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Registry-based trials have emerged as a potentially cost-saving study methodology. Early estimates of cost savings, however, conflated the benefits associated with registry utilisation and those associated with other aspects of pragmatic trial designs, which might not all be as broadly applicable. In this study, we sought to build a practical tool that investigators could use across disciplines to estimate the ranges of potential cost differences associated with implementing registry-based trials versus standard clinical trials.
We built simulation Markov models to compare unique costs associated with data acquisition, cleaning, and linkage under a registry-based trial design versus a standard clinical trial. We conducted one-way, two-way, and probabilistic sensitivity analyses, varying study characteristics over broad ranges, to determine thresholds at which investigators might optimally select each trial design.
Registry-based trials were more cost effective than standard clinical trials 98.6% of the time. Data-related cost savings ranged from $4300 to $600,000 with variation in study characteristics. Cost differences were most reactive to the number of patients in a study, the number of data elements per patient available in a registry, and the speed with which research coordinators could manually abstract data. Registry incorporation resulted in cost savings when as few as 3768 independent data elements were available and when manual data abstraction took as little as 3.4 seconds per data field.
Registries offer important resources for investigators. When available, their broad incorporation may help the scientific community reduce the costs of clinical investigation. We offer here a practical tool for investigators to assess potential costs savings.
A new deep level transient spectroscopy (DLTS) technique is described, called half-width at variable intensity analysis. This method utilizes the width and normalized intensity of a DLTS signal to determine the activation energy and capture cross section of the trap that generated the signal via a variable, kO. This constant relates the carrier emission rates giving rise to the differential capacitance signal associated with a given trap at two different temperatures: the temperature at which the maximum differential capacitance is detected, and an arbitrary temperature at which some nonzero differential capacitance signal is detected. The extracted activation energy of the detected trap center is used along with the position of the peak maximum to extract the capture cross section of the trap center.
Specific demand of lightweight and high efficient flexible energy unit is increased day by day for its integration into bendable electronics devices. Super-capacitor is one of the promising power unit to meet the current requirement. Flexible metal oxide and polypyrrole based flexible electrode materials are prepared using electrodeposition. The calculated specific capacitances of the devices shows 0.5 mill farad per gram. The super-capacitor is ultra-flexible, stable with operational voltage window expands from 0.8 to 2.5 V which can help to reduce the number of super-capacitor in series connection to obtain the same output. In this study, a conductive polymer can be coupled with MnO2 to improve capacitance and conductivity of a hybrid structure based on MnO2.
Graduate students are often plagued by stress and anxiety in their journeys of becoming researchers. Concerned by the prevalence of poor graduate student wellbeing in Australia, we share our experiences of kin-making and collaboration within #aaeeer (Australasian Association for Environmental Education Emerging Researchers), a collective of graduate students and early career researchers formed in response to the Australian Association for Environmental Education (AAEE) conference in Hobart, Tasmania, in 2014. In this article, we begin to address the shortage of research into graduate student wellbeing, led by graduate students. Inspired by Donna Haraway's work on making kin in the Chthulucene, we present an exploration that draws together stories from the authors about the positive experiences our kin-making collective enables, and how it has supported our wellbeing and allowed us to work collaboratively. Specifically, we find that #aaeeer offers us a form of refuge from academic stressors, creating spaces for ‘composting together’ through processes of ‘decomposing’ and ‘recomposing’. Our rejection of neoliberal norms has gifted us experiences of joyful collective pleasures. We share our experiences here in the hope of supporting and inspiring other emerging and established researchers to ‘make kin’ and challenge the potentially isolating processes of becoming researchers.
