Numerical inverse scattering for the Korteweg–-de Vries and modified Korteweg–-de Vries equations

Recent advances in the numerical solution of Riemann–Hilbert problems allow for the implementation of a Cauchy initial value problem solver for the Korteweg–de Vries equation (KdV) and the defocusing modified Korteweg–de Vries equation (mKdV), without any boundary approximation. Borrowing ideas from the method of nonlinear steepest descent, this method is demonstrated to be asymptotically accurate. The method is straightforward for the case of defocusing mKdV due to the lack of poles in the Riemann–Hilbert problem and the boundedness properties of the reflection coefficient. Solving KdV requires the introduction of poles in the Riemann–Hilbert problem and more complicated deformations. The introduction of a new deformation for KdV allows for the stable asymptotic computation of the solution in the entire (x, t)-plane. KdV and mKdV are dispersive equations and this method can fully capture the dispersion with spectral accuracy. Thus, this method can be used as a benchmarking tool for determining the effectiveness of future numerical methods designed to capture dispersion. This method can easily be adapted to other integrable equations with Riemann–Hilbert formulations, such as the nonlinear Schrödinger equation

The Orphan Receptor CRF2-4 Is an Essential Subunit of the Interleukin 10 Receptor

The orphan receptor CRF2-4 is a member of the class II cytokine receptor family (CRF2), which includes the interferon receptors, the interleukin (IL) 10 receptor, and tissue factor. CRFB4, the gene encoding CRF2-4, is located within a gene cluster on human chromosome 21 that comprises three interferon receptor subunits. To elucidate the role of CRF2-4, we disrupted the CRFB4 gene in mice by means of homologous recombination. Mice lacking CRF2-4 show no overt abnormalities, grow normally, and are fertile. CRF2-4 deficient cells are normally responsive to type I and type II interferons, but lack responsiveness to IL-10. By ∼12 wk of age, the majority of mutant mice raised in a conventional facility developed a chronic colitis and splenomegaly. Thus, CRFB4 mutant mice recapitulate the phenotype of IL-10–deficient mice. These findings suggest that CRF2-4 is essential for IL-10–mediated effects and is a subunit of the IL-10 receptor

Unmet need and psychological distress predict emergency department visits in community-dwelling elderly women: a prospective cohort study

<p>Abstract</p> <p>Background</p> <p>Unmet need to perform activities of daily living (ADL) is associated with increased use of urgent health services by the elderly. However, the reported associations may be confounded by psychological distress. We examine the independent effects of unmet need and psychological distress upon emergency department (ED) visits.</p> <p>Methods</p> <p>We conducted a prospective study of randomly selected community-dwelling adults aged ≥ 75. We report here the results for women only (n = 530). In-person interviews collected data on self-reported unmet need and the 14-item <it>l'Indice de détresse psychologique de Santé Québec </it>psychological distress scale. ED visits were identified from an administrative database. Multivariable logistic regression was used to identify predictors of any ED visit in the 6 months following the baseline interview.</p> <p>Results</p> <p>In multivariable analysis, unmet need in instrumental ADL was associated with subsequent ED visits (odds ratio = 1.57, 95% confidence interval = 1.02-2.41), as was psychological distress (odds rate = 1.30, 95% confidence interval = 1.02-1.67). The magnitude of the association between unmet need and ED visits was overestimated in statistical models that did not adjust for psychological distress.</p> <p>Conclusions</p> <p>Both unmet need and psychological distress were independent predictors of ED visits. Future investigations of unmet need and health services utilization should include psychological distress to control for confounding and improve the internal validity of statistical models.</p

The interest of gait markers in the identification of subgroups among fibromyalgia patients

<p>Abstract</p> <p>Background</p> <p>Fibromyalgia (FM) is a heterogeneous syndrome and its classification into subgroups calls for broad-based discussion. FM subgrouping, which aims to adapt treatment according to different subgroups, relies in part, on psychological and cognitive dysfunctions. Since motor control of gait is closely related to cognitive function, we hypothesized that gait markers could be of interest in the identification of FM patients' subgroups. This controlled study aimed at characterizing gait disorders in FM, and subgrouping FM patients according to gait markers such as stride frequency (SF), stride regularity (SR), and cranio-caudal power (CCP) which measures kinesia.</p> <p>Methods</p> <p>A multicentre, observational open trial enrolled patients with primary FM (44.1 ± 8.1 y), and matched controls (44.1 ± 7.3 y). Outcome measurements and gait analyses were available for 52 pairs. A 3-step statistical analysis was carried out. A preliminary single blind analysis using k-means cluster was performed as an initial validation of gait markers. Then in order to quantify FM patients according to psychometric and gait variables an open descriptive analysis comparing patients and controls were made, and correlations between gait variables and main outcomes were calculated. Finally using cluster analysis, we described subgroups for each gait variable and looked for significant differences in self-reported assessments.</p> <p>Results</p> <p>SF was the most discriminating gait variable (73% of patients and controls). SF, SR, and CCP were different between patients and controls. There was a non-significant association between SF, FIQ and physical components from Short-Form 36 (p = 0.06). SR was correlated to FIQ (p = 0.01) and catastrophizing (p = 0.05) while CCP was correlated to pain (p = 0.01). The SF cluster identified 3 subgroups with a particular one characterized by normal SF, low pain, high activity and hyperkinesia. The SR cluster identified 2 distinct subgroups: the one with a reduced SR was distinguished by high FIQ, poor coping and altered affective status.</p> <p>Conclusion</p> <p>Gait analysis may provide additional information in the identification of subgroups among fibromyalgia patients. Gait analysis provided relevant information about physical and cognitive status, and pain behavior. Further studies are needed to better understand gait analysis implications in FM.</p

