Zinc tin oxide transistors on flexible substrates Jackson, W.B.; Herman, G.S.; Hoffman, R.L. ...
Journal of non-crystalline solids,
06/2006, Letnik:
352, Številka:
9-20
Journal Article, Conference Proceeding
Recenzirano
Flexible transistors were fabricated by sputter deposition of zinc tin oxide (ZTO) onto plasma-enhanced chemical vapor deposited gate dielectrics formed on flexible polyimide substrates with aluminum ...gate electrodes. Using output characteristics, the contact resistance of Al/ZTO contacts was found to be in the range of 100kΩ causing significant on-current degradation. ZTO transistors with indium tin oxide (ITO) contacts exhibited high on-currents of 1.5mA, on/off ratios of 106, subthreshold voltage slopes of 1.6V/decade, threshold voltages of −8.8V, and mobilities of 14cm2V−1s−1. Capacitance measurements are shown to be useful for assessing contact resistance.
The influence of chlorophyll shading on ocean dynamics has been usually disregarded in eastern boundary upwelling systems modeling studies in spite of their very high primary productivity. Here, we ...study how this effect impacts on the Peru upwelling system using a regional mesoscale‐resolving physical biogeochemical coupled model. We show that the shading effect leads to a surface cooling of up to 1°C on the shelf due to subsurface cooling of the source waters during their transit toward the shelf. The shading effect leads to a more realistic subsurface stratification, a slowdown of the alongshore currents, and a shoaling of the oxycline. Impacts on the regional model biases show that the shading effect needs to be taken into account in both physical and coupled physical‐biogeochemical regional models of upwelling systems.
Plain Language Summary
The chlorophyll pigments of phytoplankton capture the downward penetrating solar energy to produce photosynthesis and warm the surface of the ocean. However, this effect is seldom taken into account in ocean models, in particular in upwelling systems where chlorophyll concentration is very high. In this study, we show that taking into account this effect in a model of the Peruvian upwelling system, one of the most productive systems in the world, modifies not only the temperature, circulation, and turbulence, but also stimulates nearshore phytoplankton production and deoxygenation over the shelf. This study shows that this effect needs to be parameterized in future modeling studies.
Key Points
The influence of surface chlorophyll shading on the Peru upwelling system is investigated using a physical biogeochemical coupled model
The shading effect leads to surface cooling, nutricline and oxycline shoaling, and phytoplankton increase on the shelf
The shading effect should be taken into account in high‐resolution eastern boundary upwelling System models
To evaluate the accuracy of identification of central and segmental chronic thromboembolic disease on helical computed tomographic (CT) scans and on magnetic resonance (MR) images.
Radiologic ...findings in 55 patients suspected of having chronic thromboembolic pulmonary hypertension were analyzed; these included findings from angiography (n = 55), helical CT (n = 47), and MR imaging (n = 26). Forty patients underwent thromboendarterectomy. CT and MR images were independently interpreted by two readers for the presence of thromboembolic material in central and segmental vessels. Surgical findings and angiographic findings were the reference standards for disease in central and segmental vessels, respectively.
Central vessel disease was determined more accurately with helical CT scans (accuracy of 0.79 for each of the two readers) than with angiograms (accuracy of 0.74) or with MR images (accuracy of 0.39 and 0.46 for two readers). Segmental vessel disease was also more accurately determined with CT scans (accuracy of 0.75 and 0.76 for two readers) than with MR images (accuracy of 0.61 and 0.57 for two readers).
Helical CT is a useful alternative to conventional angiography for diagnosis of chronic thromboembolism but may not be sufficient for selecting candidates for surgery in all cases.
•Reporting errors and reporting biases are relevant concerns for innovation research.•Reporting errors are found in 45% of all articles and 4% of all tests.•Discontinuities at conventional thresholds ...of statistical significance indicate reporting biases.•Uncertainty due to rounding of published results is taken into account.
Errors and biases in published results compromise the reliability of empirical research, posing threats to the cumulative research process and to evidence-based decision making. We provide evidence on reporting errors and biases in innovation research. We find that 45% of the articles in our sample contain at least one result for which the provided statistical information is not consistent with reported significance levels. In 25% of the articles, at least one strong reporting error is diagnosed where a statistically non-significant finding becomes significant or vice versa using the common significance threshold of 0.1. The error rate at the test level is very small with 4.0% exhibiting any error and 1.4% showing strong errors. We also find systematically more marginally significant findings compared to marginally non-significant findings at the 0.05 and 0.1 thresholds of statistical significance. These discontinuities indicate the presence of reporting biases. Explorative analysis suggests that discontinuities are related to authors’ affiliations and to a lesser extent the article’s rank in the issue and the style of reporting.
To describe the occurrence and importance of intravascular gas at ultrasonography (US) during the initial examination of patients after blunt abdominal trauma.
Reports of all abdominal US ...examinations performed at one institution for blunt trauma from October 1995 through June 1996 were reviewed. The charts of patients with intravascular gas were examined to determine the mechanism of injury, associated findings, and clinical outcome.
A total of 730 patients underwent abdominal US examinations during the 9 months of study; five had intravascular gas demonstrated. Two patients had portal venous gas, one had hepatic venous gas, and two had inferior vena caval gas. Four of the five patients were involved in motor vehicle accidents, and one had been assaulted. In patients in whom follow-up studies were obtained, there was no evidence of intravascular gas at US or computed tomography. No cause was found at imaging or clinical examination.
Intravascular gas may occur as a transient incidental finding after blunt abdominal trauma.
