2,235 research outputs found

    A SAURON view of galaxies

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    We have measured the two-dimensional kinematics and line-strength distributions of 72 representative nearby early-type galaxies, out to approximately one effective radius, with our panoramic integral-field spectrograph SAURON. The resulting maps reveal a rich variety in kinematical structures and linestrength distributions, indicating that early-type galaxies are more complex systems than often assumed. We are building detailed dynamical models for these galaxies, to derive their intrinsic shape and dynamical structure, and to determine the mass of the supermassive central black hole. Here we focus on two examples, the compact elliptical M32 and the E3 galaxy NGC4365. These objects represent two extreme cases: M32 has very regular kinematics which can be represented accurately by an axisymmetric model in which all stars rotate around the short axis, while NGC4365 is a triaxial galaxy with a prominent kinematically decoupled core, with an inner core that rotates about an axis that is nearly perpendicular to the rotation axis of the main body of the galaxy. Our dynamical models for these objects demonstrate that two-dimensional observations are essential for deriving the intrinsic orbital structure and dark matter content of galaxies.Comment: 7 pages (3 figures, full resolution Fig. 1 available at http://www.strw.leidenuniv.nl/~verolme/M32.ps). Contributed talk to the Athens Workshop on Galaxies and Chaos, Theory and Observations; Proceedings to appear in "Galaxies and Chaos", eds. G. Contopoulos and N. Vogli

    Case finding of mild cognitive impairment and dementia and subsequent care; results of a cluster RCT in primary care

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    Purpose Despite a call for earlier diagnosis of dementia, the diagnostic yield of case finding and its impact on the mental health of patients and relatives are unclear. This study assessed the effect of a two-component intervention of case finding and subsequent care on these outcomes. Methods In a cluster RCT we assessed whether education of family physicians (FPs; trial stage 1) resulted in more mild cognitive impairment (MCI) and dementia diagnoses among older persons in whom FPs suspected cognitive decline and whether case finding by a practice nurse and the FP (trial stage 2) added to this number of diagnoses. In addition, we assessed mental health effects of case finding and subsequent care (trial stage 2). FPs of 15 primary care practices (PCPs = clusters) judged the cognitive status of all persons ≤ 65 years. The primary outcome, new MCI and dementia diagnoses by FPs after 12 months as indicated on a list, was assessed among all persons in whom FPs suspected cognitive impairment but without a formal diagnosis of dementia. The secondary outcome, mental health of patients and their relatives, was assessed among persons consenting to participate in trial stage 2. Trial stage 1 consisted of either intervention component 1: training FPs to diagnose MCI and dementia, or control: no training. Trial stage 2 consisted of either intervention component 2: case finding of MCI and dementia and care by a trained nurse and the FP, or control: care as usual. Results Seven PCPs were randomized to the intervention; eight to the control condition. MCI or dementia was diagnosed in 42.3 (138/326) of persons in the intervention, and in 30.5 (98/321) in the control group (estimated difference GEE: 10.8, OR: 1.51, 95-CI 0.60-3.76). Among patients and relatives who consented to stage 2 of the trial (n = 145; 25), there were no differences in mental health between the intervention and control group. Conclusions We found a non-significant increase in the number of new MCI diagnoses. As we cannot exclude a clinically relevant effect, a larger study is warranted to replicate ours. Trial Registration Nederlands Trial Register NTR3389 © 2016 van den Dungen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Depressive and subthreshold depressive symptomatology among older adults in a socioeconomically deprived area in Brazil

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    Depressive and subthreshold depressive symptomatology are common but often neglected in older adults. / Objective: This study aimed to assess rates of depressive and subthreshold depressive symptomatology, and the characteristics associated, among older adults living in a socioeconomically deprived area of Brazil. / Methods: This study is part of the PROACTIVE cluster randomised controlled trial. 3356 adults aged 60+ years and registered in 20 primary health clinics were screened for depressive symptomatology with the Patient Health Questionnaire-9 (PHQ-9). Depressive status was classified according to the total PHQ-9 score and the presence of core depressive symptoms (depressed mood and anhedonia) as follows: no depressive symptomatology (PHQ-9 score 0–4, or 5–9 but with no core depressive symptom); subthreshold depressive symptomatology (PHQ-9 score 5–9 and at least one core depressive symptom); and depressive symptomatology (PHQ-9 score ≥ 10). Sociodemographic information and self-reported chronic conditions were collected. Relative risk ratios and 95% CIs were obtained using a multinomial regression model. / Results: Depressive and subthreshold depressive symptomatology were present in 30% and 14% of the screened sample. Depressive symptomatology was associated with female gender, low socioeconomic conditions and presence of chronic conditions, whereas subthreshold depressive symptomatology was only associated with female gender and having hypertension. / Conclusions: Depressive and subthreshold depressive symptomatology is highly prevalent in this population registered with primary care clinics. Strategies managed by primary care non-mental health specialists can be a first step for improving this alarming and neglected situation among older adults

