Comparison of LISA and Atom Interferometry for Gravitational Wave Astronomy in Space

One of the atom interferometer gravitational wave missions proposed by Dimopoulos et al.1 in 2008 was called AGIS-Sat. 2. It had a suggested gravitational wave sensitivity set by the atom state detection shot noise level that started at 1 mHz, was comparable to LISA sensitivity from 1 to about 20 mHz, and had better sensitivity from 20 to 500 mHz. The separation between the spacecraft was 1,000 km, with atom interferometers 200 m long and shades from sunlight used at each end. A careful analysis of many error sources was included, but requirements on the time-stability of both the laser wavefront aberrations and the atom temperatures in the atom clouds were not investigated. After including these considerations, the laser wavefront aberration stability requirement to meet the quoted sensitivity level is about 1\times10-8 wavelengths, and is far tighter than for LISA. Also, the temperature fluctuations between atom clouds have to be less than 1 pK. An alternate atom interferometer GW mission in Earth orbit called AGIS-LEO with 30 km satellite separation has been suggested recently. The reduction of wavefront aberration noise by sending the laser beam through a high-finesse mode-scrubbing optical cavity is discussed briefly, but the requirements on such a cavity are not given. Unfortunately, such an Earth-orbiting mission seems to be considerably more difficult to design than a non-geocentric mission and does not appear to have comparably attractive scientific goals.Comment: Submitted to Proc. 46th Rencontres de Moriond: Gravitational Waves and Experimental Gravity, March 20 - 27, 2011, La Thuile, Ital

A set of pedagogical recommendations for improving the integrated approach to childhood overweight and obesity: A Delphi study

Background: Tackling the increasing global problem of childhood overweight and obesity requires an integrated approach. Studies increasingly emphasize the importance of the parents' role in interventions designed to prevent overweight in children. The aim of this study was to develop a unified set of recommendations for healthy parenting practices that can be applied by all professionals who work with children age 4-13 years and can contribute to strengthening the integrated approach to childhood overweight. Methods: A modified Delphi procedure was used to reach consensus regarding what these pedagogical recommendations should encompass. The 30 panelists were professionals and researchers who work with children age 4-13 in the domains of health care, overweight, parenting, education, nutrition, and/or sports. The procedure consisted of: i) extracting existing pedagogical recommendations from national guidelines and professional protocols, ii) appraising and prioritizing these recommendations in terms of relevance through two rounds of questionnaires, and iii) meeting to discuss and approve the set of recommendations. Results: Consensus was reached for one set of eleven pedagogical theme-based recommendations designed to support and instruct parents how to stimulate healthy energy balance-related behaviors in their child. Each recommendation contained information regarding: i) which behaviors in the child and/or parent are important, ii) why this is important, and iii) how parents can stimulate this behavior by applying parenting skills in daily life. The eleven themes were: modeling, positive parenting, breakfast, varied diet, sugar-sweetened beverages, snacks, physical activity, playing sports, quantity of screen time, screen time during meals, and sleep. Conclusion We developed a set of recommendations for healthy parenting that can be used by various professionals working with children age 4-13 and can contribute to creating an integrated approach to childhood overweight. We also developed a web-based app called “Recommendations for Healthy Parenting” as a convenient tool for following these recommendations

The effectiveness of a web-based Dutch parenting program to prevent overweight in children 9–13 years of age:Results of a two-armed cluster randomized controlled trial

INTRODUCTION: Although parental support is an important component in programs designed to prevent overweight in children, current programs pay remarkably little attention to the role of parenting. We therefore developed a web-based parenting program entitled “Making a healthy deal with your child”. This e-learning program can be incorporated into existing overweight prevention programs. The aim of this study was to determine the effectiveness of this e-learning program. MATERIALS AND METHODS: The effectiveness was examined in a two-armed cluster randomized controlled trial. The participants were 475 parent-child dyads of children 9–13 years of age in the Netherlands who participated in an existing schoolclass-based overweight prevention program. At the school grade level, parents were randomly assigned to either the intervention or the control condition. Measurements were taken from both parents and children at baseline, and 5 and 12 months after baseline. Primary outcomes included the child’s dietary and sedentary behavior, and level of physical activity. Secondary outcomes included general parenting style, specific parenting practices, and parental self-efficacy. Linear mixed effects models and generalized linear mixed effects models were conducted in R. RESULTS: Intention-to-treat analyses and completers only revealed no significant effects between the intervention and control condition on energy balance-related behaviors of the child and parenting skills after correction for multiple testing. The parents’ mean satisfaction with the e-learning program (on a 10-point scale) was 7.0±1.1. CONCLUSIONS: Although parents were generally satisfied with the parenting program, following this program had no significant beneficial effects regarding the children’s energy balance-related behaviors or the parenting skills compared to the control condition. This program may be more beneficial if used by high-risk groups (e.g. parents of children with unhealthy energy balance-related behaviors and/or with overweight) compared to the general population, warranting further study

