503 research outputs found
Explaining Aviation Safety Incidents Using Deep Temporal Multiple Instance Learning
Although aviation accidents are rare, safety incidents occur more frequently
and require a careful analysis to detect and mitigate risks in a timely manner.
Analyzing safety incidents using operational data and producing event-based
explanations is invaluable to airline companies as well as to governing
organizations such as the Federal Aviation Administration (FAA) in the United
States. However, this task is challenging because of the complexity involved in
mining multi-dimensional heterogeneous time series data, the lack of
time-step-wise annotation of events in a flight, and the lack of scalable tools
to perform analysis over a large number of events. In this work, we propose a
precursor mining algorithm that identifies events in the multidimensional time
series that are correlated with the safety incident. Precursors are valuable to
systems health and safety monitoring and in explaining and forecasting safety
incidents. Current methods suffer from poor scalability to high dimensional
time series data and are inefficient in capturing temporal behavior. We propose
an approach by combining multiple-instance learning (MIL) and deep recurrent
neural networks (DRNN) to take advantage of MIL's ability to learn using weakly
supervised data and DRNN's ability to model temporal behavior. We describe the
algorithm, the data, the intuition behind taking a MIL approach, and a
comparative analysis of the proposed algorithm with baseline models. We also
discuss the application to a real-world aviation safety problem using data from
a commercial airline company and discuss the model's abilities and
shortcomings, with some final remarks about possible deployment directions
Two remarks about nilpotent operators of order two
We present two novel results about Hilbert space operators which are
nilpotent of order two. First, we prove that such operators are indestructible
complex symmetric operators, in the sense that tensoring them with any operator
yields a complex symmetric operator. In fact, we prove that this property
characterizes nilpotents of order two among all nonzero bounded operators.
Second, we establish that every nilpotent of order two is unitarily equivalent
to a truncated Toeplitz operator.Comment: 7 pages. To appear in Proceedings of the AM
An Extremal Problem for Characteristic Functions
Suppose E is a subset of the unit circle T and Hinfinity C Linfinity is the Hardy subalgebra. We examine the problem of finding the distance from the characteristic function of E to znHinfinity. This admits an alternate description as a dual extremal problem. Precise solutions are given in several important cases. The techniques used involve the theory of Toeplitz and Hankel operators as well as the construction of certain conformal mappings
メキシコの半乾燥地における異なる有機物の施用効果
In semiarid areas of Mexico, lack of organic matter is a major constraint for production of corn and frijol beans, the main crops of the region. A multi-year experiment was carried out at the CENGUA Experiment Station, Guanajuato State, Mexico. Soil moisture was highest in the treatments with 100% or 67% of corn residues. Yields of frijol beans increased as the proportion of corn residues increased in all three years, but there was no significant difference between the treatment with all corn residues and the treatment with one-third reduction of corn residues in two of the three years. The
harvest index was highest in the same two treatments with higher proportions of corn residues in the last years. These results suggest that corn residues can be reduced by one third in fertilization of corn-frijol bean systems while maintaining adequate frijol bean yields. This could assist in
establishment of sustainable corn-frijol bean-cattle integrated agriculture in semi-arid areas of Mexico
Editorial. The crux in bridge and transport network resilience - advancements and future-proof solutions
Bridges and critical transport infrastructure (CTI) are primary infrastructure assets and systems that underpin human mobility and activities. Loss of the functionality of bridges has consequences on the entire transport network, which is also interconnected with other networks, therefore cascading events are expected in the entire system of systems, leading to significant economic losses, business, and societal disruption. Recent natural disasters revealed the vulnerabilities of bridges and CTI to diverse hazards (e.g. floods, blasts, earthquakes), some of which are exacerbated due to climate change. Therefore, the assessment of bridge and network vulnerabilities by quantifying their capacity and functionality loss and adaptation to new requirements and stressors is of paramount importance. In this paper, we try to understand what are the main compound hazards, stressors and threats that influence bridges with short- and long-term impacts on their structural capacity and functionality and the impact of bridge closures on the network operability. We also prioritise the main drivers of bridge restoration and reinstatement, e.g. its importance, structural, resources, organisational factors. The loss of performance, driven by the redundancy and robustness of the bridge, is the first step to be considered in the overall process of resilience quantification. Resourcefulness is the other main component of resilience here analysed