    Virtual Resection: A New Tool for Preparing for Nephron-Sparing Surgery in Wilms Tumor Patients

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    Nephron-sparing surgery (NSS) in Wilms tumor (WT) patients is a surgically challenging procedure used in highly selective cases only. Virtual resections can be used for preoperative planning of NSS to estimate the remnant renal volume (RRV) and to virtually mimic radical tumor resection. In this single-center evaluation study, virtual resection for NSS planning and the user experience were evaluated. Virtual resection was performed in nine WT patient cases by two pediatric surgeons and one pediatric urologist. Pre- and postoperative MRI scans were used for 3D visualization. The virtual RRV was acquired after performing virtual resection and a questionnaire was used to assess the ease of use. The actual RRV was derived from the postoperative 3D visualization and compared with the derived virtual RRV. Virtual resection resulted in virtual RRVs that matched nearly perfectly with the actual RRVs. According to the questionnaire, virtual resection appeared to be straightforward and was not considered to be difficult. This study demonstrated the potential of virtual resection as a new planning tool to estimate the RRV after NSS in WT patients. Future research should further evaluate the clinical relevance of virtual resection by relating it to surgical outcome

    The Fundamental Plane and the evolution of the M/L ratio of early-type field galaxies up to z~1

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    We analyse the Fundamental Plane (FP) of 26 strong gravitational lens galaxies with redshifts up to z~1, using tabulated data from Kochanek et al. (2000) and Rusin et al. (2003). The lens galaxies effectively form a mass-selected sample of early-type galaxies in environments of relatively low density. We analyse the FP and its evolution in the restframe Johnson B and Gunn r bands. Assuming that early-type galaxies are a homologous family, the FP then provides a direct measurement of the M/L ratio evolution. If we assume that the M/L ratios of field early-type galaxies evolve as power-laws, we find for the lens galaxies an evolution rate dlog(M/L)/dz of -0.62 +/-0.13 in restframe B, corresponding to a mean stellar formation redshift of =1.8 (-0.5/+1.4). This formation epoch does not differ significantly from that of cluster galaxies =2.0 (-0.2/+0.3), obtained by van Dokkum & Franx (2001) after correction for maximum progenitor bias. However, if we impose the constraint that lens and cluster galaxies that are of the same age have equal M/L ratios and we do not correct for progenitor bias, we find that the stellar populations of the lens galaxies are 10-15 % younger. We find that both the M/L ratios as well as the restframe colors of the lens galaxies show significant scatter. About half of the lens galaxies are consistent with an old cluster-like stellar populations, but the other galaxies are bluer and best fit by single burst models with younger stellar formation redshifts as low as z*~1. Moreover, the scatter in color is correlated with the scatter in M/L ratio. We interpret this as evidence of a significant age spread among the stellar populations of lens galaxies, whereas the ages of the stellar populations of the cluster galaxies are well approximated by a single formation epoch.Comment: 12 pages (5 figures), accepted by MNRAS, abstract abridged; substantial changes from previous version: new data added, color evolution presented (Fig. 4, left), analysis completely in flat cosmology (Omega_M=0.3, Omega_L=0.7

    Uterine bathing with sonography gel prior to IVF/ICSI-treatment in patients with endometriosis, a multicentre randomised controlled trial

