121 research outputs found
Agent-based simulation of a financial market
This paper introduces an agent-based artificial financial market in which
heterogeneous agents trade one single asset through a realistic trading
mechanism for price formation. Agents are initially endowed with a finite
amount of cash and a given finite portfolio of assets. There is no
money-creation process; the total available cash is conserved in time. In each
period, agents make random buy and sell decisions that are constrained by
available resources, subject to clustering, and dependent on the volatility of
previous periods. The model herein proposed is able to reproduce the
leptokurtic shape of the probability density of log price returns and the
clustering of volatility. Implemented using extreme programming and
object-oriented technology, the simulator is a flexible computational
experimental facility that can find applications in both academic and
industrial research projects.Comment: 11 pages, 3 EPS figures, LaTEX. To be published in Physica A
(Proceedings of the NATO Advanced Research Workshop on Application of Physics
in Economic Modelling, Prague 8-10 February 2001
Depression or anxiety in adult twins is associated with asthma diagnosis but not with offspring asthma
Background: Asthma is common in both children and adults in the Western world, just like anxiety and depression. While some research has revealed that these diseases might share important environmental and pathophysiological aspects, the exact mechanisms still remain unclear.
Objective: To study the correlation firstly between depression or anxiety and asthma diagnosis in adult twins, and secondly the association between parental depression or anxiety and offspring asthma in children of twins.
Methods: In total, 24,685 adult twins aged 20-47 years were interviewed or completed a web-based questionnaire and their children were identified through the Multi-Generation Register. Asthma diagnosis was obtained from the Patient Register and the Prescribed Drug Register. Assessment of depression and anxiety was obtained from questionnaires using Center for Epidemiologic Studies Depression Scale (CES-D), Major Depression and Generalized Anxiety Disorder (GAD) from DSM-IV. The association between depression or anxiety and asthma was analyzed with logistic regression adjusting for confounders in twins and offspring. To address genetic and familial environmental confounding we performed a co-twin analysis using disease-discordant twin pairs.
Results: We found an association between asthma and CES-D, major depression and GAD, e.g. adjusted OR for major depression and register-based asthma 1.56(1.36-1.79). Most of the point estimates remained in the co-twin control analysis, indicating that the association was likely not due to genetic or familial environmental factors. There was no association between parental depression and/or anxiety and asthma diagnosis in the offspring which implies lack of genetic confounding.
Conclusions: We found an association between own asthma diagnosis and anxiety or depression, but not with offspring asthma. Our results indicate that the associations were not due to confounding from genes or environment shared by the twins.NoneManuscrip
Time projection chambers for the T2K near detectors
The T2K experiment is designed to study neutrino oscillation properties by directing a high intensity neutrino beam produced at J-PARC in Tokai, Japan, towards the large Super-Kamiokande detector located 295 km away, in Kamioka, Japan. The experiment includes a sophisticated near detector complex, 280 m downstream of the neutrino production target in order to measure the properties of the neutrino beam and to better understand neutrino interactions at the energy scale below a few GeV. A key element of the near detectors is the ND280 tracker, consisting of two active scintillator-bar target systems surrounded by three large time projection chambers (TPCs) for charged particle tracking. The data collected with the tracker is used to study charged current neutrino interaction rates and kinematics prior to oscillation, in order to reduce uncertainties in the oscillation measurements by the far detector. The tracker is surrounded by the former UA1/Nomad dipole magnet and the TPCs measure the charges, momenta, and particle types of charged particles passing through them. Novel features of the TPC design include its rectangular box layout constructed from composite panels, the use of bulk micromegas detectors for gas amplification, electronics readout based on a new ASIC, and a photoelectron calibration system. This paper describes the design and construction of the TPCs, the micromegas modules, the readout electronics, the gas handling system, and shows the performance of the TPCs as deduced from measurements with particle beams, cosmic rays, and the calibration system
Age-Related Effects of COVID-19 Pandemic on Mechanical Reperfusion and 30-Day Mortality for STEMI: Results of the ISACS-STEMI COVID-19 Registry