Life support functies van de bodem: operationalisering t.b.v. het biodiversiteitsbeleid

Ter uitvoering van actiepunt NMW1a uit het Strategisch Plan van Aanpak biodiversiteit (SPA; LNV, VROM, V&W, OCW, EZ, BZ, 1995) en als onderdeel van actie N59 uit het NMP-2, is eerder een studie uitgevoerd naar de mogelijkheden om een indicatorsysteem op te stellen voor biodiversiteit van de bodem in relatie tot Life support functies (LSF). In een pilotproject is het indicatorsysteem vervolgens getest binnen de infrastructuur van het Landelijk Meetnet Bodemkwaliteit (LMB). Het indicatorsysteem, en de daaruit af te leiden bodembiologische indicator, bestaat uit een aantal deelindicatoren. De vragen van het onderzoek waren.- kan de gekozen indicatorset worden toegepast in een meetnet; hebben de deelindicatoren van de set voldoende onderscheidend vermogen; kunnen de resultaten worden ingepast in de huidige diagnostische en prognostische gereedschappen van het RIVM (Natuurplanner en EKI).De resultaten en conclusies uit de pilot zijn in dit beleidsgerichte rapport kort beschreven. Een meer gedetailleerde uitwerking van de onderzoeksresultaten verschijnt in het achtergrond-rapport. De pilot heeft aangetoond dat de geselecteerde deelindicatoren gevoelig en onderscheidend zijn voor verschillende combinaties van bodemtype en landgebruik. Als een mogelijke vorm voor het weergeven van de resultaten behaald met de bodembiologische indicator, is een AMOEBE gemaakt voor graslanden op zeeklei. Hierbij is gebruik gemaakt van een gekozen (voorlopige) referentie. De gegevens zijn verder geaggregeerd tot een Bodemkwaliteitsindex (BKX). Op deze wijze zou aan een ecologische bodembeoordeling vorm gegeven kunnen worden. Door systematisch onderzoek aan LSF-deelindicatoren in het Landelijk Meetnet Bodemkwaliteit (40 locaties per jaar) kan in 5 jaar een database opgebouwd worden waarmee responsrelaties voor bodemeigenschappen, systeemeigen- en systeemvreemde stoffen zijn af te leiden. Hiermee kan een LSF-module (prognostisch instrument) worden opgenomen in een decision support systeem als de Natuurplanne

A framework for modelling the biomechanical behaviour of the human liver during breathing in real time using machine learning

Progress in biomechanical modelling of human soft tissue is the basis for the development of new clinical applications capable of improving the diagnosis and treatment of some diseases (e.g. cancer), as well as the surgical planning and guidance of some interventions. The finite element method (FEM) is one of the most popular techniques used to predict the deformation of the human soft tissue due to its high accuracy. However, FEM has an associated high computational cost, which makes it difficult its integration in real-time computer-aided surgery systems. An alternative for simulating the mechanical behaviour of human organs in real time comes from the use of machine learning (ML) techniques, which are much faster than FEM. This paper assesses the feasibility of ML methods for modelling the biomechanical behaviour of the human liver during the breathing process, which is crucial for guiding surgeons during interventions where it is critical to track this deformation (e.g. some specific kind of biopsies) or for the accurate application of radiotherapy dose to liver tumours. For this purpose, different ML regression models were investigated, including three tree-based methods (decision trees, random forests and extremely randomised trees) and other two simpler regression techniques (dummy model and linear regression). In order to build and validate the ML models, a labelled data set was constructed from modelling the deformation of eight ex-vivo human livers using FEM. The best prediction performance was obtained using extremely randomised trees, with a mean error of 0.07 mm and all the samples with an error under 1 mm. The achieved results lay the foundation for the future development of some real-time software capable of simulating the human liver deformation during the breathing process during clinical interventions.This work has been funded by the Spanish Ministry of Economy and Competitiveness (MINECO) through research projects TIN2014-52033-R and DPI2013-40859-R, both also supported by European FEDER funds. The authors acknowledge the kind collaboration of the personnel from the hospital involved in the research.Lorente, D.; Martínez-Martínez, F.; Rupérez Moreno, MJ.; Lago, MA.; Martínez-Sober, M.; Escandell-Montero, P.; Martínez-Martínez, JM.... (2017). A framework for modelling the biomechanical behaviour of the human liver during breathing in real time using machine learning. Expert Systems with Applications. 71:342-357. doi:10.1016/j.eswa.2016.11.037S3423577

