The CORNISH project is the highest resolution radio continuum survey of the Galactic plane to date. It is the 5 GHz radio continuum part of a series of multi-wavelength surveys that focus on the ...northern GLIMPSE region (10degrees < l < 65degrees), observed by the Spitzer satellite in the mid-infrared. Observations with the Very Large Array in B and BnA configurations have yielded a 1".5 resolution Stokes I map with a root mean square noise level better than 0.4 mJy beam super(-1). Here we describe the data-processing methods and data characteristics, and present a new, uniform catalog of compact radio emission. This includes an implementation of automatic deconvolution that provides much more reliable imaging than standard CLEANing. A rigorous investigation of the noise characteristics and reliability of source detection has been carried out. We show that the survey is optimized to detect emission on size scales up to 14" and for unresolved sources the catalog is more than 90% complete at a flux density of 3.9 mJy. We have detected 3062 sources above a 7sigma detection limit and present their ensemble properties. The catalog is highly reliable away from regions containing poorly sampled extended emission, which comprise less than 2% of the survey area. Imaging problems have been mitigated by down-weighting the shortest spacings and potential artifacts flagged via a rigorous manual inspection with reference to the Spitzer infrared data. We present images of the most common source types found: H II regions, planetary nebulae, and radio galaxies. The CORNISH data and catalog are available online at http://cornish.leeds.ac.uk.
ABSTRACT We describe the motivation, design, and implementation of the CORNISH survey, an arcsecond-resolution radio continuum survey of the inner galactic plane at 5 GHz using the Very Large Array ...(VLA). It is a blind survey coordinated with the northern Spitzer GLIMPSE I region covering 10° < l < 65° and |b| < 1° at similar resolution. We discuss in detail the strategy that we employed to control the shape of the synthesised beam across this survey, which covers a wide range of fairly low declinations. Two snapshots separated by 4h kept the beam elongation to less that 1.5 over 75% of the survey area and less than 2 over 98% of the survey. The prime scientific motivation is to provide an unbiased survey for ultra-compact H II regions to study this key phase in massive star formation. A sensitivity around 2 mJy will allow the automatic distinction between radio-loud and radio-quiet mid-IR sources found in the Spitzer surveys. This survey has many legacy applications beyond star formation, including evolved stars, active stars and binaries, and extragalactic sources. The CORNISH survey for compact ionized sources complements other Galactic plane surveys that target diffuse and nonthermal sources, as well as atomic and molecular phases to build up a complete picture of the interstellar medium in the Galaxy.
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ObjectivesLocally led health research in low and middle income countries (LMICs) is critical for overcoming global health challenges. Yet, despite over 25 years of international efforts, health ...research capacity in LMICs remains insufficient and development attempts continue to be fragmented. The aim of this systematic review is to identify and critically examine the main approaches and trends in health research capacity development and consolidate key thinking to identify a more coherent approach.MethodsThis review includes academic and grey literature published between January 2000 and July 2013. Using a predetermined search strategy, we systematically searched PubMed, hand-searched Google Scholar and checked reference lists. This process yielded 1668 papers. 240 papers were selected based on a priori criteria. A modified version of meta-narrative synthesis was used to analyse the papers.Results3 key narratives were identified: the effect of power relations on capacity development; demand for stronger links between research, policy and practice and the importance of a systems approach. Capacity development was delivered through 4 main modalities: vertical research projects, centres of excellence, North–South partnerships and networks; all were controversial, and each had their strengths and weaknesses. A plurality of development strategies was employed to address specific barriers to health research. However, lack of empirical research and monitoring and evaluation meant that their effectiveness was unclear and learning was weak.ConclusionsThere has been steady progress in LMIC health research capacity, but major barriers to research persist and more empirical evidence on development strategies is required. Despite an evolution in development thinking, international actors continue to use outdated development models that are recognised as ineffective. To realise newer development thinking, research capacity outcomes need to be equally valued as research outputs. While some development actors are now adopting this dedicated capacity development approach, they are in the minority.
Optimal Cooperative Sensing using a Team of UAVs Gu, G.; Chandler, P.R.; Schumacher, C.J. ...
IEEE transactions on aerospace and electronic systems,
10/2006, Volume:
42, Issue:
4
Journal Article
Peer reviewed
The authors investigates the joint optimal estimation of both the position and velocity of a ground moving target (GMT) using pulse Doppler radars on-board unmanned aerial vehicles (UAVs). The ...problem of cooperative estimation using a UAV team and the optimization of the team's configuration to achieve optimal GMT position and velocity estimates are addressed. Based on the Cramer-Rao bound, the minimum achievable error variance of the GMT position and velocity estimates is derived. The expression of the minimum achievable estimation error variance for unbiased estimation provided by the Cramer-Rao bound is minimized yielding the optimal configuration of the UAV team. Our solution is complete in that it addresses various GMT tracking scenarios and an arbitrary number of UAVs. Optimal sensor geometries for typical applications are illustrated
ObjectivesIn 2013, the WHO stated that unless low-income and middle-income countries (LMICs) become producers of research, health goals would be hard to achieve. Among the capacities required to ...build a local evidence base, ability to conduct clinical trials is important. There is no evidence-based guidance for the best ways to develop locally led trial capacity. This research aims to identify the barriers and enablers to locally led clinical trial conduct in LMICs and determine strategies for their sustainable development.DesignProspective, multiple case study design consisting of interviews (n=34), focus group discussions (n=13) and process mapping exercises (n=10).SettingCase studies took place in Ethiopia (2011), Cameroon (2012) and Sri Lanka (2013).ParticipantsLocal health researchers with previous experiences of clinical trials or stakeholders with an interest in trials were purposively selected through registration searches and snowball sampling (n=100).Primary and secondary outcome measuresDiscussion notes and transcripts were analysed using thematic coding analysis. Key themes and mechanisms were identified.ResultsInstitutions and individuals were variably successful at conducting trials, but there were strong commonalities in the barriers and enablers across all levels and functions of the research systems. Transferable mechanisms were summarised into the necessary conditions for trial undertaking, which included: awareness of research, motivation, knowledge and technical skills, leadership capabilities, forming collaborations, inclusive trial operations, policy relevance and uptake and macro and institutional strengthening.ConclusionsBarriers and enablers to locally led trial undertaking exist at all levels and functions of LMIC research systems. Establishing the necessary conditions to facilitate this research will require multiple, coordinated interventions that seek to resolve them in a systemic manner. The strategies presented in the discussion provide an evidence-based framework for a self-sustaining capacity development approach. This represents an important contribution to the literature that will be relevant for research funders, users and producers.
