Exploration of Parameter Spaces in a Virtual Observatory

Like every other field of intellectual endeavor, astronomy is being revolutionised by the advances in information technology. There is an ongoing exponential growth in the volume, quality, and complexity of astronomical data sets, mainly through large digital sky surveys and archives. The Virtual Observatory (VO) concept represents a scientific and technological framework needed to cope with this data flood. Systematic exploration of the observable parameter spaces, covered by large digital sky surveys spanning a range of wavelengths, will be one of the primary modes of research with a VO. This is where the truly new discoveries will be made, and new insights be gained about the already known astronomical objects and phenomena. We review some of the methodological challenges posed by the analysis of large and complex data sets expected in the VO-based research. The challenges are driven both by the size and the complexity of the data sets (billions of data vectors in parameter spaces of tens or hundreds of dimensions), by the heterogeneity of the data and measurement errors, including differences in basic survey parameters for the federated data sets (e.g., in the positional accuracy and resolution, wavelength coverage, time baseline, etc.), various selection effects, as well as the intrinsic clustering properties (functional form, topology) of the data distributions in the parameter spaces of observed attributes. Answering these challenges will require substantial collaborative efforts and partnerships between astronomers, computer scientists, and statisticians.Comment: Invited review, 10 pages, Latex file with 4 eps figures, style files included. To appear in Proc. SPIE, v. 4477 (2001

Exploration of Large Digital Sky Surveys

We review some of the scientific opportunities and technical challenges posed by the exploration of the large digital sky surveys, in the context of a Virtual Observatory (VO). The VO paradigm will profoundly change the way observational astronomy is done. Clustering analysis techniques can be used to discover samples of rare, unusual, or even previously unknown types of astronomical objects and phenomena. Exploration of the previously poorly probed portions of the observable parameter space are especially promising. We illustrate some of the possible types of studies with examples drawn from DPOSS; much more complex and interesting applications are forthcoming. Development of the new tools needed for an efficient exploration of these vast data sets requires a synergy between astronomy and information sciences, with great potential returns for both fields.Comment: To appear in: Mining the Sky, eds. A. Banday et al., ESO Astrophysics Symposia, Berlin: Springer Verlag, in press (2001). Latex file, 18 pages, 6 encapsulated postscript figures, style files include

Синтез конденсованих похідних піримідину з використанням NCNCC+C підходу Д.C.Гранат, А.В.Бійцева, О.О.Григоренко, С.В.Рябухін