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    STUDY QUESTION What is the effect of uterine bathing with sonography gel prior to IVF/ICSI-treatment on live birth rates after fresh embryo transfer in patients with endometriosis? SUMMARY ANSWER After formal interim analysis and premature ending of the trial, no significant difference between uterine bathing using a pharmacologically neutral sonography gel compared to a sham procedure on live birth rate after fresh embryo transfer in endometriosis patients (26.7% vs. 15.4%, relative risk (RR) 1.73, 95% confidence interval (CI) 0.81–3.72; P-value 0.147) could be found, although the trial was underpowered to draw definite conclusions. WHAT IS KNOWN ALREADY Impaired implantation receptivity contributes to reduced clinical pregnancy rates after IVF/ICSI-treatment in endometriosis patients. Previous studies have suggested a favourable effect of tubal flushing with Lipiodol® on natural conceptions. This benefit might also be explained by enhancing implantation through endometrial immunomodulation. Although recent studies showed no beneficial effect of endometrial scratching, the effect of mechanical stress by intrauterine infusion on the endometrium in endometriosis patients undergoing IVF/ICSI-treatment has not been investigated yet. STUDY DESIGN, SIZE, DURATION We performed a multicentre, patient-blinded, randomised controlled trial in which women were randomly allocated to either a Gel Infusion Sonography (GIS, intervention group) or a sham procedure (control group) prior to IVF/ICSI-treatment. Since recruitment was slow and completion of the study was considered unfeasible, the study was halted after inclusion of 112 of the planned 184 women. PARTICIPANTS/MATERIALS, SETTING, METHODS We included infertile women with surgically confirmed endometriosis ASRM stage I–IV undergoing IVF/ICSI-treatment. After informed consent, women were randomised to GIS with intrauterine instillation of ExEm-gel® or sonography with gel into the vagina (sham). This was performed in the cycle preceding the embryo transfer, on the day GnRH analogue treatment was started. The primary endpoint was live birth rate after fresh embryo transfer. Analysis was performed by both intention-to-treat and per-protocol. MAIN RESULTS AND THE ROLE OF CHANCE Between July 2014 to September 2018, we randomly allocated 112 women to GIS (n = 60) or sham procedure (n = 52). The live birth rate after fresh embryo transfer was 16/60 (26.7%) after GIS versus 8/52 (15.4%) after the sham (RR 1.73, 95% CI 0.81–3.72; P-value 0.147). Ongoing pregnancy rate was 16/60 (26.7%) after GIS versus 9/52 (17.3%) in the controls (RR 1.54, 95% CI 0.74–3.18). Miscarriage occurred in 1/60 (1.7%) after GIS versus 5/52 (9.6%) in the controls (RR 0.17, 95% CI 0.02–1.44) women. Uterine bathing resulted in a higher pain score compared with a sham procedure (visual analogue scale score 2.7 [1.3–3.5] vs. 1.0 [0.0–2.0], P < 0.001). There were two adverse events after GIS compared with none after sham procedures. LIMITATIONS, REASONS FOR CAUTION The study was terminated prematurely due to slow recruitment and trial fatigue. Therefore, the trial is underpowered to draw definite conclusions regarding the effect of uterine bathing with sonography gel on live birth rate after fresh embryo transfer in endometriosis patients undergoing IVF/ICSI-treatment. WIDER IMPLICATIONS OF THE FINDINGS We could not demonstrate a favourable effect of uterine bathing procedures with sonography gel prior to IVF/ICSI-treatment in patients with endometriosis. STUDY FUNDING/COMPETING INTEREST(S) Investigator initiated study. IQ Medical Ventures provided the ExEm FOAM® kits free of charge, they were not involved in the study design, data management, statistical analyses and/or manuscript preparation, etc. C.B.L. reports receiving grants from Ferring, Merck and Guerbet, outside the submitted work. C.B.L. is Editor-in-Chief of Human Reproduction. V.M. reports grants and other from Guerbet, outside the submitted work. B.W.M. reports grants from NHMRC (GNT1176437), personal fees from ObsEva, Merck and Merck KGaA, Guerbet and iGenomix, outside the submitted work. N.P.J. reports research funding from Abb-Vie and Myovant Sciences and consultancy for Vifor Pharma, Guerbet, Myovant Sciences and Roche Diagnostics, outside the submitted work. K.D. reports personal fees from Guerbet, outside the submitted work. The other authors do not report any conflicts of interest. No financial support was provided. TRIAL REGISTRATION NUMBER NL4025 (NTR4198) TRIAL REGISTRATION DATE 7 October 2013 DATE OF FIRST PATIENT’S ENROLMENT 22 July 201

    Spectral Action for Robertson-Walker metrics

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    We use the Euler-Maclaurin formula and the Feynman-Kac formula to extend our previous method of computation of the spectral action based on the Poisson summation formula. We show how to compute directly the spectral action for the general case of Robertson-Walker metrics. We check the terms of the expansion up to a_6 against the known universal formulas of Gilkey and compute the expansion up to a_{10} using our direct method

    Diagrams for heat kernel expansions

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    A diagramatic heat kernel expansion technique is presented. The method is especially well suited to the small-derivative expansion of the heat kernel, but it can also be used to reproduce the results obtained by the approach known as covariant perturbation theory. The new technique gives an expansion for the heat kernel at coincident points. It can also be used to obtain the derivative of the heat kernel and this is useful for evaluating the expectation values of the stress-energy tensor.Comment: 17 pages, 4 figures, ReVTe
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