The Taipan galaxy survey (hereafter simply ‘Taipan’) is a multi-object spectroscopic survey starting in 2017 that will cover 2π steradians over the southern sky (δ ≲ 10°, |b| ≳ 10°), and obtain optical spectra for about two million galaxies out to z < 0.4. Taipan will use the newly refurbished 1.2-m UK Schmidt Telescope at Siding Spring Observatory with the new TAIPAN instrument, which includes an innovative ‘Starbugs’ positioning system capable of rapidly and simultaneously deploying up to 150 spectroscopic fibres (and up to 300 with a proposed upgrade) over the 6° diameter focal plane, and a purpose-built spectrograph operating in the range from 370 to 870 nm with resolving power R ≳ 2000. The main scientific goals of Taipan are (i) to measure the distance scale of the Universe (primarily governed by the local expansion rate, H0) to 1% precision, and the growth rate of structure to 5%; (ii) to make the most extensive map yet constructed of the total mass distribution and motions in the local Universe, using peculiar velocities based on improved Fundamental Plane distances, which will enable sensitive tests of gravitational physics; and (iii) to deliver a legacy sample of low-redshift galaxies as a unique laboratory for studying galaxy evolution as a function of dark matter halo and stellar mass and environment. The final survey, which will be completed within 5 yrs, will consist of a complete magnitude-limited sample (i ⩽ 17) of about 1.2 × 106 galaxies supplemented by an extension to higher redshifts and fainter magnitudes (i ⩽ 18.1) of a luminous red galaxy sample of about 0.8 × 106 galaxies. Observations and data processing will be carried out remotely and in a fully automated way, using a purpose-built automated ‘virtual observer’ software and an automated data reduction pipeline. The Taipan survey is deliberately designed to maximise its legacy value by complementing and enhancing current and planned surveys of the southern sky at wavelengths from the optical to the radio; it will become the primary redshift and optical spectroscopic reference catalogue for the local extragalactic Universe in the southern sky for the coming decade.
OBJECTIVES/SPECIFIC AIMS: To create a searchable public registry of all Quality Improvement (QI) projects. To incentivize the medical professionals at UF Health to initiate quality improvement projects by reducing startup burden and providing a path to publishing results. To reduce the review effort performed by the internal review board on projects that are quality improvement Versus research. To foster publication of completed quality improvement projects. To assist the UF Health Sebastian Ferrero Office of Clinical Quality & Patient Safety in managing quality improvement across the hospital system. METHODS/STUDY POPULATION: This project used a variant of the spiral software development model and principles from the ADDIE instructional design process for the creation of a registry that is web based. To understand the current registration process and management of quality projects in the UF Health system a needs assessment was performed with the UF Health Sebastian Ferrero Office of Clinical Quality & Patient Safety to gather project requirements. Biweekly meetings were held between the Quality Improvement office and the Clinical and Translational Science – Informatics and Technology teams during the entire project. Our primary goal was to collect just enough information to answer the basic questions of who is doing which QI project, what department are they from, what are the most basic details about the type of project and who is involved. We also wanted to create incentive in the user group to try to find an existing project to join or to commit the details of their proposed new project to a data registry for others to find to reduce the amount of duplicate QI projects. We created a series of design templates for further customization and feature discovery. We then proceed with the development of the registry using a Python web development framework called Django, which is a technology that powers Pinterest and the Washington Post Web sites. The application is broken down into 2 main components (i) data input, where information is collected from clinical staff, Nurses, Pharmacists, Residents, and Doctors on what quality improvement projects they intend to complete and (ii) project registry, where completed or “registered” projects can be viewed and searched publicly. The registry consists of a quality investigator profile that lists contact information, expertise, and areas of interest. A dashboard allows for the creation and review of quality improvement projects. A search function enables certain quality project details to be publicly accessible to encourage collaboration. We developed the Registry Matching Algorithm which is based on the Jaccard similarity coefficient that uses quality project features to find similar quality projects. The algorithm allows for quality investigators to find existing or previous quality improvement projects to encourage collaboration and to reduce repeat projects. We also developed the QIPR Approver Algorithm that guides the investigator through a series of questions that allows an appropriate quality project to get approved to start without the need for human intervention. RESULTS/ANTICIPATED RESULTS: A product of this project is an open source software package that is freely available on GitHub for distribution to other health systems under the Apache 2.0 open source license. Adoption of the Quality Improvement Project Registry and promotion of it to the intended audience are important factors for the success of this registry. Thanks goes to the UW-Madison and their QI/Program Evaluation Self-Certification Tool (https://uwmadison.co1.qualtrics.com/SE/?SID=SV_3lVeNuKe8FhKc73) used as example and inspiration for this project. DISCUSSION/SIGNIFICANCE OF IMPACT: This registry was created to help understand the impact of improved management of quality projects in a hospital system. The ultimate result will be to reduce time to approve quality improvement projects, increase collaboration across the UF Health Hospital system, reduce redundancy of quality improvement projects and translate more projects into publications.
