Cyberbotics Ltd. develops Webots TM , a mobile robotics simulation software that provides you with a rapid prototyping environment for modelling, programming and simulating mobile robots. The provided robot libraries enable you to transfer your control programs to several commercially available real mobile robots. Webots TM lets you define and modify a complete mobile robotics setup, even several different robots sharing the same environment. For each object, you can define a number of properties, such as shape, color, texture, mass, friction, etc. You can equip each robot with a large number of available sensors and actuators. You can program these robots using your favorite development environment, simulate them and optionally transfer the resulting programs onto your real robots. Webots TM has been developed in collaboration with the Swiss Federal Institute of Technology in Lausanne, thoroughly tested, well documented and continuously maintained for over 7 years. It is now the main commercial product available from Cyberbotics Ltd.
In sensitized subjects, exposure to the mite allergen appears to be only one of several factors leading to asthma. We hypothesized that in association with allergen exposure, endotoxin, a proinflammatory agent present in house dust (HD), influences the severity of asthma. Using a cross-sectional study design, we investigated a group of 69 consecutive dust mite (HDM)-sensitized subjects defined as having rhinitis (n = 20) or asthma (n = 49); the latter were evaluated functionally and clinically by three different scores and by their need for daily medication. Concentrations of Dermatophagoides pteronyssinus p I allergen (Der p I) (by two-site monoclonal antibody enzyme-linked immunosorbent assay [ELISA]), guanine (by high-pressure liquid chromatography [HPLC]), and endotoxin (by modified Limulus. amebocyte lysate assay) were measured in HD collected in duplicate from the mattresses and floors in each subject's home. The concentrations of Der p I and of guanine in HD collected from mattresses were significantly higher in asthmatic subjects than in those with rhinitis (p < 0.05 and < 0.04, respectively). In subjects (n = 37) exposed to a high level of HDM allergen (i.e., Der p I > or = 10 micrograms/g HD and/or guanine > or = 0.10 mg/100 mg HD), the severity of asthma was unrelated to mite allergen concentration in HD. On the contrary, the severity of asthma was related to concomitant exposure to endotoxin in HD, since the concentration of HD endotoxin was significantly and inversely correlated with FEV1 (p < 0.05), FEV1/FVC (p < 0.02), daily need for oral (p < 0.01) and inhaled (p < 0.01) corticosteroids, daily need for beta 2 agonists (p < 0.001) and xanthines (p < 0.01), and clinical scores such as the modified Aas score (p < 0.01). In HDM-sensitized subjects exposed to a high level of allergen, the concentration of endotoxin measured in HD is an important determinant of asthma severity.
We have developed a new experimental technique to measure the Lagrangian velocity of tracer particles in a turbulent flow, based on ultrasonic Doppler tracking. This method yields a direct access to the velocity of a single particle at a turbulent Reynolds number R(lambda) = 740, with two decades of time resolution, below the Lagrangian correlation time. We observe that the Lagrangian velocity spectrum has a Lorentzian form E(L)(omega) = u(2)(rms)T(L)/[1+(T(L)omega)(2)], in agreement with a Kolmogorov-like scaling in the inertial range. The probability density functions of the velocity time increments display an intermittency which is more pronounced than that of the corresponding Eulerian spatial increments.
Exposure to endotoxin and to its purified derivative lipopolysaccharide (LPS) is related to several occupational pulmonary diseases and to severe domestic asthma. An inhalation of a given dose of pure LPS produces both a systemic and a bronchial inflammatory response. Information on the dose-response relationship to inhaled LPS in normal subjects is a prerequisite to define the safety threshold of exposure. In the present study, the clinical and inflammatory responses to rising doses of inhaled LPS was evaluated. Nine normal volunteers were challenged weekly by inhalation with saline, 0.5, 5, and 50 microg LPS (Escherichia coli). The response determinators are the clinical symptoms, fever, FEV1, blood polymorphonuclear neutrophils (PMNs) with their level of activation (measured by luminol enhanced-chemiluminescence), and both the blood and the urine concentrations of the C-reactive protein (CRP). To assess the bronchial inflammatory response, an induced sputum was obtained 6 h after each dose of LPS, and the total and differential cell counts as well as the MPO, ECP, and TNF-alpha concentrations were measured. Compared with the saline, an inhalation of 0.5 microg LPS induces a significant decrease in the PMN luminol-enhanced chemiluminescence (p < 0.01), which could reflect a process of margination and/or extravascular sequestration of activated PMN. Inhalation of 5 microg LPS is associated with a significant rise in blood CRP (p < 0.01) and PMNs (p < 0.001) and in sputum PMNs (p < 0.05), monocytes (p < 0.05), and MPO (p < 0.05). Inhalation of 50 microg LPS was characterized by a significant increase in temperature (p < 0.01), blood PMNs (p < 0.001), blood and urine CRP (p < 0.01 and < 0.01), and sputum PMNs (p < 0.001), monocytes (p < 0.05), lymphocytes (p < 0.05), MPO (p < 0.01), TNF-alpha (p < 0.01), and ECP (p < 0.01) while five subjects develop symptoms. In normal subjects, the response to inhaled LPS is dose-related, the most sensitive markers of LPS-induced inflammation being the blood PMNs count with their level of activation, the blood CRP concentration, and the sputum PMNs count. The no-response threshold to an acute inhalation of LPS is less than 0.5 microg.