The methods of synthesis of various substituted fused pyrimidine derivatives using NCNCC+C approach have been systematized and summarized in the review. Approaches based on the reaction of carbonyl compounds with NCNCC binucleophiles, in particular, N-aryl(thio)ureas, derivatives of aniline and aromatic heterocyclic amines, N-arylamidines and N-imidoylphosphoranes have been considered. Although these methods have been known for a long time, recent efforts in this area are put towards development of mild reaction conditions, in particular with the use of chlorotrimethylsilane or microwave irradiation. Besides, palladium-catalyzed cyclizations have been discussed, they involve N-arylamidines or N-arylcarbodiimides as the NCNCC components, and carbon(II) oxide or isocyanides – as single-carbon synthetic equivalents. These methods have received much attention in recent years. Most of them are three-component reactions, which involve an additional nucleophilic reagent; therefore, these approaches have some advantages in the view of diversity of the products obtained. Other methods for NCNCC+C cyclization have been also considered, including reactions of ketimines derived from aminoheterocycles with isocyanates, reactions of N-arylcarbodiimides with molybdenum carbonyl, Cu- and Rh-catalyzed processes, etc. It has been shown that [5+1] cyclization discussed in the review can be used for preparation of fused pyrimidines, which can bear moieties of annelated isoquinolines, thiazoles, pyridines, pyrazines, triazoles, pyrazoles, etc., apart from the simple ring.В обзоре впервые систематизированы и обобщены методы синтеза разнообразных замещенных конденсированных производных пиримидина с использованием NCNCC+C подхода. Рассмотрены методы, основанные на реакции карбонильных соединений с NCNCC бинуклеофилами, в частности, N-арил(тио) мочевинами, производными анилина и ароматических гетероциклических аминов, N-ариламидинами и N-имидоилфосфоранами. Хотя данная группа методов известна относительно давно, значительное количество современных работ в этом направлении посвящено разработке мягких условий проведения реакции, в том числе с использованием триметилхлорсилана или под воздействием микроволнового излучения. Отдельно обсуждены циклизации, катализируемые палладием, в которых в качестве NCNCC компоненты выступают N-ариламидины и N-арилкарбодиимиды, а в качестве С‑составлющей − монооксид углерода или изонитрилы. Эти методы особенно интенсивно развиваются в последние годы и большей частью являются трехкомпонентными реакциями, в которых участие дополнительно принимает нуклеофильный реагент; следовательно, такие процессы обладают рядом преимуществ с точки зрения разнообразия соединений, которые могут быть получены. Рассмотрены также и другие методы, в частности реакции кетиминов на основе аминогетероциклов с изоцианатами, реакции N-арилкарбодиимидов с карбонилом молибдена, Cu- и Rh-катализируемые процессы и т. д. Показано, что [5 +1]-циклизация дает возможность получения различных функционализированных конденсированных пиримидинов, которые, кроме бензольного ядра, могут содержать аннелированные ядра изохинолина, тиазола, пиридина, пиразина, триазола, пиразола и т. п.В огляді вперше систематизовані та узагальнені методи синтезу різноманітних заміщених конденсованих похідних піримідину з використанням NCNCC+C підходу. Розглянуті методи, що базуються на реакції карбонільних сполук з NCNCC бінуклеофілами, зокрема, N-арил(тіо)сечовинами, похідними аніліну та ароматичних гетероциклічних амінів, N-ариламідинами та N-імідоїлфосфоранами. Хоча ця група методів відома відносно давно, значна кількість сучасних робіт у цьому напрямку присвячена розробці м’яких умов проведення реакції, зокрема з використанням триметилхлоросилану або при дії мікрохвильового випромінення. Окремо обговорені Pd-каталізовані циклізації, у яких як NCNCC компоненти виступають N-ариламідини та N-арилкарбодііміди, а як С-складова – карбон(ІІ) оксид або ізонітрили. Ці методи особливо інтенсивно розвиваються в останні роки і найчастіше є трикомпонентними реакціями, в яких додатково бере участь нуклеофільний реагент; отже, такі процеси мають ряд переваг з точки зору різномаїття сполук, які можуть бути одержані. Розглянуті також інші методи, зокрема реакції кетімінів на основі аміногетероциклів з ізоціанатами, реакції N-арилкарбодіімідів з карбонілом молібдену, Cu- та Rh-каталізовані процеси тощо. Показано, що [5+1]-циклізація дає можливість одержання різних функціоналізованих конденсованих піримідинів, які, окрім бензенового ядра, можуть містити анельовані ядра ізохіноліну, тіазолу, піридину, піразину, триазолу, піразолу тощо

