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The efficient and effective movement of research into practice is acknowledged as crucial to improving population health and assuring return on investment in healthcare research. The National Center for Advancing Translational Science which sponsors Clinical and Translational Science Awards (CTSA) recognizes that dissemination and implementation (D&I) sciences have matured over the last 15 years and are central to its goals to shift academic health institutions to better align with this reality. In 2016, the CTSA Collaboration and Engagement Domain Task Force chartered a D&I Science Workgroup to explore the role of D&I sciences across the translational research spectrum. This special communication discusses the conceptual distinctions and purposes of dissemination, implementation, and translational sciences. We propose an integrated framework and provide real-world examples for articulating the role of D&I sciences within and across all of the translational research spectrum. The framework’s major proposition is that it situates D&I sciences as targeted “sub-sciences” of translational science to be used by CTSAs, and others, to identify and investigate coherent strategies for more routinely and proactively accelerating research translation. The framework highlights the importance of D&I thought leaders in extending D&I principles to all research stages.
To identify potential participants for clinical trials, electronic health records (EHRs) are searched at potential sites. As an alternative, we investigated using medical devices used for real-time diagnostic decisions for trial enrollment.
To project cohorts for a trial in acute coronary syndromes (ACS), we used electrocardiograph-based algorithms that identify ACS or ST elevation myocardial infarction (STEMI) that prompt clinicians to offer patients trial enrollment. We searched six hospitals’ electrocardiograph systems for electrocardiograms (ECGs) meeting the planned trial’s enrollment criterion: ECGs with STEMI or > 75% probability of ACS by the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI). We revised the ACI-TIPI regression to require only data directly from the electrocardiograph, the e-ACI-TIPI using the same data used for the original ACI-TIPI (development set n = 3,453; test set n = 2,315). We also tested both on data from emergency department electrocardiographs from across the US (n = 8,556). We then used ACI-TIPI and e-ACI-TIPI to identify potential cohorts for the ACS trial and compared performance to cohorts from EHR data at the hospitals.
Receiver-operating characteristic (ROC) curve areas on the test set were excellent, 0.89 for ACI-TIPI and 0.84 for the e-ACI-TIPI, as was calibration. On the national electrocardiographic database, ROC areas were 0.78 and 0.69, respectively, and with very good calibration. When tested for detection of patients with > 75% ACS probability, both electrocardiograph-based methods identified eligible patients well, and better than did EHRs.
Using data from medical devices such as electrocardiographs may provide accurate projections of available cohorts for clinical trials.
A sensor which detects mechanical stresses and stores the position and the strength of these loads by color change of embedded quantum dots (QDs) is presented. The top and bottom electrodes of the sensor are inkjet-printed which leads to a fast and accurate deposition of thin (approx. 50 - 300 nm) and conductive layers. The used silver and poly(3,4-ethylenedioxythio-phene) polystyrene sulfonate (PEDOT:PSS) inks are optimized in terms of printability and opportunities of functionality forming without influencing the active layer of the sensor. The active layer of the sensor is spin-coated and consists of the QDs embedded in semi-conducting poly(9-vinylcarba-zole) (PVK). The hole transport characteristic of PVK and the band level alignment of the used materials ensures the preferred injection of only one type of charge carrier into the QDs. As a result the mechanical stress is visualized by a decreasing in photoluminescence (PL) of the QDs.
Lecture-capture software allows instructors to record their class presentations for students to review as necessary. Although this technology has long been considered too expensive for large-scale use, it is quickly becoming ubiquitous and deployable using ordinary computers and consumer-grade software. Using survey and final-grade data from a three-semester trial in a large introductory-level political science course, the authors demonstrate students almost universally approve of the technology and support its use in future classes. Students are most likely to use recordings when they study for exams and catch up on material after being absent from class. Additionally, certain subgroups—primarily international students and those who are performing poorly in the class—are more likely to watch archived recordings. However, these data demonstrate that positive evaluations and increased usage may not translate into better grades; viewing lectures does not appear to substantially improve individual performance.
