458 research outputs found

    Complex Unit Roots and Business Cycles: Are They Real?

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    In this paper the asymptotic properties of ARMA processes with complex- conjugate unit roots in the AR lag polynomial are studied. These processes behave quite differently from processes with a single root equal to 1. In particular, the asymptotic properties of a standardized version of the periodogram for such processes are analyzed, and a nonparametric test of the complex unit root hypothesis against the stationarity hypothesis is derived. This test is applied to the annual change of the monthly number of unemployed in the US, in order to see whether this time series has complex unit roots in the business cycle frequencies.

    A consistent conditional moment test of functional form

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    Conditional moment (CM) tests of functional form exploit the property that for correctly specified models the conditional expectation of certain functions of the observations should be almost surely equal to zero. A chi-square misspecification test can then be based on weighted means of thes

    Automated systems for the clinical laboratory: the user's needs

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    The Legitimacy, Accountability, and Ownership of an Impact-Based Forecasting Model in Disaster Governance

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    The global shift within disaster governance from disaster response to preparedness and risk reduction includes the emergency of novel Early Warning Systems such as impact based forecasting and forecast-based financing. In this new paradigm, funds usually reserved for response can be released before a disaster happens when an impact-based forecast—i.e., the expected humanitarian impact as a result of the forecasted weather—reaches a predefined danger level. The development of these impact-based forecasting models are promising, but they also come with significant implementation challenges. This article presents the data-driven impact-based forecasting model as developed by 510, an initiative of the Netherlands Red Cross. It elaborates on how questions on legitimacy, accountability and ownership influenced the implementation of the model within the Philippines with the Philippine Red Cross and the local government as the main stakeholders. The findings imply that the exchange of knowledge between the designer and manufacturer of impact-based models and the end users of those models fall short if novel Early Warnign Systems are seen as just a matter of technology transfer. Instead the development and implementation of impact based models should be based on mutual understanding of the users’ needs and the developers of such models

    Review of 14 drowning publications based on the Utstein style for drowning

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    Abstract Background The Utstein style for drowning (USFD) was published in 2003 with the aim of improving drowning research. To support a revision of the USFD, the current study aimed to generate an inventory of the use of the USFD parameters and compare the findings of the publications that have used the USFD. Methods A search in Pubmed, Embase, the Cochrane Library, Web of Science and Scopus was performed to identify studies that used the USFD and were published between 01-10-2003 and 22-03-2015. We also searched in Pubmed, Embase, the Cochrane Library, Web of Science, and Scopus for all publications that cited the two publications containing the original ILCOR advisory statement introducing and recommending the USFD. In total we identified 14 publications by groups that explicitly used elements of the USFD for collecting and reporting their data. Results Of the 22 core and 19 supplemental USFD parameters, 6–19 core (27–86%) and 1–12 (5–63%) supplemental parameters were used; two parameters (5%) have not been used in any publication. Associations with outcome were reported for nine core (41%) and five supplemental (26%) USFD parameters. The USFD publications also identified non-USFD parameters related to outcome: initial cardiac rhythm, time points and intervals during resuscitation, intubation at the drowning scene, first hospital core temperature, serum glucose and potassium, the use of inotropic/vasoactive agents and the Paediatric Index of Mortality 2-score. Conclusions Fourteen USFD based drowning publications have been identified. These publications provide valuable information about the process and quality of drowning resuscitation and confirm that the USFD is helpful for a structured comparison of the outcome of drowning resuscitation

    Resuscitation of Drowned Persons during the COVID-19 Pandemic: A Consensus Statement