The problem of providing surgical navigation using image overlays on the operative scene can be split into four main tasks-calibration of the optical system; registration of preoperative images to ...the patient; system and patient tracking, and display using a suitable visualization scheme. To achieve a convincing result in the magnified microscope view a very high alignment accuracy is required. The authors have simulated an entire image overlay system to establish the most significant sources of error and improved each of the stages involved. The microscope calibration process has been automated. The authors have introduced bone-implanted markers for registration and incorporated a locking acrylic dental stent (LADS) for patient tracking. The LADS can also provide a less-invasive registration device with mean target error of 0.7 mm in volunteer experiments. These improvements have significantly increased the alignment accuracy of the authors' overlays. Phantom accuracy is 0.3-0.5 mm and clinical overlay errors were 0.5-1.0 mm on the bone fiducials and 0.5-4 mm on target structures. The authors have improved the graphical representation of the stereo overlays. The resulting system provides three-dimensional surgical navigation for microscope-issisted guided interventions (MAGI).
Background: Alcohol ingestion is associated with an increased risk of breast cancer in most epidemiologic studies. Results, however, are heterogeneous at lower levels of alcohol intake, and a ...biologic mechanism for the association has not been clearly identified. To determine whether alcohol consumption by postmenopausal women elevates serum levels of hormones associated with an increased risk of breast cancer, we performed a controlled feeding study. Methods: Participants were 51 healthy postmenopausal women not using hormone replacement therapy. Each participant rotated through three 8-week dietary periods in which she consumed 15 or 30 g of alcohol per day or an alcohol-free placebo beverage. The order of assignment to the three alcohol levels was random. During the dietary periods, all food and beverages were supplied by the study, and energy intake was adjusted to keep body weight constant. Levels of estradiol, estrone, estrone sulfate, testosterone, androstenedione, progesterone, dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), and androstenediol were measured by radioimmunoassays in serum collected at the end of each dietary period. All statistical tests are two-sided. Results: When women consumed 15 or 30 g of alcohol per day, respectively, estrone sulfate concentrations increased by 7.5% (95% confidence interval CI = −0.3% to 15.9%; P = .06) and 10.7% (95% CI = 2.7% to 19.3%; P = .009) and DHEAS concentrations increased by 5.1% (95% CI = 1.4% to 9.0%; P = .008) and 7.5% (95% CI = 3.7% to 11.5%; P<.001) relative to levels when women consumed placebo. None of the other hormones measured changed statistically significantly when women consumed alcohol. Conclusions: Results suggest a possible mechanism by which consumption of one or two alcoholic drinks per day by postmenopausal women could increase their risk of breast cancer.
A comprehensive hydroclimatic data set is presented for the 2011 water year to improve understanding of hydrologic processes in the rain-snow transition zone. This type of data set is extremely rare ...in scientific literature because of the quality and quantity of soil depth, soil texture, soil moisture, and soil temperature data. Standard meteorological and snow cover data for the entire 2011 water year are included, which include several rain-on-snow (ROS) events. Surface soil textures and soil depths from 57 points are presented as well as soil texture profiles from 14 points. Meteorological data include continuous hourly shielded, unshielded, and wind-corrected precipitation, wind speed and direction, air temperature, relative humidity, dew point temperature, and incoming solar and thermal radiation data. This data is often viewed as "forcing data", and is gap filled and serially complete. Sub-surface data included are hourly soil moisture data from multiple depths from seven soil profiles within the catchment, and soil temperatures from multiple depths from two soil profiles. Hydrologic response data include hourly stream discharge from the catchment outlet weir, continuous snow depths from one location, intermittent snow depths from 5 locations, and snow depth and density data from ten weekly snow surveys. Snow and hydrologic response data are meant to provide data on the catchment hydrologic response to the weather data. This data is mostly presented "as measured" although snow depths from one sensor and streamflow at the catchment outlet have been gap filled and are serially complete. Though the weather, snow, and hydrologic response data only covers one water year, the presentation of the additional subsurface data (soil depth, texture, moisture, and temperature) makes it one of the most detailed and complete hydro-climatic data sets from the climatically sensitive rain-snow transition zone. The data presented are appropriate for a wide range of modeling (energy balance snow modeling, soil capacitance parametric modeling, etc.) and descriptive studies. Data is available at doi:10.1594/PANGAEA.819837.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Highlights • Influence of load rate shown for biogalvanic characterisation of ex vivo tissue. • A time-dependent biogalvanic characterisation model has been developed. • Application of this model ...reduces the influence of external load switching rate. • Tissue health discrimination has been demonstrated using the proposed model. • The proposed model improves the applicability of biogalvanic method to surgery.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK