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Prognostic impact of late gadolinium enhancement at the right ventricular insertion points in non-ischemic dilated cardiomyopathy.
No full textAimsTo evaluate the baseline characteristics and the prognostic implications associated with late gadolinium enhancement limited to the right ventricular insertion points (IP-LGE) or present at both the right ventricular insertion points and the left ventricle (IP&LV-LGE) in non-ischemic dilated cardiomyopathy (DCM). Methods and results Retrospective observational multicenter cohort study including 1165 consecutive patients with DCM evaluated by cardiac magnetic resonance. The primary endpoint included appropriate defibrillator therapies, sustained ventricular tachycardia, resuscitated cardiac arrest or sudden death. The secondary outcome encompassed heart failure hospitalizations, heart transplant, left ventricular assist device implantation and end-stage heart failure death. IP-LGE was found in 72 patients (6%), who had clinical characteristics closer to LGE- than to LGE+ patients. During follow-up (median 36 months), none of the IP-LGE patients experienced the primary endpoint. The cumulative incidence of the primary endpoint was similar between IP-LGE and LGE- patients (p=1) while IP-LGE had significantly lower cumulative incidence as compared to LGE+ patients (p<0.001). As compared to IP-LGE patients, the cumulative incidence of the secondary endpoint was similar in LGE- cases (p=0.86) but tended to be higher in LGE+ patients (p=0.06). Both clinical characteristics and outcomes were similar between IP&LV-LGE patients and the rest of LGE+ cases. ConclusionsIn a large cohort of DCM patients, IP-LGE was associated with similar outcome as compared to LGE- patients and with significant lower risk of ventricular arrhythmias and sudden death as compared to LGE+ cases. Patients with IP&LV-LGE had clinical characteristics and outcomes similar to the rest of LGE+ cases
Save money to lose money? Implications of opting out of a voluntary audit review for a firm’s cost of debt
No full textAn audit review (AR) is a mechanism used by boards to assess the quality of interim financial reports on a timely basis. In Canada, the AR is voluntary, with listed firms mandated to disclose when they choose not to purchase additional audit verification. Given the relatively low cost of an AR, opting out of it can be regarded as a negative signal, especially in the context of lenders’ sensitivity to downside risk. Using a sample of 7,585 firm-year observations from 1,616 public firms in Canada over the period 2004-2015, we document that firms without a voluntary AR have a higher cost of debt than firms with an AR. Furthermore, after firms opt out of the AR, the increase in the cost of debt is accompanied by a rise in discretionary abnormal accruals and managers’ stock-based compensation. Moreover, no-AR firms are more likely to reduce post-switch private borrowing and have lower equity analyst following. Our study is the first to document that although listed borrowers that opt out of an AR have a higher cost of debt financing, they are concurrently able to engage in more earnings management and grant their managers higher stock-based compensation because of lower external monitoring
THE APPLICATION OF THE ARBITRARY-ORDER GALERKIN REDUCTION METHOD TO THE DYNAMIC ANALYSIS OF A ROTOR WITH A PRELOADED SINGLE-PAD FOIL-AIR BEARING
No full textModelling and controller design for a five-link inverted pendulum
No full textThe inverted pendulum is a fast-moving, highly nonlinear and unstable system with multiple variables and nonminimum phase that requires effective stabilization controllers. Therefore, studies into inverted pendulum systems theoretically and practically have great significance. The Euler-Lagrange Equation is used to calculate the mathematical model for a five-link inverted pendulum system. Linear Quadratic Gaussian (LQG) and H∞ are implemented using the developed model, with the Kalman Filter serving as the observer. The closed-loop system are simulated by the Matlab-Simscape platform and the controller are evaluated in relation to the system performance
Nanoparticle transport within non-Newtonian fluid flow in porous media
