Sub-Saharan African countries revealed that most states have little experience in proactive planning for drought. Only Botswana and South Africa have made serious efforts to develop drought preparedness and response. The lack of contingency planning for drought events in the region results from limited financial resources, inadequate understanding of drought impacts, and poor co-ordination among government agencies. A ten-step planning process, originally developed in 1991 for U.S. states, is suggested as an organizational tool for Sub-Saharan countries to use in the development of drought plans. The process, which emphasizes risk management rather than crisis management, is based on three primary components: (1) monitoring and early warning, (2) vulnerability and impact assessment, (3) mitigation and response. The steps in the process are generic; they can be adapted and applied to the various settings of Sub-Saharan Africa. [source] Early warning of agglomeration in fluidized beds by attractor comparisonAICHE JOURNAL, Issue 11 2000J. Ruud van Ommen An enhanced monitoring method, based on pressure fluctuation measurements, for observing nonstationarities in fluidized-bed hydrodynamics is presented. Experiments show that it can detect small changes in the particle-size distribution. Such a monitoring method is useful to give an early warning of the onset of agglomeration in a fluidized bed. In contrast to earlier methods, this method is insensitive to small changes in superficial gas velocity and can handle multiple signals, making it relevant to industrial application. By carefully choosing the measurement position, the method becomes also insensitive to small bed mass variations. It uses the attractor reconstructed from a measured pressure signal, which is a "fingerprint" of the hydrodynamics of the fluidized bed for a certain set of conditions. Using this method statistically the reconstructed attractor of a reference time series of pressure fluctuations (representing the desired fluidization behavior) is compared with that of successive time series measured during the bed operation. [source] The practice of early recognition and early intervention to prevent psychotic relapse in patients with schizophrenia: an exploratory study.JOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 3 2002Part In this article we describe the findings of an exploratory study into the application of early recognition and early intervention methods aimed at prevention of psychotic relapses in patients with schizophrenia. We addressed several models of symptom recognition plans and indicated how patients, healthcare professionals and other persons involved may be able to list and evaluate early warning signs systematically. We also paid attention to the role of the patient's family and to the potential effects of using early recognition and early intervention methods. In a follow-up article (part 2), we will focus more specifically on factors which favourably or adversely affect the use of early recognition and early intervention methods. The results of this exploratory study will be used to design an intervention protocol for nursing staff to serve as a tool for preparing symptoms recognition plans with the individual patient and his/her social network. [source] Information use and early warning effectiveness: Perspectives and prospectsJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 5 2009Chun Wei Choo This introductory article explores how the use of information affects the effectiveness of early warning systems. By effectiveness, we refer to the capacity of the system to detect and decide on the existence of a threat. There are two aspects to effectiveness: (a) being able to see the evidence that is indicative of a threat and (b) making the decision, based on the weight of the evidence, to warn that the threat exists. In early warning, information use is encumbered by cues that are fallible and equivocal. Cues that are true indicators of a threat are obscured in a cloud of events generated by chance. Moreover, policy makers face the difficult decision of whether to issue a warning based on the information received. Because the information is rarely complete or conclusive, such decisions have to consider the consequences of failing to warn or giving a false warning. We draw on sociocognitive theories of perception and judgment to analyze these two aspects of early warning: detection accuracy (How well does perception correspond to reality?) and decision sensitivity (How much evidence is needed to activate warning?) Using cognitive continuum theory, we examine how detection accuracy depends on the fit between the information needs profile of the threat and the information use environment of the warning system. Applying signal detection theory, we investigate how decision sensitivity depends on the assessment and balancing of the risks of misses and false alarms inherent in all early warning decision making. [source] Review of methods for measuring and comparing center performance after organ transplantationLIVER TRANSPLANTATION, Issue 10 2010James Neuberger The assessment of outcomes after transplantation is important for several reasons: it provides patients with data so that they can make informed decisions about the benefits of transplantation and the success of the transplant unit; it informs commissioners that resources are allocated properly; and it provides clinicians reassurance that results are acceptable or, if they are not, provides early warning so that problems can be identified, corrections can be instituted early, and all interested parties can be reassured that scarce resources are used fairly. The need for greater transparency in reporting outcomes after liver transplantation and for comparisons both between and within centers has led to a number of approaches being adopted for monitoring center performance. We review some of the commonly used methods, highlight their strengths and weaknesses, and concentrate on methods that incorporate risk adjustment. Measuring and comparing outcomes after transplantation is complex, and there is no single approach that gives a complete picture. All those using analyses