Geography and landscape are important determinants of genetic variation in natural populations, and several ancestry estimation methods have been proposed to investigate population structure using genetic and geographic data simultaneously. Those approaches are often based on computer-intensive stochastic simulations and do not scale with the dimensions of the data sets generated by high-throughput sequencing technologies. There is a growing demand for faster algorithms able to analyse genomewide patterns of population genetic variation in their geographic context. In this study, we present TESS3, a major update of the spatial ancestry estimation program TESS. By combining matrix factorization and spatial statistical methods, TESS3 provides estimates of ancestry coefficients with accuracy comparable to TESS and with run-times much faster than the Bayesian version. In addition, the TESS3 program can be used to perform genome scans for selection, and separate adaptive from nonadaptive genetic variation using ancestral allele frequency differentiation tests. The main features of TESS3 are illustrated using simulated data and analysing genomic data from European lines of the plant species Arabidopsis thaliana.
Background Cancer patients are thought to have an increased risk of developing severe Coronavirus Disease 2019 (COVID-19) infection and of dying from the disease. In this work, predictive factors for COVID-19 severity and mortality in cancer patients were investigated. Patients and Methods In this large nationwide retro-prospective cohort study, we collected data on patients with solid tumours and COVID-19 diagnosed between March 1 and June 11, 2020. The primary endpoint was all-cause mortality and COVID-19 severity, defined as admission to an intensive care unit (ICU) and/or mechanical ventilation and/or death, was one of the secondary endpoints. Results From April 4 to June 11, 2020, 1289 patients were analysed. The most frequent cancers were digestive and thoracic. Altogether, 424 (33%) patients had a severe form of COVID-19 and 370 (29%) patients died. In multivariate analysis, independent factors associated with death were male sex (odds ratio 1.73, 95%CI: 1.18-2.52), ECOG PS ≥ 2 (OR 3.23, 95%CI: 2.27-4.61), updated Charlson comorbidity index (OR 1.08, 95%CI: 1.01-1.16) and admission to ICU (OR 3.62, 95%CI 2.14-6.11). The same factors, age along with corticosteroids before COVID-19 diagnosis, and thoracic primary tumour site were independently associated with COVID-19 severity. None of the anticancer treatments administered within the previous 3 months had any effect on mortality or COVID-19 severity, except cytotoxic chemotherapy in the subgroup of patients with detectable SARS-CoV-2 by RT-PCR, which was associated with a slight increase of the risk of death (OR 1.53; 95%CI: 1.00-2.34; p = 0.05). A total of 431 (39%) patients had their systemic anticancer treatment interrupted or stopped following diagnosis of COVID-19. Conclusions Mortality and COVID-19 severity in cancer patients are high and are associated with general characteristics of patients. We found no deleterious effects of recent anticancer treatments, except for cytotoxic chemotherapy in the RT-PCR-confirmed subgroup of patients. In almost 40% of patients, the systemic anticancer therapy was interrupted or stopped after COVID-19 diagnosis.
The pool chlorine hypothesis postulates that the rise in childhood asthma in the developed world could result at least partly from the increasing exposure of children to toxic gases and aerosols contaminating the air of indoor chlorinated pools. To further assess this hypothesis, we explored the relationships between childhood asthma, atopy, and cumulated pool attendance (CPA). We studied 341 schoolchildren 10–13 years of age who attended at a variable rate the same public pool in Brussels (trichloramine in air, 0.3–0.5 mg/m3). Examination of the children included a questionnaire, an exercise-induced bronchoconstriction (EIB) test, and the measurement of exhaled nitric oxide (eNO) and total and aeroallergen-specific serum IgE. CPA by children (range, 0–1,818 hr) emerged among the most consistent predictors of asthma (doctor diagnosed or screened with the EIB test) and of elevated eNO, ranking immediately after atopy and family history of asthma or hay fever. Although the risk of elevated eNO increased with CPA [odds ratio (OR) = 1.30; 95% confidence interval (CI), 1.10–1.43] independently of total or specific serum IgE, the probability of developing asthma increased with CPA only in children with serum IgE > 100 kIU/L (OR for each 100-hr increase in CPA = 1.79; 95% CI, 1.07–2.72). All these effects were dose related and most strongly linked to pool attendance before 6–7 years of age. Use of indoor chlorinated pools especially by young children interacts with atopic status to promote the development of childhood asthma. These findings further support the hypothesis implicating pool chlorine in the rise of childhood asthma in industrialized countries.
Abstract-The generalized entropies of Rényi inspire new measures for estimating signal information and complexity in the time-frequency plane. When applied to a time-frequency representation (TFR) from Cohen's class or the affine class, the Rényi entropies conform closely to the notion of complexity that we use when visually inspecting time-frequency images. These measures possess several additional interesting and useful properties, such as accounting and cross-component and transformation invariances, that make them natural for time-frequency analysis. This paper comprises a detailed study of the properties and several potential applications of the Rényi entropies, with emphasis on the mathematical foundations for quadratic TFRs. In particular, for the Wigner distribution, we establish that there exist signals for which the measures are not well defined.
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