To evaluate invasiveness index as a potential predictor of spine surgical site infection (SSI) after spinal fusion, revision fusion, or laminectomy.
Retrospective cohort study.
Single, large, academic medical center.
Adults undergoing spinal fusion, revision fusion, or laminectomy.
Data were obtained from electronic hospital databases; cases of SSI were extracted from the infection control database using National Healthcare Safety Network (NHSN) definitions. For each case, an invasiveness index, determined by surgical approach, procedure, and number of spine levels treated, was calculated using current procedural terminology (CPT) billing codes. Statistical analyses were performed using univariate and multivariate logistic regression models.
In total, 3,143 patients met inclusion criteria, and 43 of these developed SSI. Multivariate regression showed that advanced age (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.005–1.05, for each year of life) and invasiveness index (medium invasiveness index OR, 5.36; 95% CI, 1.92–14.96; high invasiveness index OR, 14.1; 95% CI, 4.38–45.43) were significant predictors of infection. In subgroup analyses of spinal fusion patients, morbid obesity (OR, 2.542; 95% CI, 1.08–5.99), trauma (OR, 2.41; 95% CI, 1.05–5.55), and invasiveness index (medium invasiveness index OR, 5.39; 95% CI, 1.56–18.61; high invasiveness index OR, 13.44; 95% CI, 3.28–55.01) were significant predictors of SSI. Models containing invasiveness index were compared to NHSN models and demonstrated similar performance.
Invasiveness index is a predictor of SSI after spinal fusion and performs similarly to NHSN models. Invasiveness index shows promise as a potential risk stratification tool that is easily calculated and is available preoperatively.
Many patients with suspected scaphoid fractures but negative radiographs are immobilized for ≥ 2 weeks and are eventually found to have no fracture. Bone scans are reportedly 99% sensitive for these injuries if done ≥ 72 hours postinjury.
The purpose of this study was to determine if early bone scans would allow for shorter cast immobilization periods in patients with suspected scaphoid fractures.
Twenty-seven patients with clinically suspected scaphoid fractures and negative radiographs were randomized to early diagnosis (bone scan within 3–5 days; n 5 12) or traditional diagnosis (radiographs 10–14 days postinjury; n 5 15). The primary outcome was number of days immobilized in a cast.
The mean number of days immobilized was 26 in the traditional group and 29 in the bone scan group. Overall, 6 patients had scaphoid fractures (2 in the traditional diagnosis group and 4 in the bone scan group; p > 0.05), and 8 had other types of fractures. These other types of fractures included four distal radius fractures, two triquetral fractures, one trapezoid fracture, and one hamate fracture. There was no significant difference in the number of other types of fractures between groups. The Kaplan-Meier survival analysis using the log-rank test revealed that there was no statistically significant difference between days immobilized between the radiograph and bone scan groups (p 5 0.38).
The current study suggests that the use of bone scans to help diagnose occult scaphoid fractures does not reduce the number of days immobilized and that the differential diagnosis of occult scaphoid fractures should remain broad because other injuries are common.
Without doubt happiness is the central concept on which ancient moral philosophy was found. Christian authors' approach to philosophy is very much shaped by their understanding of happiness. The author first sketches out the basic characteristics of Aristotelian happiness. Afterwards, he briefly examines Albert the Great's commentaries on the EN. Aquinas's interpretation of Aristotelian happiness in his own commentary, the Sententia Libri Ethicorum(SLE), can be understood at least partly as a critical reaction to the highly influential reading of his teacher. The author outlines Aquinas's understanding of happiness, starting from his commentary and proceeding to the theological works. This enable to finally evaluate the way in which Aquinas's theological background shaped his reading of Aristotelian eudaimonia. Aristotle generally sticks to the idea that virtuous activity is the essential and constitutive part of happiness.