(Cost)-effectiveness of family meetings on indicated prevention of anxiety and depressive symptoms and disorders of primary family caregivers of patients with dementia: design of a randomized controlled trial

Contains fulltext : 70773.pdf (publisher's version ) (Open Access)BACKGROUND: Dementia is a major public health problem with enormous costs to society and major consequences for both patients and their relatives. Family members of persons with dementia provide much of the care for older adults with dementia in the community. Caring for a demented relative is not easy and fraught with emotional strain, distress, and physical exhaustion. Family caregivers of dementia patients have an extremely high risk developing affective disorders such as major depression and anxiety disorder. Family meetings appear to be among the most powerful psychosocial interventions to reduce depression in caregivers.An American landmark study reported substantial beneficial effects of a multifaceted intervention where family meetings had a central place on depression in family caregivers as well as on delay of institutionalization of patients. These effects were not replicated in other countries yet. We perform the first trial comparing only structured family meetings with significant others versus usual care among primary family caregivers of community dwelling demented patients and measure the effectiveness on both depression and anxiety in the primary caregiver, both on disorder and symptom levels. METHODS/DESIGN: In this randomized controlled trial effectiveness as well as cost-effectiveness of family meetings is evaluated. The intervention group receives four family meetings with family and close friends of the primary family caregiver of a community dwelling patient with a clinical diagnosis of dementia. Dyads of patients and their primary caregiver are followed up to one year after baseline assessment. The main outcome measures are the incidence of anxiety and depressive disorders assessed with the Mini-International Neuropsychiatric Interview (MINI) and the severity of anxiety and depressive symptoms in caregivers is measured by validated self report instruments: the Centre for Epidemiologic Studies Depression Scale (CES-D) for depression and the anxiety scales of the Hospital Anxiety and Depression scales (HADS) for anxiety. The economic evaluation is performed from a societal perspective. DISCUSSION: By evaluating the effectiveness of only structured family meetings organized in the Netherlands, this study will contribute to the existing literature about the value of psychosocial interventions for dementia caregivers. TRIAL REGISTRATION: Dutch Trial Registry ISRCTN90163486

The Mid-infrared Instrument for JWST and Its In-flight Performance

The Mid-Infrared Instrument (MIRI) extends the reach of the James Webb Space Telescope (JWST) to 28.5 μm. It provides subarcsecond-resolution imaging, high sensitivity coronagraphy, and spectroscopy at resolutions of λ/Δλ ∼ 100-3500, with the high-resolution mode employing an integral field unit to provide spatial data cubes. The resulting broad suite of capabilities will enable huge advances in studies over this wavelength range. This overview describes the history of acquiring this capability for JWST. It discusses the basic attributes of the instrument optics, the detector arrays, and the cryocooler that keeps everything at approximately 7 K. It gives a short description of the data pipeline and of the instrument performance demonstrated during JWST commissioning. The bottom line is that the telescope and MIRI are both operating to the standards set by pre-launch predictions, and all of the MIRI capabilities are operating at, or even a bit better than, the level that had been expected. The paper is also designed to act as a roadmap to more detailed papers on different aspects of MIRI

Factors associated with breastfeeding initiation:A comparison between France and French-speaking Canada

Background: Breastfeeding is associated with multiple domains of health for both mothers and children. Nevertheless, breastfeeding initiation is low within certain developed countries. Furthermore, comparative studies of initiation rates using harmonised data across multiple regions is scarce. Objective: The aim of the present study was to investigate and compare individual-level determinants of breastfeeding initiation using two French-speaking cohorts. Methods: Participants included ~ 3,900 mothers enrolled in two cohort studies in Canada and France. Interviews, questionnaires, and medical records were utilised to collect information on maternal, family, and medical factors associated with breastfeeding initiation. Results: Rates of breastfeeding initiation were similar across cohorts, slightly above 70%. Women in both Canada and France who had higher levels of maternal education, were born outside of their respective countries and who did not smoke during pregnancy were more likely to initiate breastfeeding with the cohort infant. Notably, cohort effects of maternal education at the university level were found, whereby having 'some university' was not statistically significant for mothers in France. Further, younger mothers in Canada, who delivered by caesarean section and who had previous children had reduced odds of breastfeeding initiation. These results were not found for mothers in France. Conclusions and Implications for Practice: While some similar determinants were observed, programming efforts to increase breastfeeding initiation should be tailored to the characteristics of specific geographical regions which may be heavily impacted by the social, cultural and political climate of the region, in addition to individual and family level factors.European Commission - Seventh Framework Programme (FP7