44 research outputs found

    Postfire hydrologic response along the Central California (USA) coast: insights for the emergency assessment of postfire debris-flow hazards

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    The steep, tectonically active terrain along the Central California (USA) coast is well known to produce deadly and destructive debris flows. However, the extent to which fire affects debris-flow susceptibility in this region is an open question. We documented the occurrence of postfire debris floods and flows following the landfall of a storm that delivered intense rainfall across multiple burn areas. We used this inventory to evaluate the predictive performance of the US Geological Survey M1 likelihood model, a tool that presently underlies the emergency assessment of postfire debris-flow hazards in the western USA. To test model performance, we used the threat score skill statistic and found that the rainfall thresholds estimated by the M1 model for the Central California coast performed similarly to training (Southern California) and testing (Intermountain West) data associated with the original model calibration. Model performance decreased when differentiating between “minor” and “major” postfire hydrologic response types, which weigh effects on human life and infrastructure. Our results underscore that the problem of false positives is a major challenge for developing accurate rainfall thresholds for the occurrence of postfire debris flows. As wildfire activity increases throughout the western USA, so too will the demand for the assessment of postfire debris-flow hazards. We conclude that additional collection of field-verified inventories of postfire hydrologic response will be critical to prioritize which model variables may be suitable candidates for regional calibration or replacement

    Landslides Triggered by the MW 7.8 14 November 2016 Kaikoura Earthquake, New Zealand

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    The MW 7.8 14 November 2016 Kaikoura earthquake generated more than 10000 landslides over a total area of about 10000 km2, with the majority concentrated in a smaller area of about 3600 km2. The largest landslide triggered by the earthquake had an approximate volume of 20 (±2) M m3, with a runout distance of about 2.7 km, forming a dam on the Hapuku River. In this paper, we present version 1.0 of the landslide inventory we have created for this event. We use the inventory presented in this paper to identify and discuss some of the controls on the spatial distribution of landslides triggered by the Kaikoura earthquake. Our main findings are (1) the number of medium to large landslides (source area ≄10000 m2) triggered by the Kaikoura earthquake is smaller than for similar sized landslides triggered by similar magnitude earthquakes in New Zealand; (2) seven of the largest eight landslides (from 5 to 20 x 106 m3) occurred on faults that ruptured to the surface during the earthquake; (3) the average landslide density within 200 m of a mapped surface fault rupture is three times that at a distance of 2500 m or more from a mapped surface fault rupture ; (4) the “distance to fault” predictor variable, when used as a proxy for ground-motion intensity, and when combined with slope angle, geology and elevation variables, has more power in predicting landslide probability than the modelled peak ground acceleration or peak ground velocity; and (5) for the same slope angles, the coastal slopes have landslide point densities that are an order of magnitude greater than those in similar materials on the inland slopes, but their source areas are significantly smaller

    Comparison of outcome and characteristics between 6343 COVID-19 patients and 2256 other community-acquired viral pneumonia patients admitted to Dutch ICUs

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    Purpose: Describe the differences in characteristics and outcomes between COVID-19 and other viral pneumonia patients admitted to Dutch ICUs. Materials and methods: Data from the National-Intensive-Care-Evaluation-registry of COVID-19 patients admitted between February 15th and January 1th 2021 and other viral pneumonia patients admitted between January 1st 2017 and January 1st 2020 were used. Patients' characteristics, the unadjusted, and adjusted in-hospital mortality were compared. Results: 6343 COVID-19 and 2256 other viral pneumonia patients from 79 ICUs were included. The COVID-19 patients included more male (71.3 vs 49.8%), had a higher Body-Mass-Index (28.1 vs 25.5), less comorbidities (42.2 vs 72.7%), and a prolonged hospital length of stay (19 vs 9 days). The COVID-19 patients had a significantly higher crude in-hospital mortality rate (Odds ratio (OR) = 1.80), after adjustment for patient characteristics and ICU occupancy rate the OR was respectively 3.62 and 3.58. Conclusion: Higher mortality among COVID-19 patients could not be explained by patient characteristics and higher ICU occupancy rates, indicating that COVID-19 is more severe compared to other viral pneumonia. Our findings confirm earlier warnings of a high need of ICU capacity and high mortality rates among relatively healthy COVID-19 patients as this may lead to a higher mental workload for the staff. (c) 2021 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/)

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Multifunctionele Waterkeringen: Onderzoek naar de mogelijkheden voor flexibel gebruik van de waterkering

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    Het Corporate Innovatieprogramma van Rijkswaterstaat levert een bijdrage aan de waterveiligheid van Nederland. Waterveiligheid is een continue opgave waaraan Nederland werkt. Rijkswaterstaat en de waterschappen zijn de hoofdrolspelers in het uitvoeren van maatregelen voor hoogwaterbescherming en waterveiligheid. Daarbij lopen zij soms tegen de grenzen aan van een effectieve, doelmatige aanpak. Nederland is dichtbevolkt en dichtbebouwd waardoor de samenleving steeds vaker te maken krijgt met de ingrepen voor de waterveiligheid. De kosten om maatregelen uit te voeren nemen toe, tegelijkertijd staan beschikbare middelen om te investeren onder druk. Vernieuwingen in de aanpak van maatregelen voor hoogwaterbescherming zijn nodig. Om te kunnen anticiperen op de effectieve en doelmatige uitvoering van maatregelen voor hoogwaterbescherming, in samenhang met andere ruimtelijke opgaven en ontwikkelingen, is meer kennis nodig of we alle instrumenten voor handen hebben dan wel benutten. Een van de aandachtsgebieden hierin betreft de verbetering/versterking van waterkeringen, vooral dijken, in samenhang met andere gebiedsopgaven. We nemen waar dat de huidige aanpak van dijkversterkingen volstaat, maar tegelijkertijd relatief sectoraal is. Kansen om meer te doen met andere ruimtelijke opgaven worden maar moeizaam benut. Integraliteit in dijkversterking blijkt een lastige opgave doordat processen niet eenvoudig zijn te combineren en besluitvorming in de publieke (nationaal versus lokaal) en publieke-private omgeving opgehangen lijkt aan te sturende (juridische) kaders, complexe organisatievormen (programma's, projecten) en een risicomijdende houding. De behoefte bestaat aan meer inzicht in mogelijkheden van een integrale en flexibele aanpak van dijkversterking in zowel tijd als ruimte. Dit rapport presenteert uitkomsten van een verkenning waarbij het werken aan waterkeringen vanuit een breder perspectief wordt aangevlogen. Er wordt een aanpak voorgesteld om koppelkansen te creeren in het gebied rondom de waterkering door de perspectieven tijd en ruimte nadrukkelijk mee te nemen. Urgentie van de waterveiligheidsopgave is daarbij beklemmend in de zoektocht naar synergie. Bij sprake van grote urgentie rondom waterveiligheid is er weinig ruimte en flexibiliteit om te zoeken naar meekoppelkansen. De tijdschalen waarop ontwikkelingen plaatsvinden lopen niet synchroon waardoor integratie tot complexe uitdagingen kan leiden of onmogelijk wordt. De factor 'ruimte' wordt bepalend als de opgaven niet gelijktijdig plaatsvinden. Ruimte is de onderlegger voor alle partijen, dus samenwerking is vereist.Deltaprogramm
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