No full textControl over dispersion of nanoparticles in polymer solutions through porous media is important for subsurface applications such as soil remediation and enhanced oil recovery. Dispersion is affected by the spatial heterogeneity of porous media, the non-Newtonian behavior of polymer solutions, and the Brownian motion of nanoparticles. Here, we use the Euler-Lagrangian method to simulate the flow of nanoparticles and inelastic non-Newtonian fluids (described by Meter model) in a range of porous media samples and injection rates. In one case, we use a fine mesh of more than 3 million mesh points to model nanoparticles transport in a sandstone sample. The results show that the velocity distribution of nanoparticles in the porous medium is non-Gaussian, which leads to the non-Fickian behaviour of nanoparticles dispersion. Due to pore space confinement, the longtime mean square displacement of nanoparticles depends nonlinearly on time. Additionally the gradient of shear stress in the pore-space of the porous medium dictates the transport behaviour of nanoparticles in the porous medium. Furthermore, the Brownian motion of nanoparticles increases the dispersion of nanoparticles along the longitudinal and transverse direction
Statistical Disclosure Control and Developments in Formal Privacy: In Memoriam to Chris Skinner
No full textI provide an overview of the evolution of Statistical Disclosure Control (SDC) research over the last decades and how it has evolved to handle the data revolution with more formal definitions of privacy. I emphasize the many contributions by Chris Skinner in the research areas of SDC. I review his seminal research, starting in the 1990’s with his work on the release of UK Census sample microdata. This led to a wide-range of research on measuring the risk of re-identification in survey microdata through probabilistic models. I also focus on other aspects of Chris’ research in SDC. Chris was the recipient of the 2019 Waksberg Award and sadly never got a chance to present his Waksberg Lecture at the Statistics Canada International Methodology Symposium. This paper follows the outline that Chris had prepared in preparation for that lecture
Control flow graph, formal verification and constraint programming techniques
No full textFormal program verification is a generally undecidable problem. Bounded Model Checking (BMC) is one method that can achieve decidability by searching for violations of properties of a program up to a bound k. BMC reduces the program verification problem to the classic NP-complete Boolean Satisfiability (SAT). However, it can still lead to an exponential state-space exploration due to the program’s large and possibly unbounded loops. In this case, there might be many execution paths to traverse through a program during its symbolic execution. Therefore, the control flow or computation during the program’s execution, mainly in symbolic execution, can be represented as a directed graph named Control Flow Graph (CFG). In this work, we present the properties of the CFG and discuss the application of constraint programming techniques to reduce variable domains as a preprocessing step or during the BMC process for verifying software systems. We also describe how constraint programming can be exploited to prove the (partial) correctness of the program via proof by induction built on top of BMC
Sodium-glucose cotransporter 1 inhibition and gout: Mendelian randomization study
No full textObjective. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) reduce serum urate, but their efficacy depends on renal function which is often impaired in patients with gout. SGLT1 is primarily expressed in the small intestine and its inhibition may be a more suitable target for gout. We aimed to investigate the association of genetically proxied SGLT1i with gout risk, serum urate levels and cardiovascular safety using Mendelian randomization (MR).Methods. Leveraging data from a genome-wide association study of 344,182 individuals in the UK Biobank, we identified a missense variant in the SLC5A1 gene that associated with glycated haemoglobin (HbA1c) to proxy SGLT1i. Outcome genetic data comprised 13,179 gout cases and 750,634 controls, 457,690 individuals for serum urate levels, and up to 977,323 individuals for cardiovascular safety outcomes. We applied the Wald ratio method and investigated potential genetic confounding using colocalization.Results. The rs17683430 missense variant was selected to instrument SGLT1i. Genetically proxied SGLT1i was associated with 75% reduction in gout risk (OR 0.25; 95%CI 0.06, 0.99; p=0.048) and 32.0μmol/L reduction in serum urate (95%CI -56.7, -7.3; p=0.01), per 6.7mmol/mol reduction in HbA1c. SGLT1i was associated with increased levels of low-density lipoprotein cholesterol (0.37mmol/L; 95%CI 0.17, 0.56; p=0.0002) but not coronary heart disease, stroke, or chronic kidney disease. Colocalization did not suggest that the results are attributable to genetic confounding.Conclusion. SGLT1 inhibition may represent a novel therapeutic option for preventing gout in patients with or without comorbid diabetes. Randomised trials are needed to formally investigate efficacy and safety.Keywords: Sodium-glucose cotransporter, gout, urate, cholesterol, SGLT1, glycated haemoglobin, diabetes.<br/