of outcomes must understand the merits and limitations of individual methods. When used properly, such methods are invaluable in ensuring that a scarce resource is used effectively, any adverse trend in outcomes is identified promptly and remedied, and best performers are identified; they thus allow the sharing of best practices. However, when they are used inappropriately, such measurements may lead to inappropriate conclusions, encourage risk-averse behavior, and discourage innovation. Liver Transpl 16:1119,1128, 2010. © 2010 AASLD. [source] A method for selecting and monitoring medication sales for surveillance of gastroenteritis,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 10 2010Camille Pelat Abstract Purpose Monitoring appropriate categories of medication sales can provide early warning of certain disease outbreaks. This paper presents a methodology for choosing and monitoring medication sales relevant for the surveillance of gastroenteritis and assesses the operational characteristics of the selected medications for early warning. Methods Acute diarrhoea incidences in mainland France were obtained from the Sentinelles network surveillance system for the period 2000,2009. Medication sales grouped by therapeutic classes were obtained on the same period. Hierarchical clustering was used to select therapeutic classes correlating with disease incidence over the period. Alert thresholds were defined for the selected therapeutic classes. Single and multiple voter algorithms were investigated for outbreak detection based on sales crossing the thresholds. Sensitivity and specificity were calculated respective to known outbreaks periods. Results Four therapeutic classes were found to cluster with acute diarrhoea incidence. The therapeutic class other antiemetic and antinauseants had the best sensitivity (100%) and timeliness (1.625 weeks before official alerts), for a false alarm rate of 5%. Multiple voter algorithm was the most efficient with the rule: ,Emit an outbreak alert when at least three therapeutic classes are over their threshold' (sensitivity 100%, specificity 95%, timeliness 1.750 weeks before official alerts). Conclusions The presented method allowed selection of relevant therapeutic classes for surveillance of a specific condition. Multiple voter algorithm based on several therapeutic classes performed slightly better than the best therapeutic class alone, while improving robustness against abrupt changes occurring in a single therapeutic class. Copyright © 2010 John Wiley & Sons, Ltd. [source] Avoiding predators at night: antipredator strategies in red-tailed sportive lemurs (Lepilemur ruficaudatus)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2007Claudia Fichtel Abstract Although about one-third of all primate species are nocturnal, their antipredator behavior has rarely been studied directly. Crypsis and a solitary lifestyle have traditionally been considered to be the main adaptive antipredator strategies of nocturnal primates. However, a number of recent studies have revealed that nocturnal primates are not as cryptic and solitary as previously suggested. Thus, the antipredator strategies available for diurnal primates that rely on early detection and warning of approaching predators may also be available to nocturnal species. In order to shed additional light on the antipredator strategies of nocturnal primates, I studied pair-living red-tailed sportive lemurs (Lepilemur ruficaudatus) in Western Madagascar. In an experimental field study I exposed adult sportive lemurs that lived in pairs and had offspring to playbacks of vocalizations of their main aerial and terrestrial predators, as well as to their own mobbing calls (barks) given in response to disturbances at their tree holes. I documented the subjects' immediate behavioral responses, including alarm calls, during the first minute following a playback. The sportive lemurs did not give alarm calls in response to predator call playbacks or to playbacks with barks. Other behavioral responses, such as gaze and escape directions, corresponded to the hunting strategies of the two classes of predators, suggesting that the corresponding vocalizations were correctly categorized. In response to barks, they scanned the ground and fled. Because barks do not indicate any specific threats, they are presumably general alarm calls. Thus, sportive lemurs do not rely on early warning of acoustically simulated predators; rather, they show adaptive escape strategies and use general alarm calls that are primarily directed toward the predator but may also serve to warn kin and pair-partners. Am. J. Primatol. 69:611,624, 2007. © 2007 Wiley-Liss, Inc. [source] Post-summer heavy rainfall events in Southeast Brazil associated with South Atlantic Convergence ZoneATMOSPHERIC SCIENCE LETTERS, Issue 1 2010Kellen Carla Lima Abstract Heavy rainfall events (HREs) in the post-summer month of March in Southeast Brazil cause disasters such as floods, mudslides and landslides, mainly because the soil becomes saturated by February. Forty-five years of rainfall data show that heavy rainfall frequency increases again in the month of March. The composite anomaly fields of the atmospheric circulation during and before HREs associated with the formation of South Atlantic Convergence Zone show some special characteristics that may be used as a guide for early warning. The convergence of moisture flux in the troposphere over the region grows 40% during the 48 h before the HRE in March. Copyright © 2010 Royal Meteorological Society [source] The 2005 Wellington influenza outbreak: syndromic surveillance of Wellington Hospital Emergency Department activity may have provided early warningAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 3 2009Melissa McLeod Abstract Objectives: To assess whether the Wellington Emergency Department (ED) Respiratory Syndromic Surveillance System may have provided early warning of the influenza outbreak in Wellington schools during 2005, and as a result might have provided the opportunity for an earlier or more effective public health response. Methods: All events of respiratory syndrome, as defined by selected ICD 10 codes, were extracted