Technology for monitoring everyday prosthesis use: a systematic review

BACKGROUND Understanding how prostheses are used in everyday life is central to the design, provision and evaluation of prosthetic devices and associated services. This paper reviews the scientific literature on methodologies and technologies that have been used to assess the daily use of both upper- and lower-limb prostheses. It discusses the types of studies that have been undertaken, the technologies used to monitor physical activity, the benefits of monitoring daily living and the barriers to long-term monitoring. METHODS A systematic literature search was conducted in PubMed, Web of Science, Scopus, CINAHL and EMBASE of studies that monitored the activity of prosthesis-users during daily-living. RESULTS 60 lower-limb studies and 9 upper-limb studies were identified for inclusion in the review. The first studies in the lower-limb field date from the 1990s and the number has increased steadily since the early 2000s. In contrast, the studies in the upper-limb field have only begun to emerge over the past few years. The early lower-limb studies focused on the development or validation of actimeters, algorithms and/or scores for activity classification. However, most of the recent lower-limb studies used activity monitoring to compare prosthetic components. The lower-limb studies mainly used step-counts as their only measure of activity, focusing on the amount of activity, not the type and quality of movements. In comparison, the small number of upper-limb studies were fairly evenly spread between development of algorithms, comparison of everyday activity to clinical scores, and comparison of different prosthesis user populations. Most upper-limb papers reported the degree of symmetry in activity levels between the arm with the prosthesis and the intact arm. CONCLUSIONS Activity monitoring technology used in conjunction with clinical scores and user feedback, offers significant insights into how prostheses are used and whether they meet the user’s requirements. However, the cost, limited battery-life and lack of availability in many countries mean that using sensors to understand the daily use of prostheses and the types of activity being performed has not yet become a feasible standard clinical practice. This review provides recommendations for the research and clinical communities to advance this area for the benefit of prosthesis users

A randomised feasibility study to investigate the impact of education and the addition of prompts on the sedentary behaviour of office workers

Abstract Background Office workers have been identified as being at risk of accumulating high amounts of sedentary time in prolonged events during work hours, which has been associated with increased risk of a number of long-term health conditions. There is some evidence that providing advice to stand at regular intervals during the working day, and using computer-based prompts, can reduce sedentary behaviour in office workers. However, evidence of effectiveness, feasibility and acceptability for these types of intervention is currently limited. Methods A 2-arm, parallel group, cluster-randomised feasibility trial to assess the acceptability of prompts to break up sedentary behaviour was conducted with office workers in a commercial bank (n = 21). Participants were assigned to an education only group (EG) or prompt and education group (PG). Both groups received education on reducing and breaking up sitting at work, and the PG also received hourly prompts, delivered by Microsoft Outlook over 10 weeks, reminding them to stand. Objective measurements of sedentary behaviour were made using activPAL monitors worn at three time points: baseline, in the last 2 weeks of the intervention period and 12 weeks after the intervention. Focus groups were conducted to explore the acceptability of the intervention and the motivations and barriers to changing sedentary behaviour. Results Randomly generated, customised prompts, delivered by Microsoft Outlook, with messages about breaking up sitting, proved to be a feasible and acceptable way of delivering prompts to office workers. Participants in both groups reduced their sitting, but changes were not maintained at follow-up. The education session seemed to increase outcome expectations of the benefits of changing sedentary behaviour and promote self-regulation of behaviour in some participants. However, low self-efficacy and a desire to conform to cultural norms were barriers to changing behaviour. Conclusions Prompts delivered by Microsoft Outlook were a feasible, low-cost way of prompting office workers to break up their sedentary behaviour, although further research is needed to determine whether this has an additional impact on sedentary behaviour, to education alone. The role of cultural norms, and promoting self-efficacy, should be considered in the design of future interventions. Trial registration This study was registered retrospectively as a clinical trial on ClinicalTrials.gov (ID no. NCT02609282 ) on 23 March 2015

The dynamics of nasopharyngeal streptococcus pneumoniae carriage among rural Gambian mother-infant pairs

