A quasi-real-time ground-based trajectory optimization tool for greener operations

This paper describes the methodology adopted in designing a quasi-real-time ground-based trajectory optimization tool for use by air traffic control officers. The tool is primarily intended for the optimization of aircraft trajectories during the climb and descent phases in which the user can define the trajectory in four dimensions. The optimized trajectories would then contribute to a reduction in fuel burn and emissions. The designed tool takes into account different aircraft types and sub-types through BADA performance and engine coefficients. A simple case study for an approach in Malta International Airport has also been presented to illustrate the use of the tool.peer-reviewe

A generic framework for multi-parameter optimization of flight trajectories

The project is co-funded by the European Community’s Seventh Framework Programme (FP7/2007-2013) for the Clean Sky Joint Technology Initiative.This paper presents the requirements and design concept of a multi-parameter optimization tool to be used on flight trajectories. The tool, referred to as GATAC, is being developed as part of the EU-funded Clean Sky Joint Technology Initiative (JTI) programme, and a preliminary version is discussed in this paper. The tool has been evaluated and the results obtained confirm the validity of the tool, opening the way for further development. The paper also addresses the architectural design and a number of key features of the tool.peer-reviewe

A flexible framework for configurable real-time flight simulators

This paper presents the design and development of a Simulation and Integration Framework for use in research and teaching simulators. The design of the framework facilitates the integration of different simulation models of various formats without the need of software programming skills in a simulation environment. This is achieved through a Graphical User Interface (GUI) allowing the user to easily set up a flight simulator utilizing models programmed in different languages and having different interfaces. The framework allows for dynamic parallel processing over a distributed system providing the capability of concurrent model processing.peer-reviewe

GATAC - A generic framework for multi-parameter optimization of flight trajectories

Simulations in different scenarios requires the use of various models, the interfacing of which typically requires extensive effort and programming resources that may not be readily available in most industrial and academic environments. This paper discusses the development of GATAC - a generic framework that was developed for simulation and multiparameter optimization purposes allowing users to easily set up a simulation by making use of models developed using different technologies with different interfaces.peer-reviewe

Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study

BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (VT). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients.OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference.DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries.MAIN OUTCOME MEASURES: Women and men were compared with respect to use of LTVV, defined as VT of 8 ml kg-1 or less predicted bodyweight (PBW). A VT was deemed 'default' if the set VT was a round number. A mediation analysis assessed which factors may explain the sex difference in use of LTVV during intra-operative ventilation.RESULTS: This analysis includes 9864 patients, of whom 5425 (55%) were women. A default VT was often set, both in women and men; mode VT was 500 ml. Median [IQR] VT was higher in women than in men (8.6 [7.7 to 9.6] vs. 7.6 [6.8 to 8.4] ml kg-1 PBW, P < 0.001). Compared with men, women were twice as likely not to receive LTVV [68.8 vs. 36.0%; relative risk ratio 2.1 (95% CI 1.9 to 2.1), P < 0.001]. In the mediation analysis, patients' height and actual body weight (ABW) explained 81 and 18% of the sex difference in use of LTVV, respectively; it was not explained by the use of a default VT.CONCLUSION: In this worldwide cohort of patients receiving intra-operative ventilation during general anaesthesia for surgery, women received a higher VT than men during intra-operative ventilation. The risk for a female not to receive LTVV during surgery was double that of males. Height and ABW were the two mediators of the sex difference in use of LTVV.TRIAL REGISTRATION: The study was registered at Clinicaltrials.gov, NCT01601223

Income Inequality in Canada at the National and Subnational Levels 1982-2021

In this paper we estimate the distribution of all national income in Canada, and five sub-regions, from 1982 to 2021. We apply distributional national accounts (DINA) methodology to tax tabulations, combined with national accounts data and survey data. Pre-tax and post-tax income data are analysed. We find that top income shares published by Statistics Canada tend to underestimate income inequality relative to top income shares calculated using DINA, as DINA account for people who do not file taxes and for undistributed capital income that is retained in corporations. In line with previous research, income inequality in Canada increased significantly from 1982 until the mid-2000s. From 1982 until 2000, the real income of the bottom 50% of Canadians stagnated while that of the top 0.01% quadrupled. Since the mid-2000s, income inequality has decreased slightly although it remains far above the levels observed in the early 1980s. Across Canadian provinces, Ontario has consistently had higher inequality than Quebec although the gap has closed in recent years. Quebec has the most progressive tax and transfer system of the six sub-regions. In Alberta, record levels of inequality were reached in the mid-2000s and these appear to have been a significant driver of the national peak in inequality during this period. Post-tax income inequality initially fell during the pandemic because large temporary transfer programs were introduced. However, pre-tax income inequality increased, especially in 2021 when record levels of corporate profits were reached

A quasi-real-time ground-based trajectory optimization tool for greener operations

This paper describes the methodology adopted in designing a quasi-real-time ground-based trajectory optimization tool for use by air traffic control officers. The tool is primarily intended for the optimization of aircraft trajectories during the climb and descent phases in which the user can define the trajectory in four dimensions. The optimized trajectories would then contribute to a reduction in fuel burn and emissions. The designed tool takes into account different aircraft types and sub-types through BADA performance and engine coefficients. A simple case study for an approach in Malta International Airport has also been presented to illustrate the use of the tool. peer-reviewe

White matter perivascular spaces: An MRI marker in pathology-proven cerebral amyloid angiopathy?