ResearchFanshawe Magazine Issue 6
https://first.fanshawec.ca/researchfanshawemag/1005/thumbnail.jp
Diagnostic and Therapeutic Management of Urinary Tract Infections in Catalonia, Spain: Protocol for an Observational Cohort Study
Urinary tract infection; Primary health care; Anti-bacterial agentsInfecció del tracte urinari; Atenció primària de salut; Agents antibacteriansInfección del tracto urinario; Atención primaria de salud; Agentes antibacterianosBackground:
Antibiotic resistance is an individual and public health problem; multidrug-resistant infections could cause an estimated 10 million deaths worldwide by 2050. Unnecessary use of antimicrobials is the most important cause of resistance generation in the community, and an estimated 80% of antimicrobials are prescribed in primary health care, frequently for urinary tract infections (UTIs).
Objective:
This paper presents the protocol for the first phase of the Urinary Tract Infections in Catalonia (Infeccions del tracte urinari a Catalunya) project. We aim to examine the epidemiology of the different types of UTIs in Catalonia (an autonomous community in Spain) and their diagnostic and therapeutic management by health professionals. Furthermore, we aim to evaluate the correlation between types and total consumption of antibiotics for recurrent UTIs in 2 cohorts of women with the presence and severity of infectious complications of urological origin, especially pyelonephritis and sepsis, and 2 potentially serious infections: pneumonia and COVID-19.
Methods:
The study is a population-based observational cohort study including adults with a diagnosis of UTI registered in the Information System for the Development of Research in Primary Care (in Catalan: Sistema d’informació per al desenvolupament de la investigació en atenció primària), the Minimum Basic Data Sets of Hospital Discharges and Emergency Departments (in Catalan: Conjunt mínim bàsic de dades a l’hospitalització d'aguts i d’atenció urgent), and data from the Hospital Dispensing Medicines Register (in Catalan: Medicació hospitalària de dispensació ambulatòria) of Catalonia from the period between 2012 and 2021. We will evaluate the variables obtained from the databases to analyze the proportion of different types of UTIs, the percentage of adequate antibiotic treatments prescribed or received for recurrent UTIs according to the national guidelines, and the proportion of UTIs with complications.
Results:
We expect to describe the epidemiology of UTIs in Catalonia from 2012 to 2021, as well as describe the diagnostic and therapeutic management of UTIs by health professionals.
Conclusions:
We expect to find a high percentage of UTI cases with inadequate management according to the national guidelines, considering that on many occasions UTIs are treated with second- or third-line antibiotic therapies with a preference for the longest regimens. Furthermore, the use of antibiotic suppressive therapies, or prophylaxis, in recurrent UTIs will likely be highly variable. Moreover, we aim to determine whether women with recurrent UTIs treated with antibiotic suppressive therapies have a higher incidence and severity of potentially serious future infections, with special attention to acute pyelonephritis, urosepsis, COVID-19, and pneumonia, compared to women who receive antibiotic treatment after they present with a UTI. This is an observational study of data from administrative databases that will not allow causality analysis. The limitations of the study will be handled according to the appropriate statistical methods
Patterns of radiological response to tebentafusp in patients with metastatic uveal melanoma