We present our joint efforts to study variable stars in open clusters. This includes a new catalogue, a photometric survey for new variables, and the database WEBDA. Our tools will shed more light on stellar variability in open clusters.
The real-time electronic performance of a gallium nitride nanowire-based field effect transistor was investigated at five-minute intervals over thirty minutes of continuous irradiation by Xenon-124 relativistic heavy ions. An initial current surge that resulted in device improvement rather than device failure was observed. The current surge, and subsequent electronic behavior, was modeled using a combined thermionic emission-tunnelling approach, leading to information about barrier height, carrier concentrations, expected temperature behavior, and tunnelling.
A retrospective cross-sectional survey of self-reported acute gastrointestinal infection (AGI) incidence in the community was performed in Poland, from December 2008 to November 2009. The aim of the study was to estimate the magnitude and distribution of self-reported AGI, in order to calibrate the routine AGI surveillance system in Poland. The study population were randomly selected residents of all Polish regions, having a fixed telephone line. An equal number of telephone interviews were collected each month, requesting the interviewee to identify gastrointestinal symptoms that had occurred in the previous 4 weeks. The international AGI case definition was used. In total 3583 complete interviews were obtained. The compliance ratio was 26%. Of 3583 respondents, 240 (6·7%) individuals fulfilled the AGI case definition. The annualized incidence of acute gastroenteritis was 0·9/person-year (95% confidence interval 0·8–1·0). Comparison of the obtained annual AGI estimate (33·3 million infections) with the number of cases reported to national surveillance during the corresponding period (73 512), yielded an underreporting factor of 453 cases occurring in the community for each reported case. Of the 240 AGI cases, 30·4% consulted a general practitioner, and 4·6% were admitted to hospital. Samples for microbiological confirmation were collected from four (1·6%) cases. This first population-based study in eastern Europe has confirmed that AGI places a high burden on Polish society, which is underestimated by national surveillance data. Efforts are necessary to improve AGI reporting and diagnostic practices in order to increase the effectiveness of the Polish surveillance system in detecting threats related to new AGI pathogens, new routes of transmission or the potential for international spread.
Praseodymium oxide Pr2O3 (and Pr6O11) layers were deposited by innovative pulsed injection MOCVD technique on Si(100) in the temperature range 400-750°C. Praseodymium 2,2,6,6-tetramethyl-3,5-heptanedionate dissolved in monoglyme (1,2-dimethoxyethane) or toluene was used as precursor material. The influence of deposition conditions on film composition, growth rate, crystallization and surface roughness has been investigated. The main parameters influencing film composition and properties were substrate temperature and partial oxygen pressure during deposition. The presence of molecular oxygen in the reactor leads to the growth of Pr6O11 as the most stable phase or its mixture with PrO2, while deposition in inert atmosphere (Ar, 2 torr) allows to obtain Pr2O3 films which were amorphous or crystalline depending on the deposition temperature. Crystallized (polycrystalline) Pr2O3 films can be obtained at the growth temperatures 650°C and higher, while crystalline Pr6O11 films grow starting 400°C. Ex-situ annealing (750°C, vacuum, 2 hours) of the amorphous Pr2O3 films leads to film crystallization. Step coverage study has been performed for amorphous and crystallized Pr2O3 films. Electrical properties of thin (∼10 nm) Pr2O3 films were investigated and encouraging EOT (equivalent oxide thickness), leakage current data have been obtained.
To determine if a dedicated teaching attending for medical student education improves medical student, attending physician, and resident perceptions and satisfaction.
Two dedicated teaching attending physician shifts were added to the clinical schedule each week. A before-after trial compared medical student evaluations from 2000 to 2004 (preteaching attending physician) to medical student evaluations from 2005 to 2006 (teaching attending physician). Attending physician and resident perceptions and satisfaction with the teaching attending physician shifts using a 5-point Likert-type scale (1 = poor to 5 = excellent) were also assessed.