Objective: We investigated whether severe, MRI-visible perivascular spaces (PVS) in the cerebral hemisphere white matter (centrum semiovale) are more common in patients with pathologyproven cerebral amyloid angiopathy (CAA) than in those with pathology-proven non-CAA-related intracerebral hemorrhage (ICH). Methods: Using a validated 4-point scale on axial T2-weighted MRI, we compared PVS in patients with pathology-proven CAA to PVS in those with spontaneous ICH but no histopathologic evidence of CAA. In a preliminary analysis restricted to patients with T2*-weighted gradient-recalled echo MRI, we also investigated whether including severe centrum semiovale PVS increases the sensitivity of existing diagnostic criteria for probable CAA. Results: Fourteen patients with CAA and 10 patients with non-CAA-related ICH were included. Eight of the patients with CAA were admitted for symptomatic, spontaneous lobar ICH, 1 because of ischemic stroke, 1 with transient focal neurologic episodes, and 4 due to cognitive decline. Severe (>20) centrum semiovale PVS were more frequent in patients with CAA compared to controls (12/14 [85.7%; 95% confidence interval (CI): 57.2%-98.2%] vs 0/10 [1-sided 95% CI: 0%-30.8%], p < 0.0005); this was robust to adjustment for age. The original Boston criteria for probable CAA showed a sensitivity of 76.9% (95% CI: 46.2%-95%), which increased to 92.3% (95% CI: 64%-99.8%), without loss of specificity, after including severe centrum semiovale PVS. Conclusions: Severe centrum semiovale PVS on MRI may be a promising new neuroimaging marker for the in vivo diagnosis of CAA. However, our findings are preliminary and require confirmation and external validation in larger cohorts of pathology-proven CAA. © 2013 American Academy of Neurology

Magneto-optical trapping and background-free imaging for atoms near nanostructured surfaces

We demonstrate a combined magneto-optical trap and imagingsystem that is suitable for the investigation of cold atoms near surfaces. In particular, we are able to trap atoms close to optically scattering surfaces andto image them with an excellent signal-to-noise ratio. We also demonstrate a simple magneto-optical atom cloud launching method. We anticipate that this system will be useful for a range of experimental studies of novelatom-surface interactions and atom trap miniaturization.<br/

Whole-genome sequencing identifies EN1 as a determinant of bone density and fracture

The extent to which low-frequency (minor allele frequency (MAF) between 1-5%) and rare (MAF ≤ 1%) variants contribute to complex traits and disease in the general population is mainly unknown. Bone mineral density (BMD) is highly heritable, a major predictor of osteoporotic fractures, and has been previously associated with common genetic variants, as well as rare, population-specific, coding variants. Here we identify novel non-coding genetic variants with large effects on BMD (ntotal = 53,236) and fracture (ntotal = 508,253) in individuals of European ancestry from the general population. Associations for BMD were derived from whole-genome sequencing (n = 2,882 from UK10K (ref. 10); a population-based genome sequencing consortium), whole-exome sequencing (n = 3,549), deep imputation of genotyped samples using a combined UK10K/1000 Genomes reference panel (n = 26,534), and de novo replication genotyping (n = 20,271). We identified a low-frequency non-coding variant near a novel locus, EN1, with an effect size fourfold larger than the mean of previously reported common variants for lumbar spine BMD (rs11692564(T), MAF = 1.6%, replication effect size = +0.20 s.d., Pmeta = 2 × 10(-14)), which was also associated with a decreased risk of fracture (odds ratio = 0.85; P = 2 × 10(-11); ncases = 98,742 and ncontrols = 409,511). Using an En1(cre/flox) mouse model, we observed that conditional loss of En1 results in low bone mass, probably as a consequence of high bone turnover. We also identified a novel low-frequency non-coding variant with large effects on BMD near WNT16 (rs148771817(T), MAF = 1.2%, replication effect size = +0.41 s.d., Pmeta = 1 × 10(-11)). In general, there was an excess of association signals arising from deleterious coding and conserved non-coding variants. These findings provide evidence that low-frequency non-coding variants have large effects on BMD and fracture, thereby providing rationale for whole-genome sequencing and improved imputation reference panels to study the genetic architecture of complex traits and disease in the general population.</p