We prepared hybrid aluminum oxide (Al2O3)/polymethyl methacrylate (PMMA) composites with tunable lamellae, produced through a two-step synthetic method: fabrication of inorganic scaffolds via ice-templating, followed by organic infiltration polymerization as a substitute for the sublimed ice. The final lamellar hybrid products show anisotropic physical properties. The thermal conductivity in both principal directions was determined for three different samples as a function of temperature (∼3 K–300 K). Typical room temperature thermal conductivities are in the range of 0.5–2.5 W/(m K), depending on the composition and direction. Across the lamellae, the thermal conductivity is well modeled by a linear series of thermal resistors, and along the lamellae it is well represented by parallel thermal resistors of continuous slabs of PMMA and ∼200-μm long slabs of Al2O3, joined by PMMA. From the thermal conductivity perspective, the Al2O3/PMMA composite is a nacre mimic.
To compare North American Symptomatic Carotid Endarterectomy Trial (NASCET) stenosis values and NASCET grade categorization (mild, moderate, severe) of semi-automated vessel analysis software versus manual measurements on computed tomography angiography (CTA).
There were four observers. Two independently analyzed 81 carotid artery CTAs using semi-automated vessel analysis software according to a blinded protocol. The software measured the narrowest stenosis in millimeters (mm), distal internal carotid artery (ICA) in mm, and calculated percent stenosis based on NASCET criteria. One of these two observers performed this task twice on each carotid, the second analysis was delayed two months in order to mitigate recall bias. Two other observers manually measured the narrowest stenosis in mm, distal ICA in mm, and calculated NASCET percent stenosis in a blinded fashion. The calculated NASCET stenoses were categorized into mild, moderate, or severe. Chi square and analysis of variance (ANOVA) were used to test for statistical differences.
ANOVA did not find a statistically significant difference in the mean percent stenosis when comparing the two manual measurements, the two semi-automated measurements, and the repeat semi-automated. Chi square demonstrated that the distribution of grades of stenosis were statistically different (p<0.05) between the manual and semiautomated grades. Semi-automated vessel analysis tended to underestimate the degree of stenosis compared to manual measurement.
The mean percentage stenosis determined by semi-automated vessel analysis is not significantly different from manual measurement. However, when the data is categorized into mild, moderate and severe stenosis, there is a significant difference between semi-automated and manual measurements. The semi-automated software tends to underestimate the stenosis grade compared to manual measurement.
Reconnaissance survey in the Murzuq area, some 150 km south-east of Jarma, was carried out as part of the 2011 field programme of the Desert Migrations Project, with separate funding from the Leverhulme Trust for this element of work entitled the ‘Peopling the Desert Project’. This survey was designed to provide field verification of details of settlement systems identified and mapped from high-resolution satellite images in an area of c. 600 km2 immediately east of the oasis town of Murzuq. Examination of high-resolution QuickBird and Ikonos satellite imagery has permitted identification of a large dossier of more than 200 sites (fortified buildings known as qsur, other settlements, cemeteries, wells, fields/gardens and linear irrigation works called foggaras). The majority of these sites have never been previously noted or mapped and the date of the sites was unknown at the outset, though they clearly pertained to the historic periods. While further study of the finds and scientific dating evidence is required, the initial results of the brief field visit have major implications for our understanding of Garamantian and early Islamic settlement in south-eastern Fazzan.
Geoarchaeological surveys were conducted in northern Cyrenaica in 2009 as part of the TRANS-NAP project. A major objective of the project is to understand the relationship between regional environmental changes and human occupation patterns in northern Cyrenaica over approximately the past 200,000 years. This paper focuses on the results of surveys of the pre-desert and desert ecological zones in the south of the project's study region. The type, density and distribution of Palaeolithic sites were a particular focus of field research in the area. We report data from 42 archaeological sites in the pre-desert and desert zones, concentrating in particular on sites associated with palaeolakes and fan deposits. Analysis of the data reveals several patterns whereby particular archaeological signatures are associated with particular landforms. There is also a broader pattern across the region where sites assigned to the Middle Stone Age (MSA) period are considerably more common than those characteristic of the Late Stone Age (LSA). It is argued that this geographic area is particularly sensitive to changes in global climate and that past occupation patterns during the Palaeolithic were strongly driven by changes in the region's hydrological regime.