The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R_{2γ}, a direct measure of the contribution of hard two-photon ...exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of ≈20° to 80°. The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved gas electron multiplier and multiwire proportional chamber detectors at 12°, as well as symmetric Møller or Bhabha calorimeters at 1.29°. A total integrated luminosity of 4.5 fb^{-1} was collected. In the extraction of R_{2γ}, radiative effects were taken into account using a Monte Carlo generator to simulate the convolutions of internal bremsstrahlung with experiment-specific conditions such as detector acceptance and reconstruction efficiency. The resulting values of R_{2γ}, presented here for a wide range of virtual photon polarization 0.456<ε<0.978, are smaller than some hadronic two-photon exchange calculations predict, but are in reasonable agreement with a subtracted dispersion model and a phenomenological fit to the form factor data.
Filaments and fronts play a crucial role for a net offshore and downward nutrient transport in Eastern Boundary Upwelling Systems (EBUSs) and thereby reduce regional primary production. Most studies ...on this topic are based on either observations or model simulations, but only seldom are both approaches are combined quantitatively to assess the importance of filaments for primary production and nutrient transport.
Here we combine targeted interdisciplinary shipboard observations of a cold filament off Peru with submesoscale-permitting (1/45∘) coupled physical (Coastal and Regional Ocean Community model, CROCO) and biogeochemical (Pelagic Interaction Scheme for Carbon and Ecosystem Studies, PISCES) model simulations to (i) evaluate the model simulations in detail, including the timescales of biogeochemical modification of the newly upwelled water, and (ii) quantify the net effect of submesoscale fronts and filaments on primary production in the Peruvian upwelling system. The observed filament contains relatively cold, fresh, and nutrient-rich waters originating in the coastal upwelling. Enhanced nitrate concentrations and offshore velocities of up to
0.5 m s−1 within the filament suggest an offshore transport of nutrients. Surface chlorophyll in the filament is a factor of 4 lower than at the upwelling front, while surface primary production is a factor of 2 higher. The simulation exhibits filaments that are similar in horizontal and vertical scale compared to the observed filament. Nitrate concentrations and primary production within filaments in the model are comparable to observations as well, justifying further analysis of nitrate uptake and subduction using the model. Virtual Lagrangian floats were released in the subsurface waters along the shelf and biogeochemical variables tracked along the trajectories of floats upwelled near the coast. In the submesoscale-permitting (1/45∘) simulation, 43 % of upwelled floats and 40 % of upwelled nitrate are subducted within 20 d after upwelling, which corresponds to an increase in nitrate subduction compared to a mesoscale-resolving (1/9∘) simulation by 14 %. Taking model biases into account, we give a best estimate for subduction of upwelled nitrate off Peru between 30 %– 40 %. Our results suggest that submesoscale processes further reduce primary production by amplifying the downward and offshore export of nutrients found in previous mesoscale studies, which are thus likely to underestimate the reduction in primary production due to eddy fluxes. Moreover, this downward and offshore transport could also enhance the export of fresh organic matter below the euphotic zone and thereby potentially stimulate microbial activity in regions of the upper offshore oxygen minimum zone.
To determine the prevalence of unilateral hypoperfusion in patients suspected to have chronic thromboembolism (CTE), to identify the most common cause of hypoperfusion, and to compare the accuracy of ...helical computed tomographic (CT) angiography with that of conventional angiography in helping to determine the cause.
Radionuclide lung scan reports showed asymmetric hypoperfusion in 47 of 410 consecutive patients referred because of suspected CTE. Twenty-seven patients had unilateral or predominantly unilateral perfusion abnormalities. Each pulmonary angiogram and CT angiogram in these patients was interpreted independently by two readers blinded to clinical information and surgical outcome. Surgical confirmation of the diagnosis was available in 39 of the 47 patients with asymmetric hypoperfusion.
Unilateral (n = 11) or predominantly unilateral hypoperfusion (n = 16) was found in 6.6% (27 of 410 patients) of patients referred, and CTE was the most common cause. The accuracies of CT angiogram readers (reader 1, 83%; reader 2, 89%) were greater than those of conventional angiogram readers (reader 1, 73%; reader 2, 65%) for distinguishing CTE from other causes.
Unilateral hypoperfusion occurred in 6.6% of our study population, most frequently because of CTE. CT angiography is an excellent diagnostic alternative to conventional angiography for distinguishing patients with CTE from those with other causes.
The OLYMPUS experiment Milner, R.; Hasell, D.K.; Kohl, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2014, Letnik:
741
Journal Article
Recenzirano
Odprti dostop
The OLYMPUS experiment was designed to measure the ratio between the positron–proton and electron–proton elastic scattering cross-sections, with the goal of determining the contribution of two-photon ...exchange to the elastic cross-section. Two-photon exchange might resolve the discrepancy between measurements of the proton form factor ratio, μpGEp/GMp, made using polarization techniques and those made in unpolarized experiments. OLYMPUS operated on the DORIS storage ring at DESY, alternating between 2.01GeV electron and positron beams incident on an internal hydrogen gas target. The experiment used a toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight detectors to measure rates for elastic scattering over the polar angular range of approximately 25°–75°. Symmetric Møller/Bhabha calorimeters at 1.29° and telescopes of GEM and MWPC detectors at 12° served as luminosity monitors. A total luminosity of approximately 4.5fb−1 was collected over two running periods in 2012. This paper provides details on the accelerator, target, detectors, and operation of the experiment.
The dissociation of HOCl in its electronic ground state is investigated by means of quantum dynamics calculations (filter diagonalization and harmonic inversion of the autocorrelation function) and ...an ab initio potential energy surface. At threshold, the state-resolved rate constants are scattered over seven orders of magnitude, which is significantly broader than the distribution predicted by random matrix theory. This remarkable state specificity is the fingerprint of the regular dynamics of HOCl even at high energies.
PDF