from Wellington Hospital ED for the dates 1 January 2004 to 31 December 2006, and analysed using the Centers for Disease Control and Prevention (CDC) surveillance program, Early Aberration Reporting System (EARS). Daily events were analysed for total counts and by lifecycle age group. Seven day moving averages of the numbers of events were also calculated. Results: This study indicated that the surveillance system may have provided early warning of a potential respiratory outbreak. Regular exceedance flags were generated nine days prior to the initial notification received by Regional Public Health (RPH). The surveillance system also provided information on the type of illness (respiratory), the groups affected (5-14 year olds), and the progression of the outbreak (peak, end). Conclusions: The surveillance system might have worked by providing early notification of the outbreak. This may have prompted RPH to earlier investigate the potential outbreak and may have led to an earlier response. Implications: Surveillance of Emergency Department activity may be useful for early public health response. [source] Use of medium-range ensembles at the Met Office 2: Applications for medium-range forecastingMETEOROLOGICAL APPLICATIONS, Issue 3 2002M V Young The term ,medium range' is taken to refer to forecasts for lead times ranging from about 2 or 3 days ahead up to about 10 days ahead. A wide variety of numerical model products are available to the forecaster nowadays, and one of the most important of these is the ECMWF Ensemble Prediction System (EPS). This paper shows how forecasters at the Met Office use these products, in particular the EPS, in an operational environment in the production of medium-range forecasts for a variety of customers, and illustrates some of the techniques involved. Particular reference is made to the PREVIN post-processing system for the EPS which is described in the companion paper by Legg et al. (2002). Forecast products illustrated take the form of synoptic charts (produced primarily via Field Modification software), text guidance and other graphical formats. The probabilistic approach to forecasting is discussed with reference to various examples, in particular the application of the EPS in providing early warnings of severe weather for which risk assessment is increasingly important. A central theme of this paper is the vital role played by forecasters in interpreting the output from the models in terms of the likely weather elements, and using the EPS to help assess confidence levels for a particular forecast as well as possible alternative synoptic evolutions. Verification statistics are presented which demonstrate how the EPS helps the forecaster to add value to the wide range of individual deterministic model products and that furthermore, the forecaster can improve upon many probabilistic products derived directly from the ensemble. Copyright © 2002 Royal Meteorological Society. [source] Storm prediction over Europe using the ECMWF Ensemble Prediction SystemMETEOROLOGICAL APPLICATIONS, Issue 3 2002Roberto Buizza Three severe storms caused great damage in Europe in December 1999. The first storm hit Denmark and Germany on 3 and 4 December, and the other two storms crossed France and Germany on 26 and 28 December. In this study, the performance of the Ensemble Prediction System (EPS) at the European Centre for Medium-Range Weather Forecast (ECMWF) in predicting these intense storms is investigated. Results indicate that the EPS gave early indications of possible severe storm occurrence, and was especially useful when the deterministic TL319L60 forecasts issued on successive days were highly inconsistent. These results indicate that the EPS is a valuable tool for assessing quantitatively the risk of severe weather and issuing early warnings of possible disruptions. The impact of an increase of the ensemble system horizontal resolution (TL255 integration from a TL511 analysis instead of the operational TL159 integration from a TL319 analysis) on the system performance is also investigated. Results show that the resolution increase enhances the ensemble performance in predicting the position and the intensity of intense storms. Copyright © 2002 Royal Meteorological Society. [source] Side-effects of allergen-specific immunotherapy.CLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2006A prospective multi-centre study Summary Background and objective The safety of allergen-specific immunotherapy (SIT) is a parameter of great interest in the overall assessment of the treatment. A clinical database was developed in order to obtain early warnings of changes in the frequency and severity of side-effects and sufficient data for the evaluation of possible risk factors. Methods During a 3-year period, four allergy centres in Copenhagen, Denmark, included data from all patients initiating SIT to a common database. Information on initial allergic symptoms, allergens used for treatment, treatment regimens and systemic side-effects (SSEs) during the build-up phase was collected. Results A total of 1038 patients received treatment with 1709 allergens (timothy, birch, mugwort, house dust mite (HDM), cat, and wasp and bee venom), 23 047 injections in total. Most SIT patients completed the updosing phase without side-effects, but there was a significant difference between allergens: wasp (89%), birch (82%), HDM (81%), cat (74%) and grass (70%) (P=0.004). A total of 582 SSEs were registered in 341 patients. Most side-effects were mild grade 2 reactions (78%). A difference in severity between allergens was observed (P=0.02), with grass giving most problems. The type of allergen but not patient- or centre-related parameters seemed predictive of side-effects. Conclusions Allergen extracts differ in their tendency to produce side-effects. Multi-centre studies like the present one allow more patients to be evaluated, and thereby provide a more efficient surveillance of side-effects. Online Internet-based registration to a central national database of every allergen injection would be an even more powerful tool for evaluation of risk factors and surveillance of side-effects. [source] | ||||||||||||||||||||||