28 research outputs found
Modeling social resilience: Questions, answers, open problems
Resilience denotes the capacity of a system to withstand shocks and its
ability to recover from them. We develop a framework to quantify the resilience
of highly volatile, non-equilibrium social organizations, such as collectives
or collaborating teams. It consists of four steps: (i) \emph{delimitation},
i.e., narrowing down the target systems, (ii) \emph{conceptualization}, .e.,
identifying how to approach social organizations, (iii) formal
\emph{representation} using a combination of agent-based and network models,
(iv) \emph{operationalization}, i.e. specifying measures and demonstrating how
they enter the calculation of resilience. Our framework quantifies two
dimensions of resilience, the \emph{robustness} of social organizations and
their \emph{adaptivity}, and combines them in a novel resilience measure. It
allows monitoring resilience instantaneously using longitudinal data instead of
an ex-post evaluation
Resilience management processes in the offshore wind industry: Schematization and application to an export cable attack
Offshore wind energy (OWE) production is a crucial element for increasing the amount of renewable energy. Consequently, one can observe a strong and constant rise of the OWE industry, turning it to an important contributor of national energy provision. This trend, however, is accompanied by increasing pressure on the reliability, safety, and security of the OWE infrastructure. Related security threats are characterized by high uncertainty regarding impact and probability leading to considerable complication of the risk assessment. On the other hand, the resilience concept emphasizes the consideration of the system’s response to such threats, and thus, offers a solution for dealing with the high uncertainty. In this work, we present an approach for combining the strengths of risk and resilience management to provide a solution for handling security threats in OWE infrastructures. Within this context, we introduce a quality assessment enabling the quantification of the trustworthiness of obtained results
Management of anaphylaxis due to COVID-19 vaccines in the elderly
Older adults, especially men and/or those with diabetes, hypertension, and/or obesity, are prone to severe COVID-19. In some countries, older adults, particularly those residing in nursing homes, have been prioritized to receive COVID-19 vaccines due to high risk of death. In very rare instances, the COVID-19 vaccines can induce anaphylaxis, and the management of anaphylaxis in older people should be considered carefully. An ARIA-EAACI-EuGMS (Allergic Rhinitis and its Impact on Asthma, European Academy of Allergy and Clinical Immunology, and European Geriatric Medicine Society) Working Group has proposed some recommendations for older adults receiving the COVID-19 vaccines. Anaphylaxis to COVID-19 vaccines is extremely rare (from 1 per 100,000 to 5 per million injections). Symptoms are similar in younger and older adults but they tend to be more severe in the older patients. Adrenaline is the mainstay treatment and should be readily available. A flowchart is proposed to manage anaphylaxis in the older patients.Peer reviewe
Scaling rules for the analysis of blast loaded concrete structures - a critical literature review: Paper presented at 6th International Conference on Design and Analysis of Protective Structures, DAPS 2017, November 29 - December 1, 2017, Melbourne, Australia
A consistent set of scaling rules for concrete structures under blast loading is reviewed. The rules, analyzed with the Buckingham Π-Theorem, are in accordance with the cube root scaling rule [1].Assumptions made by their adaption in experiments are discussed by focusing on possible constraints. Furthermore, the rules are revalidated by experiments available in literature. Whereas blast waves scale well, many experiments denote a mismatch in the structural response. A material or structural dependent size effect is often stated to cause the mismatch, though in some cases, the performed experiment suffers from insufficient scaling. To quantify the effect of insufficient scaling, the experiments performed by Wang et al. [2], where blast loaded reinforced concrete slabs were tested at different scales, are modeled numerically. A finite element model, based on the RHT model and explicit consideration of reinforcement by beam elements, demonstrates that insufficient scaling can explain a major portion of the mismatch in the given case. It is concluded that, under certain limitations, scaled experiments are a powerful method to analyze blast loaded concrete structures when the related scaling rules are followed correctly
Blast-induced dynamic responses of reinforced concrete structures under progressive collapse
To study the response of reinforced concrete structures under progressive collapse induced by an actual blast event, an experimental programme on reinforced concrete frames subjected to contact detonation was conducted. The tested structure included a double-span beam with a middle joint, side columns and beam extensions connected to external restraints. The experimental programme employed similar geometry, reinforcing arrangement, material properties and boundary restraints from previous quasi-static as well as free-fall dynamic test series, which focused on the effects of horizontal restraint conditions on the mobilisation of catenary action. Compared to the corresponding static and free-fall tests conducted previously, the blast-induced tests simulated the condition of a progressive collapse event triggered by an explosive charge which is close to actual accidental/terrorist situations. As a result, initial effects/damages created by the initial blast effects-that is uplift of the double-span beam and blast pressure on beam and column-were witnessed and well captured. Damage patterns and failure modes from the blast tests were compared with those from related quasi-static and free-fall tests to emphasise the actual behaviour of structures under realistic explosive attacks. Finally, the blast tests also indicated the limitations of some simplified dynamic assessment methods when applying the single column removal assumption.Ministry of Home AffairsThis research is funded by the research grant GPC: MHA 191/9/1/345 provided by the Ministry of Home Affairs, Singapore and by the Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 107.01-2018.01. The authors greatly appreciate this financial support
Aktuelle Forschungsergebnisse zum baulichen Schutz für Großbauwerke und Risikomanagement für kritische Infrastrukturen und städtische Bereiche
Exercise right heart catheterization before and after balloon pulmonary angioplasty in inoperable patients with chronic thromboembolic pulmonary hypertension
Background: Balloon pulmonary angioplasty is an evolving, interventional treatment option for inoperable patients with chronic thromboembolic pulmonary hypertension (CTEPH). Pulmonary hypertension at rest as well as exercise capacity is considered to be relevant outcome parameters. The aim of the present study was to determine whether measurement of pulmonary hemodynamics during exercise before and six months after balloon pulmonary angioplasty have an added value.