Eighty-nine (100%) medical students participated, with 63 preteaching attending physician and 26 teaching attending physician rotation evaluations. The addition of teaching attending physician shifts improved mean medical student satisfaction with bedside teaching (4.1 to 4.5), lecture satisfaction (4.2 to 4.8), preceptor scores (4.3 to 4.8), and perceived usefulness of the rotation (4.5 to 5.0) (all p < 0.05). Thirteen attending physicians (93%) participated in the crosssectional questionnaire. The addition of teaching attending physician shifts improved faculty ratings of their medical student interactions by ≥ 1.5 points for all items (p ≤ 0.001). Faculty perceptions of their resident interactions improved for quality of bedside teaching (3.1 to 4.0), their availability to hear resident presentations (3.4 to 4.2), and their supervision of residents (3.4 to 4.1) (p ≤ 0.01). Residents (n = 35) noted minor improvements with the timeliness of patient dispositions, faculty bedside teaching, and attending physician availability.
The addition of select teaching attending physician shifts had the greatest effect on medical student and faculty perceptions and satisfaction, with some improvements for residents.
Using high resolution TEM (HRTEM), we identified some process induced ‘weak spots’ in SiO2 layers: First, we observed thinning in the periphery of the transistor, i. e. near the boundary to the shallow trench isolation. At the boundary to the shallow trench, the Si substrate gradually changes its orientation from <100> to <110>, which results in an unexpected oxidation behavior in this region. Secondly, we observed the intrusion of poly-Si grains from the gate into the gate oxide, resulting in local thinning of the dielectric. Using image simulations, we show that conventional high resolution TEM can reveal the interface roughness only to a very limited extend.
Many metallic superlattices are known to exhibit dramatic anomalous elastic properties as a function of modulation wavelength. All measurements to date measure either a shear modulus or a longitudinal modulus in the superlattice plane. Here we present a method which also probes longitudinal elastic behavior perpendicular to the layers using a nano-hardness tester. In this method, a diamond tip is indented into the material and both the indentation depth and applied force are constantly monitored during loading and unloading. The elastic properties are extracted from the unloading part of the force versus displacement curve. Contrary to the anomaly found in a shear modulus, no anomaly in Young's modulus was found in the present study on Mo/Ni superlattices.
In contrast to sintered Bi2Sr2Ca1Cu2Oy (Bi-2212), melt processed material exhibits nonzero intergrain supercurrents at T < 77 K. By means of partial melting and long term annealing we achieved nonoriertted material with Jc(77) - 3500 A/cm2 (1μV/cm criterion) and Tc = 96 K. Zone melting leads to well textured bulk material with the c-axis of the crystallites oriented perpendicular to the pulling direction R, and thus to an anisotropie critical current density. The anisotropy factor is between 2 and 5. At low temperatures the melt textured ceramic exhibits higher critical currents than the nonoriented material. This is not true at high temperatures, since the latter has a higher critical temperature.
At 77 K and small fields both oriented and nonoriented ceramics exhibit no transition in their current-voltage characteristics, but obey the power law E = Eo(j/jo(H)) α(H) over a large range in E (10”−3-10”−3 V/cm). Measurements on the textured ceramic with magnetic fields parallel and perpendicular to the pulling direction demonstrate that the superconducting properties of these materials are only affected by the field components parallel to the c-axes of the crystallites. For fields parallel to the pulling direction the measured values of α(H), Jo(H) and of the reversible magnetization Mrev can be attributed to the misorientation of the Bi-2212 platelets which is in average about 14°.
Structural, optical and electrical properties of a-Si:H films prepared with the VHF Glow Discharge system were studied as function of deposition temperature, particularly in the range below 100°C. Usually, this material has poor optoelectronic properties. The a-Si:H material discussed in this work shows a surprisingly low hydrogen content, a low dihydride to monohydride ratio, good optical and electrical properties.