Background: The constraints in the management of patients with ST-segment elevation myocardial infarction (STEMI) during the COVID-19 pandemic have been suggested to have severely impacted mortality levels. The aim of the current analysis is to evaluate the age-related effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI within the registry ISACS-STEMI COVID-19. Methods: This retrospective multicenter registry was performed in high-volume PPCI centers on four continents and included STEMI patients undergoing PPCI in March-June 2019 and 2020. Patients were divided according to age (= 75 years). The main outcomes were the incidence and timing of PPCI, (ischemia time longer than 12 h and door-to-balloon longer than 30 min), and in-hospital or 30-day mortality. Results: We included 16,683 patients undergoing PPCI in 109 centers. In 2020, during the pandemic, there was a significant reduction in PPCI as compared to 2019 (IRR 0.843 (95%-CI: 0.825-0.861, p < 0.0001). We found a significant age-related reduction (7%, p = 0.015), with a larger effect on elderly than on younger patients. Furthermore, we observed significantly higher 30-day mortality during the pandemic period, especially among the elderly (13.6% vs. 17.9%, adjusted HR (95% CI) = 1.55 [1.24-1.93], p < 0.001) as compared to younger patients (4.8% vs. 5.7%; adjusted HR (95% CI) = 1.25 [1.05-1.49], p = 0.013), as a potential consequence of the significantly longer ischemia time observed during the pandemic. Conclusions: The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures, with a larger reduction and a longer delay to treatment among elderly patients, which may have contributed to increase in-hospital and 30-day mortality during the pandemic
Age-Related Effects of COVID-19 Pandemic on Mechanical Reperfusion and 30-Day Mortality for STEMI : Results of the ISACS-STEMI COVID-19 Registry
Background: The constraints in the management of patients with ST-segment elevation
myocardial infarction (STEMI) during the COVID-19 pandemic have been suggested to have severely
impacted mortality levels. The aim of the current analysis is to evaluate the age-related effects of
the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI within the
registry ISACS-STEMI COVID-19. Methods: This retrospective multicenter registry was performed
in high-volume PPCI centers on four continents and included STEMI patients undergoing PPCI
in March–June 2019 and 2020. Patients were divided according to age (< or ≥75 years). The main
outcomes were the incidence and timing of PPCI, (ischemia time longer than 12 h and door-to-balloon
longer than 30 min), and in-hospital or 30-day mortality. Results: We included 16,683 patients
undergoing PPCI in 109 centers. In 2020, during the pandemic, there was a significant reduction in
PPCI as compared to 2019 (IRR 0.843 (95%-CI: 0.825–0.861, p < 0.0001). We found a significant agerelated reduction (7%, p = 0.015), with a larger effect on elderly than on younger patients. Furthermore,
we observed significantly higher 30-day mortality during the pandemic period, especially among the
elderly (13.6% vs. 17.9%, adjusted HR (95% CI) = 1.55 [1.24–1.93], p < 0.001) as compared to younger
patients (4.8% vs. 5.7%; adjusted HR (95% CI) = 1.25 [1.05–1.49], p = 0.013), as a potential consequence
of the significantly longer ischemia time observed during the pandemic. Conclusions: The COVID-19
pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in
PPCI procedures, with a larger reduction and a longer delay to treatment among elderly patients,
which may have contributed to increase in-hospital and 30-day mortality during the pandemic
Impact of Smoking Status on Mortality in STEMI Patients Undergoing Mechanical Reperfusion for STEMI : Insights from the ISACS–STEMI COVID-19 Registry
The so-called “smoking paradox”, conditioning lower mortality in smokers among STEMI
patients, has seldom been addressed in the settings of modern primary PCI protocols. The ISACS–
STEMI COVID-19 is a large-scale retrospective multicenter registry addressing in-hospital mortality,
reperfusion, and 30-day mortality among primary PCI patients in the era of the COVID-19 pandemic.
Among the 16,083 STEMI patients, 6819 (42.3%) patients were active smokers, 2099 (13.1%) previous smokers, and 7165 (44.6%) non-smokers. Despite the impaired preprocedural recanalization
(p < 0.001), active smokers had a significantly better postprocedural TIMI flow compared with nonsmokers (p < 0.001); this was confirmed after adjustment for all baseline and procedural confounders,
and the propensity score. Active smokers had a significantly lower in-hospital (p < 0.001) and 30-day
(p < 0.001) mortality compared with non-smokers and previous smokers; this was confirmed after
adjustment for all baseline and procedural confounders, and the propensity score. In conclusion, in
our population, active smoking was significantly associated with improved epicardial recanalization
and lower in-hospital and 30-day mortality compared with previous and non-smoking histor
Results of the ISACS-STEMI COVID-19 Registry