<p>Abstract</p> <p>Background</p> <p><it>Streptococcus pneumoniae </it>is an important cause of community acquired pneumonia, sepsis, meningitis and otitis media globally and has been incriminated as a major cause of serious childhood bacterial infections in The Gambia. Better understanding of the dynamics of transmission and carriage will inform control strategies.</p> <p>Methods</p> <p>This study was conducted among 196 mother-infant pairs recruited at birth from six villages in the West Kiang region of The Gambia. Nasopharyngeal swabs were collected from mother-infant pairs at birth (within 12 hours of delivery), 2, 5 and 12 months. Standard techniques of culture were used to identify carriage and serotype <it>S. pneumoniae</it>.</p> <p>Results</p> <p>Of 46 serotypes identified, the 6 most common, 6A, 6B, 14, 15, 19F and 23F, accounted for 67.3% of the isolates from infants. Carriage of any serotype among infants rose from 1.5% at birth to plateau at approximately 80% by 2 m (prevalence at 2 m = 77%; 5 m = 86%; 12 m = 78%). Likewise, maternal carriage almost doubled in the first 2 months post-partum and remained elevated for the next 10 m (prevalence at birth = 13%; 2 m = 24%; 5 m = 22%; 12 m = 21%). Carriage was significantly seasonal in both infants and mothers with a peak in December and lowest transmission in August. The total number of different serotypes we isolated from each infant varied and less than would be expected had the serotypes assorted independently. In contrast, this variability was much as expected among mothers. The half-life of a serotype colony was estimated to be 1.90 m (CI_95%: 1.66-2.21) in infants and 0.75 m (CI_95%: 0.55-1.19) in mothers. While the odds for a serotype to be isolated from an infant increased by 9-fold if it had also been isolated from the mother, the population attributable fraction (PAF) of pneumococcal carriage in infants due to maternal carriage was only 9.5%. Some marked differences in dynamics were observed between vaccine and non-vaccine serotypes.</p> <p>Conclusions</p> <p>Colonisation of the nasopharynx in Gambian infants by <it>S. pneumoniae </it>is rapid and highly dynamic. Immunity or inter-serotype competition may play a role in the dynamics. Reducing mother-infant transmission would have a minimal effect on infant carriage.</p

Emerging collaborative research platforms for the next generation of physical activity, sleep and exercise medicine guidelines : the Prospective Physical Activity, Sitting, and Sleep consortium (ProPASS)

Galileo Galilei’s quote “measure what is measurable, and make measurable what is not so” has particular relevance to health behaviours, such as physical activity (PA), sitting and sleep, whose measurement during free living is notoriously difficult. To date, much of what we know about how these behaviours affect our health is based on self-report by questionnaires which have limited validity, are prone to bias, and inquire about selective aspects of these behaviours. Although self-reported evidence has made great contributions to shaping public health and exercise medicine policy and guidelines until now1, the ongoing advancements of accelerometry-based measurement and evidence synthesis methods are set to change the landscape. The aim of this editorial is to outline new directions in PA and sleep related epidemiology that open new horizons for guideline development and improvement; and to describe a new research collaboration platform: the Prospective Physical Activity, Sitting, and Sleep consortium (ProPASS)

Parallel computation of 3-D soil-structure interaction in time domain with a coupled FEM/SBFEM approach

The final publication is available at Springer via http://dx.doi.org/10.1007/s10915-011-9551-xThis paper introduces a parallel algorithm for the scaled boundary finite element method (SBFEM). The application code is designed to run on clusters of computers, and it enables the analysis of large-scale soil-structure-interaction problems, where an unbounded domain has to fulfill the radiation condition for wave propagation to infinity. The main focus of the paper is on the mathematical description and numerical implementation of the SBFEM. In particular, we describe in detail the algorithm to compute the acceleration unit impulse response matrices used in the SBFEM as well as the solvers for the Riccati and Lyapunov equations. Finally, two test cases validate the new code, illustrating the numerical accuracy of the results and the parallel performances. © Springer Science+Business Media, LLC 2011.Jose E. Roman and Enrique S. Quintana-Orti were partially supported by the Spanish Ministerio de Ciencia e Innovacion under grants TIN2009-07519, and TIN2008-06570-C04-01, respectively.Schauer, M.; Román Moltó, JE.; Quintana Orti, ES.; Langer, S. (2012). Parallel computation of 3-D soil-structure interaction in time domain with a coupled FEM/SBFEM approach. Journal of Scientific Computing. 52(2):446-467. doi:10.1007/s10915-011-9551-xS446467522Anderson, E., Bai, Z., Bischof, C., Demmel, J., Dongarra, J., Croz, J.D., Greenbaum, A., Hammarling, S., McKenney, A., Sorensen, D.: LAPACK User’s Guide. Society for Industrial and Applied Mathematics, Philadelphia (1992)Antes, H., Spyrakos, C.: Soil-structure interaction. In: Beskos, D., Anagnotopoulos, S. (eds.) Computer Analysis and Design of Earthquake Resistant Structures, p. 271. Computational Mechanics Publications, Southampton (1997)Appelö, D., Colonius, T.: A high-order super-grid-scale absorbing layer and its application to linear hyperbolic systems. J. Comput. 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Shifting boundaries between the normal and the pathological:the case of mild intellectual disability