Metastatic uveal melanoma (mUM) is a rare type of melanoma with poor outcomes. The first systemic treatment to significantly prolong overall survival (OS) in patients with mUM was tebentafusp, a bispecific protein that can redirect T-cells to gp-100 positive cells. However, the objective response rate according to Response Evaluation Criteria in Solid Tumors (RECIST) may underestimate the clinical impact of tebentafusp. As metabolic response assessed by PET Response Criteria in Solid Tumors (PERCIST) has been reported to better correlate with clinical outcome, we here compared the patterns of radiological and morphological responses in HLA-A*02:01-positive patients with mUM treated with tebentafusp. In the 19 enrolled patients, RECIST showed an overall response rate (ORR) of 10%, median progression-free survival of 2.8 months (95% CI 2.5–8.4), and median OS (mOS) of 18.8 months. In 10 patients, where both RECIST and PERCIST evaluation was available, the ORR was 10% for both; however, the PFS was longer for PERCIST compared to RECIST, 3.1 and 2.4 months, respectively. A poor agreement between the criteria was observed at all assessments (Cohen’s kappa ≤0), yet they differed significantly only at the first on-treatment imaging (P = 0.037). Elevated baseline LDH and age were associated with an increased risk for RECIST progression, while lymphocyte decrease after the first infusions correlated to reduced risk of RECIST progression. Detectable ctDNA at baseline did not correlate with progression. Early response to tebentafusp may be incompletely captured by conventional imaging, leading to a need to consider both tumor morphology and metabolism
Recommended from our members
Computational Knowledge Integration in Biopharmaceutical Research
An initiative to increase biopharmaceutical research productivity by capturing, sharing and computationally integrating proprietary scientific discoveries with public knowledge is described. This initiative involves both organisational process change and multiple interoperating software systems. The software components rely on mutually supporting integration techniques. These include a richly structured ontology, statistical analysis of experimental data against stored conclusions, natural language processing of public literature, secure document repositories with lightweight metadata, web services integration, enterprise web portals and relational databases. This approach has already begun to increase scientific productivity in our enterprise by creating an organisational memory (OM) of internal research findings, accessible on the web. Through bringing together these components it has also been possible to construct a very large and expanding repository of biological pathway information linked to this repository of findings which is extremely useful in analysis of DNA microarray data. This repository, in turn, enables our research paradigm to be shifted towards more comprehensive systems-based understandings of drug action
Effectiveness of antitussives, anticholinergics or honey versus usual care in adults with uncomplicated acute bronchitis : a study protocol of an open randomised clinical trial in primary care
Introduction Despite the frequent use of therapies in acute bronchitis, the evidence of their benefit is lacking, since only a few clinical trials have been published, with low sample sizes, poor methodological quality and mainly in children. The objective of this study is to compare the effectiveness of three symptomatic therapies (dextromethorphan, ipratropium or honey) associated with usual care and the usual care in adults with acute bronchitis. Methods and analysis This will be a multicentre, pragmatic, parallel group, open randomised trial. Patients aged 18 or over with uncomplicated acute bronchitis, with cough for less than 3 weeks as the main symptom, scoring ≥4 in either daytime or nocturnal cough on a 7-point Likert scale, will be randomised to one of the following four groups: usual care, dextromethorphan 30 mg three times a day, ipratropium bromide inhaler 20 μg two puffs three times a day or honey 30 mg (a spoonful) three times a day, all taken for up to 14 days. The exclusion criteria will be pneumonia, criteria for hospital admission, pregnancy or lactation, concomitant pulmonary disease, associated significant comorbidity, allergy, intolerance or contraindication to any of the study drugs or admitted to a long-term residence. Sample: 668 patients. The primary outcome will be the number of days with moderate-to-severe cough. All patients will be given a paper-based symptom diary to be self-administered. A second visit will be scheduled at day 2 or 3 for assessing evolution, with two more visits at days 15 and 29 for clinical assessment, evaluation of adverse effects, re-attendance and complications. Patients still with symptoms at day 29 will be called 6 weeks after the baseline visit. Ethics and dissemination The study has been approved by the Ethical Board of IDIAP Jordi Gol (reference number: AC18/002). The findings of this trial will be disseminated through research conferences and peer-review journals. Trial registration number NCT03738917; Pre-results
- …