Publisher Copyright: © 2023 by the authors.Background. Several reports have demonstrated the impact of the COVID-19 pandemic on the management and outcome of patients with ST-segment elevation myocardial infarction (STEMI). The aim of the current analysis is to investigate the potential gender difference in the effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI patients within the ISACS-STEMI COVID-19 Registry. Methods. This retrospective multicenter registry was performed in high-volume primary percutaneous coronary intervention (PPCI) centers on four continents and included STEMI patients undergoing PPCIs in March–June 2019 and 2020. Patients were divided according to gender. The main outcomes were the incidence and timing of the PPCI, (ischemia time ≥ 12 h and door-to-balloon ≥ 30 min) and in-hospital or 30-day mortality. Results. We included 16683 STEMI patients undergoing PPCIs in 109 centers. In 2020 during the pandemic, there was a significant reduction in PPCIs compared to 2019 (IRR 0.843 (95% CI: 0.825–0.861, p < 0.0001). We did not find a significant gender difference in the effects of the COVID-19 pandemic on the numbers of STEMI patients, which were similarly reduced from 2019 to 2020 in both groups, or in the mortality rates. Compared to prepandemia, 30-day mortality was significantly higher during the pandemic period among female (12.1% vs. 8.7%; adjusted HR [95% CI] = 1.66 [1.31–2.11], p < 0.001) but not male patients (5.8% vs. 6.7%; adjusted HR [95% CI] = 1.14 [0.96–1.34], p = 0.12). Conclusions. The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures similarly observed in both genders. Furthermore, we observed significantly increased in-hospital and 30-day mortality rates during the pandemic only among females. Trial registration number: NCT 04412655.publishersversionpublishe
Impact of chronic obstructive pulmonary disease on short-term outcome in patients with ST-elevation myocardial infarction during COVID-19 pandemic: insights from the international multicenter ISACS-STEMI registry
Background Chronic obstructive pulmonary disease (COPD) is projected to become the third cause of mortality worldwide. COPD shares several pathophysiological mechanisms with cardiovascular disease, especially atherosclerosis. However, no definite answers are available on the prognostic role of COPD in the setting of ST elevation myocardial infarction (STEMI), especially during COVID-19 pandemic, among patients undergoing primary angioplasty, that is therefore the aim of the current study. Methods In the ISACS-STEMI COVID-19 registry we included retrospectively patients with STEMI treated with primary percutaneous coronary intervention (PCI) between March and June of 2019 and 2020 from 109 high-volume primary PCI centers in 4 continents. Results A total of 15,686 patients were included in this analysis. Of them, 810 (5.2%) subjects had a COPD diagnosis. They were more often elderly and with a more pronounced cardiovascular risk profile. No preminent procedural dissimilarities were noticed except for a lower proportion of dual antiplatelet therapy at discharge among COPD patients (98.9% vs. 98.1%, P = 0.038). With regards to short-term fatal outcomes, both in-hospital and 30-days mortality occurred more frequently among COPD patients, similarly in pre-COVID-19 and COVID-19 era. However, after adjustment for main baseline differences, COPD did not result as independent predictor for in-hospital death (adjusted OR [95% CI] = 0.913[0.658-1.266], P = 0.585) nor for 30-days mortality (adjusted OR [95% CI] = 0.850 [0.620-1.164], P = 0.310). No significant differences were detected in terms of SARS-CoV-2 positivity between the two groups. Conclusion This is one of the largest studies investigating characteristics and outcome of COPD patients with STEMI undergoing primary angioplasty, especially during COVID pandemic. COPD was associated with significantly higher rates of in-hospital and 30-days mortality. However, this association disappeared after adjustment for baseline characteristics. Furthermore, COPD did not significantly affect SARS-CoV-2 positivity. Trial registration number: NCT 04412655 (2nd June 2020)
Gender Difference in the Effects of COVID-19 Pandemic on Mechanical Reperfusion and 30-Day Mortality for STEMI: Results of the ISACS-STEMI COVID-19 Registry
Background. Several reports have demonstrated the impact of the COVID-19 pandemic on
the management and outcome of patients with ST-segment elevation myocardial infarction (STEMI).
The aim of the current analysis is to investigate the potential gender difference in the effects of the
COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI patients within the
ISACS-STEMI COVID-19 Registry. Methods. This retrospective multicenter registry was performed
in high-volume primary percutaneous coronary intervention (PPCI) centers on four continents and
included STEMI patients undergoing PPCIs in March–June 2019 and 2020. Patients were divided
according to gender. The main outcomes were the incidence and timing of the PPCI, (ischemia time
≥ 12 h and door-to-balloon ≥ 30 min) and in-hospital or 30-day mortality. Results. We included
16683 STEMI patients undergoing PPCIs in 109 centers. In 2020 during the pandemic, there was a
significant reduction in PPCIs compared to 2019 (IRR 0.843 (95% CI: 0.825–0.861, p < 0.0001). We did
not find a significant gender difference in the effects of the COVID-19 pandemic on the numbers of
STEMI patients, which were similarly reduced from 2019 to 2020 in both groups, or in the mortality
rates. Compared to prepandemia, 30-day mortality was significantly higher during the pandemic
period among female (12.1% vs. 8.7%; adjusted HR [95% CI] = 1.66 [1.31–2.11], p < 0.001) but not
male patients (5.8% vs. 6.7%; adjusted HR [95% CI] = 1.14 [0.96–1.34], p = 0.12). Conclusions. The
COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a
16% reduction in PPCI procedures similarly observed in both genders. Furthermore, we observed
significantly increased in-hospital and 30-day mortality rates during the pandemic only among
females. Trial registration number: NCT 04412655
- …