Sub-arcsecond imaging with the International LOFAR Telescope I. Foundational calibration strategy and pipeline

The International LOFAR Telescope is an interferometer with stations spread across Europe. With baselines of up to ~2000 km, LOFAR has the unique capability of achieving sub-arcsecond resolution at frequencies below 200 MHz. However, it is technically and logistically challenging to process LOFAR data at this resolution. To date only a handful of publications have exploited this capability. Here we present a calibration strategy that builds on previous high-resolution work with LOFAR. It is implemented in a pipeline using mostly dedicated LOFAR software tools and the same processing framework as the LOFAR Two-metre Sky Survey (LoTSS). We give an overview of the calibration strategy and discuss the special challenges inherent to enacting high-resolution imaging with LOFAR, and describe the pipeline, which is publicly available, in detail. We demonstrate the calibration strategy by using the pipeline on P205+55, a typical LoTSS pointing with an 8 h observation and 13 international stations. We perform in-field delay calibration, solution referencing to other calibrators in the field, self-calibration of these calibrators, and imaging of example directions of interest in the field. We find that for this specific field and these ionospheric conditions, dispersive delay solutions can be transferred between calibrators up to ~1.5° away, while phase solution transferral works well over ~1°. We also demonstrate a check of the astrometry and flux density scale with the in-field delay calibrator source. Imaging in 17 directions, we find the restoring beam is typically ~0.3′′ ×0.2′′ although this varies slightly over the entire 5 deg2 field of view. We find we can achieve ~80–300 μJy bm−1 image rms noise, which is dependent on the distance from the phase centre; typical values are ~90 μJy bm−1 for the 8 h observation with 48 MHz of bandwidth. Seventy percent of processed sources are detected, and from this we estimate that we should be able to image roughly 900 sources per LoTSS pointing. This equates to ~ 3 million sources in the northern sky, which LoTSS will entirely cover in the next several years. Future optimisation of the calibration strategy for efficient post-processing of LoTSS at high resolution makes this estimate a lower limit

Models for Type Ia supernovae and related astrophysical transients

We give an overview of recent efforts to model Type Ia supernovae and related astrophysical transients resulting from thermonuclear explosions in white dwarfs. In particular we point out the challenges resulting from the multi-physics multi-scale nature of the problem and discuss possible numerical approaches to meet them in hydrodynamical explosion simulations and radiative transfer modeling. We give examples of how these methods are applied to several explosion scenarios that have been proposed to explain distinct subsets or, in some cases, the majority of the observed events. In case we comment on some of the successes and shortcoming of these scenarios and highlight important outstanding issues.Comment: 20 pages, 2 figures, review published in Space Science Reviews as part of the topical collection on supernovae, replacement corrects typos in the conclusions sectio

Astronomical Distance Determination in the Space Age: Secondary Distance Indicators

The formal division of the distance indicators into primary and secondary leads to difficulties in description of methods which can actually be used in two ways: with, and without the support of the other methods for scaling. Thus instead of concentrating on the scaling requirement we concentrate on all methods of distance determination to extragalactic sources which are designated, at least formally, to use for individual sources. Among those, the Supernovae Ia is clearly the leader due to its enormous success in determination of the expansion rate of the Universe. However, new methods are rapidly developing, and there is also a progress in more traditional methods. We give a general overview of the methods but we mostly concentrate on the most recent developments in each field, and future expectations. © 2018, The Author(s)

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362