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    Importance: Resuscitation is a niche example of how the COVID-19 pandemic has affected society in the long term. Those trained in cardiopulmonary resuscitation (CPR) face the dilemma that attempting to save a life may result in their own harm. This is most of all a problem for drowning, where hypoxia is the cause of cardiac arrest and ventilation is the essential first step in reversing the situation. Objective: To develop recommendations for water rescue organizations in providing their rescuers with safe drowning resuscitation procedures during the COVID-19 pandemic. Evidence Review: Two consecutive modified Delphi procedures involving 56 participants from 17 countries with expertise in drowning prevention research, resuscitation, and programming were performed from March 28, 2020, to March 29, 2021. In parallel, PubMed and Google Scholar were searched to identify new emerging evidence relevant to each core element, acknowledge previous studies relevant in the new context, and identify knowledge gaps. Findings: Seven core elements, each with their own specific recommendations, were identified in the initial consensus procedure and were grouped into 4 categories: (1) prevention and mitigation of the risks of becoming infected, (2) resuscitation of drowned persons during the COVID-19 pandemic, (3) organizational responsibilities, and (4) organizations unable to meet the recommended guidelines. The common measures of infection risk mitigation, personal protective equipment, and vaccination are the base of the recommendations. Measures to increase drowning prevention efforts reduce the root cause of the dilemma. Additional infection risk mitigation measures include screening all people entering aquatic facilities, defining criteria for futile resuscitation, and avoiding contact with drowned persons by rescuers with a high-risk profile. Ventilation techniques must balance required skill level, oxygen delivery, infection risk, and costs of equipment and training. Bag-mask ventilation with a high-efficiency particulate air filter by 2 trained rescuers is advised. Major implications for the methods, facilities, and environment of CPR training have been identified, including nonpractical skills to avoid being infected or to infect others. Most of all, the organization is responsible for informing their members about the impact of the COVID-19 pandemic and taking measures that maximize rescuer safety. Research is urgently needed to better understand, develop, and implement strategies to reduce infection transmission during drowning resuscitation. Conclusions and Relevance: This consensus document provides an overview of recommendations for water rescue organizations to improve the safety of their rescuers during the COVID-19 pandemic and balances the competing interests between a potentially lifesaving intervention and risk to the rescuer. The consensus-based recommendations can also serve as an example for other volunteer organizations and altruistic laypeople who may provide resuscitation.. © 2022 American Medical Association. All rights reserved

    Circumstances, outcome and quality of cardiopulmonary resuscitation by lifeboat crews

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    Background: Little is known regarding circumstances, outcomes and quality of cardiopulmonary resuscitation (CPR) and the use of automated external defibrillators (AEDs) performed by operational lifeboat crews. Our aim is to evaluate circumstances, outcomes and quality of CPR performed by the Royal Dutch Lifeboat Institution (KNRM) in out-of-hospital cardiac arrest (OHCA). Methods: The internal KNRM database has been used to identify and analyse all OHCA cases between July 2011 and December 2017. A limited set of AED data was available to study the quality of CPR. Results: In 37 patients the lifeboat crew members have performed CPR, of which 29 (78.4%) occurred under hostile conditions. The median response time to arrive at the location was 15 min. In 11 (29.7%) patients return of spontaneous circulation was achieved at any moment during CPR and 3 (8.1%) patients were still alive after one month. The lifeboat AED was used in 12 patients. Their recordings show a high median compression frequency (120, IQR 111–131) and prolonged median interruption periods (pre-analysis pause 11s (IQR 10–13), post-analysis pause 4s (IQR 3–8), pre-shock pause 24s (IQR 19–26), post-shock pause 6s (IQR 6–11), ventilation pause 6s (IQR 4–8) and other pauses 9s (IQR 4–17)). Conclusions: Compared to most out-of-hospital resuscitations, resuscitations by lifeboat crews have a low incidence, occur under difficult circumstances and in a younger population. AED's on lifeboats have not contributed to any of the survivals. Analysis of AED information can be used to study the quality of CPR and provide input for improving future training of lifeboat crews

    Determinants on lens spaces and cyclotomic units

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    The Laplacian functional determinants for conformal scalars and coexact one-forms are evaluated in closed form on inhomogeneous lens spaces of certain orders, including all odd primes when the essential part of the expression is given, formally as a cyclotomic unitComment: 18 pages, 1 figur
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