Methods: From March 2014 to July 2018, 172 consecutive patients underwent balloon pulmonary angioplasty. Of these, 64 consecutive patients with inoperable CTEPH underwent a comprehensive diagnostic workup that included right heart catheterization at rest and during exercise before balloon pulmonary angioplasty treatments and six months after the last intervention.
Results: Improvements in pulmonary hemodynamics at rest and during exercise, in quality of life, and in exercise capacity were observed six months after balloon pulmonary angioplasty: WHO functional class improved in 78% of patients. The mean pulmonary arterial pressure (mPAP) at rest was reduced from 41 ± 9 to 31 ± 9 mmHg (p < 0.0001). The mPAP/cardiac output slope decreased after balloon pulmonary angioplasty (11.2 ± 25.6 WU to 7.7 ± 4.1 WU; p < 0.0001), and correlated with N-terminal fragment of pro-brain natriuretic peptide (p = 0.035) and 6-minute walking distance (p = 0.01).
Conclusions: Exercise right heart catheterization provides valuable information on the changes of pulmonary hemodynamics after balloon pulmonary angioplasty in inoperable CTEPH patients that are not obtainable by measuring resting hemodynamics
Dynamics of high-sensitivity cardiac troponin T during therapy with balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension
Aims: Balloon pulmonary angioplasty (BPA) is an interventional treatment modality for inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Therapy monitoring, based on non-invasive biomarkers, is a clinical challenge. This post-hoc study aimed to assess dynamics of high-sensitivity cardiac troponin T (hs-cTnT) as a marker for myocardial damage and its relation to N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels as a marker for cardiac wall stress.
Methods and results: This study included 51 consecutive patients who underwent BPA treatment and completed a 6-month follow-up (6-MFU) between 3/2014 and 3/2017. Biomarker measurement was performed consecutively prior to each BPA and at 6-MFU.
In total, the 51 patients underwent an average of 5 BPA procedures. The 6-month survival rate was 96.1%. The baseline (BL) meanPAP (39.5±12.1mmHg) and PVR (515.8±219.2dyn×sec×cm-5) decreased significantly within the 6-MFU (meanPAP: 32.6±12.6mmHg, P<0.001; PVR: 396.9±182.6dyn×sec×cm-5, P<0.001). At BL, the median hs-cTnT level was 11 (IQR 6–16) ng/L and the median NT-proBNP level was 820 (IQR 153–1872) ng/L. The levels of both biomarkers decreased steadily after every BPA, showing the first significant difference after the first procedure. Within the 6-MFU, hs-cTnT levels (7 [IQR 5–12] ng/L; P<0.001) and NT-proBNP levels (159 [IQR 84–464] ng/l; P<0.001) continued to decrease. The hs-cTnT levels correlated with the PVR (rrs = 0.42; p = 0.005), the meanPAP (rrs = 0.32; p = 0.029) and the NT-proBNP (rrs = 0.51; p<0.001) levels at BL.
Conclusion: Non-invasive biomarker measurement provides valuable evidence for the decreasing impairment of myocardial function and structure during BPA therapy. Changes in hs-cTNT levels are suggestive for a reduction in ongoing myocardial damage
Dynamics of high-sensitivity cardiac troponin T during therapy with balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension.
AIMS:Balloon pulmonary angioplasty (BPA) is an interventional treatment modality for inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Therapy monitoring, based on non-invasive biomarkers, is a clinical challenge. This post-hoc study aimed to assess dynamics of high-sensitivity cardiac troponin T (hs-cTnT) as a marker for myocardial damage and its relation to N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels as a marker for cardiac wall stress. METHODS AND RESULTS:This study included 51 consecutive patients who underwent BPA treatment and completed a 6-month follow-up (6-MFU) between 3/2014 and 3/2017. Biomarker measurement was performed consecutively prior to each BPA and at 6-MFU. In total, the 51 patients underwent an average of 5 BPA procedures. The 6-month survival rate was 96.1%. The baseline (BL) meanPAP (39.5±12.1mmHg) and PVR (515.8±219.2dyn×sec×cm-5) decreased significantly within the 6-MFU (meanPAP: 32.6±12.6mmHg, P<0.001; PVR: 396.9±182.6dyn×sec×cm-5, P<0.001). At BL, the median hs-cTnT level was 11 (IQR 6-16) ng/L and the median NT-proBNP level was 820 (IQR 153-1872) ng/L. The levels of both biomarkers decreased steadily after every BPA, showing the first significant difference after the first procedure. Within the 6-MFU, hs-cTnT levels (7 [IQR 5-12] ng/L; P<0.001) and NT-proBNP levels (159 [IQR 84-464] ng/l; P<0.001) continued to decrease. The hs-cTnT levels correlated with the PVR (rrs = 0.42; p = 0.005), the meanPAP (rrs = 0.32; p = 0.029) and the NT-proBNP (rrs = 0.51; p<0.001) levels at BL. CONCLUSION:Non-invasive biomarker measurement provides valuable evidence for the decreasing impairment of myocardial function and structure during BPA therapy. Changes in hs-cTNT levels are suggestive for a reduction in ongoing myocardial damage