When disorders fade into normality, how can the threshold between normality and disorder be determined? In considering mild intellectual disability, I argue that economic factors partly determine thresholds. We tend to assume that the relationship between disorder, need and services is such that: first, a cut-off point between the disordered and the normal is determined; second, a needy population is identified; and third, resources are found (or at least should be found) to meet this need. However, the changing definitions of intellectual disability can best be understood if we think of this happening in reverse. That is, first, certain resources are thought obtainable, and then a cut-off point for disorder is selected which supplies an appropriately sized ‘needy population’

Large Scale Population Assessment of Physical Activity Using Wrist Worn Accelerometers: The UK Biobank Study

BACKGROUND: Physical activity has not been objectively measured in prospective cohorts with sufficiently large numbers to reliably detect associations with multiple health outcomes. Technological advances now make this possible. We describe the methods used to collect and analyse accelerometer measured physical activity in over 100,000 participants of the UK Biobank study, and report variation by age, sex, day, time of day, and season. METHODS: Participants were approached by email to wear a wrist-worn accelerometer for seven days that was posted to them. Physical activity information was extracted from 100Hz raw triaxial acceleration data after calibration, removal of gravity and sensor noise, and identification of wear / non-wear episodes. We report age- and sex-specific wear-time compliance and accelerometer measured physical activity, overall and by hour-of-day, week-weekend day and season. RESULTS: 103,712 datasets were received (44.8% response), with a median wear-time of 6.9 days (IQR:6.5-7.0). 96,600 participants (93.3%) provided valid data for physical activity analyses. Vector magnitude, a proxy for overall physical activity, was 7.5% (2.35mg) lower per decade of age (Cohen's d = 0.9). Women had a higher vector magnitude than men, apart from those aged 45-54yrs. There were major differences in vector magnitude by time of day (d = 0.66). Vector magnitude differences between week and weekend days (d = 0.12 for men, d = 0.09 for women) and between seasons (d = 0.27 for men, d = 0.15 for women) were small. CONCLUSIONS: It is feasible to collect and analyse objective physical activity data in large studies. The summary measure of overall physical activity is lower in older participants and age-related differences in activity are most prominent in the afternoon and evening. This work lays the foundation for studies of physical activity and its health consequences. Our summary variables are part of the UK Biobank dataset and can be used by researchers as exposures, confounding factors or outcome variables in future analyses.The UK Biobank Activity Project and the collection of activity data from participants was funded by the Wellcome Trust (https://wellcome.ac.uk/) and the Medical Research Council (http://www.mrc.ac.uk/). The analysis was supported by the British Heart Foundation Centre of Research Excellence at Oxford (http://www.cardioscience.ox.ac.uk/bhf-centre-of-research-excellence) [grant number RE/13/1/30181 to AD], the Li Ka Shing Foundation (http://www.lksf.org/) [to AD], the UK Medical Research Council (http://www.mrc.ac.uk/) [grant numbers MC_UU_12015/1 and MC_UU_12015/3 to NW and SB], the RCUK Digital Economy Research Hub on Social Inclusion through the Digital Economy (SiDE) (http://www.rcuk.ac.uk/) [EP/G066019/1 to NH], the EPSRC Centre for Doctoral Training in Digital Civics (https://www.epsrc.ac.uk/)[EP/L016176/1 to DJ], and the National Institute for Health Research (http://www.nihr.ac.uk/) [SRF-2011-04-017 to MIT]. The MRC and Wellcome Trust played a key role in the decision to establish UK Biobank, and the accelerometer data collection. No funding bodies had any role in the analysis, decision to publish, or preparation of the manuscript