This paper reports the results of fieldwork conducted in the 2010 and 2011 DMP field seasons and of analysis of samples collected during these and previous years. Research has involved 1) studying palaeolake sediment outcrops, 2) using ground penetrating radar (GPR) to determine their extent under the Dahān Ubārī, and 3) coring palaeolakes in order to determine their palaeoenvironmental records. Research on these samples is continuing but some initial findings are discussed in this paper. The most extensive palaeolake sediments are found within the al-Mahruqah Formation and were deposited by a giant lake system that developed in the Fazzān Basin during past humid periods. Stratigraphic analysis of Lake Megafazzān sediments suggests two different sedimentary successions, a lake margin succession distinctive for its lacustrine and palaeosol carbonates, and a clastic-dominated, intensely rootleted, basin-centre succession which has terrestrial intervals (aeolian and palaeosols) as well as in the upper parts lacustrine limestones. Both basin margin and basin centre successions are underlain by fluvial deposits. Magnetostratigraphy suggests that the formation may be as old as the mid-Pliocene. After the Lake Megafazzān phase, smaller palaeolakes developed within the basin during subsequent humid periods. One of the largest is found in the Wādī al-Hayāt in the area between Jarma and Ubārī. Similar deposits further west along the Wādī at progressively higher altitudes are interpreted as small lakes and marshes fed by springs issuing from aquifers at the base of the escarpment, last replenished during the Holocene humid phase. Dating of sediments suggests that this was between c. 11 and c. 8 ka. The Wādī ash-Shāţī palaeolake core also provides a Holocene palaeoclimate record that paints a slightly different picture, indicating lake conditions until around 7 ka, whereupon it started oscillating until around 5.5 ka when sedimentation terminates. The reasons for the differences in these records are discussed.
The science of extra-solar planets is one of the most rapidly changing areas of astrophysics and since 1995 the number of planets known has increased by almost two orders of magnitude. A combination of ground-based surveys and dedicated space missions has resulted in 560-plus planets being detected, and over 1200 that await confirmation. NASA's Kepler mission has opened up the possibility of discovering Earth-like planets in the habitable zone around some of the 100,000 stars it is surveying during its 3 to 4-year lifetime. The new ESA's Gaia mission is expected to discover thousands of new planets around stars within 200 parsecs of the Sun. The key challenge now is moving on from discovery, important though that remains, to characterisation: what are these planets actually like, and why are they as they are?
In the past ten years, we have learned how to obtain the first spectra of exoplanets using transit transmission and emission spectroscopy. With the high stability of Spitzer, Hubble, and large ground-based telescopes the spectra of bright close-in massive planets can be obtained and species like water vapour, methane, carbon monoxide and dioxide have been detected. With transit science came the first tangible remote sensing of these planetary bodies and so one can start to extrapolate from what has been learnt from Solar System probes to what one might plan to learn about their faraway siblings. As we learn more about the atmospheres, surfaces and near-surfaces of these remote bodies, we will begin to build up a clearer picture of their construction, history and suitability for life.
The Exoplanet Characterisation Observatory, EChO, will be the first dedicated mission to investigate the physics and chemistry of Exoplanetary Atmospheres. By characterising spectroscopically more bodies in different environments we will take detailed planetology out of the Solar System and into the Galaxy as a whole.
EChO has now been selected by the European Space Agency to be assessed as one of four M3 mission candidates.
We present an in vitro model of human skin that, together with nonlinear optical microscopy, provides a useful system for characterizing morphological and structural changes in a living skin tissue microenvironment due to changes in oxygen status and proteolytic balance. We describe for the first time the effects of chronic oxygen deprivation on a bioengineered model of human interfollicular epidermis. Histological analysis and multiphoton imaging revealed a progressively degenerating ballooning phenotype of the keratinocytes that manifested after 48 h of hypoxic exposure. Multiphoton images of the dermal compartment revealed a decrease in collagen structural order. Immunofluorescence analysis showed changes in matrix metalloproteinase (MMP)-2 protein spatial localization in the epidermis with a shift to the basal layer, and loss of Ki67 expression in proliferative basal cells after 192 h of hypoxic exposure. Upon reoxygenation MMP-2 mRNA levels showed a biphasic response, with restoration of MMP-2 levels and localization. These results indicate that chronic oxygen deprivation causes an overall degeneration in tissue architecture, combined with an imbalance in proteolytic expression and a decrease in proliferative capacity. We propose that these tissue changes are representative of the ischemic condition and that our experimental model system is appropriate for addressing mechanisms of susceptibility to chronic wounds.