The reaction of a metal film with polycrystalline silicon to form a metal silicide has been shown to occur very rapidly when using cw lamp annealing in contrast to conventional furnace annealing. The faster reaction kinetics implies a more efficient energy coupling (radiative heating) versus the conductive/convective heat transfer processes which dominate furnace annealing. From Rutherford backscattering determinations of the thickness of PtSi formed as a function of anneal time (t), we have found the relationship to be linear in t with growth rates in the rangg 10−7–10−6 cm/sec (10 – 100Å/sec) for the temperature range 375 – 450° C. From these data the activation energy for the formation of PtSi was calculated to be 1.8± 0.2eV for cw lamp annealing, in reasonable agreement with literature values from conventional furnace annealing experiments.
A new technique for improving the diffusion barrier properties of thin, thermallyevaporated nickel, chromium and nichrome films on silicon is described. In this technique, known as “Rapid Thermal Annealing” (RTA), profound differences in the diffusion barrier properties of the films annealed in ammonia ambient at 550-750°C, in comparison to films annealed only in vacuum, were observed. The films annealed in ammonia retained their integrity while the films annealed in vacuum showed diffusion of the silicon into the metal overlayer throughout the entire thickness of the metal in some cases. The film sheet resistance increase for the latter was consistent with the formation of the metal silicide. The possibility of extending this technique to electroplated films used in integrated and hybrid device fabrication is being studied.
We have investigated the influence of substrate temperature on the optoelectronic and structural properties of heavily doped μc-Si:H, prepared with the Very High Frequency Glow Discharge process. At substrate temperatures as low as 160°C we obtain, for films with 0.5μm thickness, maximum conductivities of 100 S/cm and 20 S/cm for <n> and <p> material, respectively. Starting from these values the deposition parameters were optimised for ultrathin layers having thicknesses in the range of 100 to 500Å. We observe that boron doping plays a critical role in the crystallisation of ultrathin films. The thinnest layers investigated so far show conductivities of 0.2 S/cm at d=100Å for <n>, and 0.2 S/cm at d=250Å for <p> material. These properties make μc-Si:H films attractive candidates to form tunnel junctions in tandem solar cells.
Two wet chemical cleaning processes (a conventional chromic acid clean and an electrochemical etch) and a H-plasma exposure have been employed to clean natural type lib semiconducting diamond C(001) wafers. The effects of these processes on the diamond surface have been assessed and compared. As evidenced by Auger electron spectroscopy (AES), an oxygen free surface could be obtained following annealing to 900°C for the electrochemical process compared to 1050°C for the chromic acid etch. In addition, the technique of Atomic Force Microscopy (AFM) demonstrated the presence of oriented pits on the surface of samples electrochemically etched for long times at high currents. Furthermore, heteroepitaxial Cu films have been grown on the diamond substrates cleaned by a process as described above. By means of Ultraviolet Photoemission Spectroscopy (UPS) a Schottky barrier height of ΦB≊ 1.0 eV was measured. Furthermore, the presence a negative electron affinity (NEA) has been determined.
Thin Zr films were deposited on natural single crystal diamond (100) substrates by ebeam evaporation in ultra-high vacuum (UHV). Before metal deposition the surfaces were cleaned by UHV anneals at either 500°C or 1150°C. Following either one of these treatments a positive electron affinity was determined by means of UV photoemission spectroscopy (UPS). Depositing 2Å of Zr induced a NEA on both surfaces. Field emission current - voltage measurements resulted in a threshold field (for a current of 0.1 µA) of 79 V/µm for positive electron affinity diamond surfaces and values as low as 20 V/µm for Zr on diamond.
The properties and characteristics of vacuum microtriodes based on NEA diamond surfaces were modelled. Specifically, an NEA diamond vacuum microtriode array was investigated using electrical measurements, electron optics software, and microwave circuit simulation. Data for emission current versus applied voltage for various anode-to-cathode distances for diamond NEA surfaces was analyzed and various parameters were extracted. Electron optics software was used to determine Fowler-Nordheim and space-charge-limited DC I-V characteristics for each microtriode. Microwave circuit simulation was done to determine the behavior of arrays of these vacuum microtriodes in an RF amplifier circuit.