348 research outputs found
Association of retroplacental blood with basal plate myofibers
No full textObjectives: Diagnosed clinical abruption showing blood clot should be signed out in the pathology report as retroplacental hemorrhage with or without parenchymal indentation, and submitted clot separate from the placenta should be weighed. In our experience some cases sent as clinical abruptions have been cases of morbid adherence. This study was undertaken to evaluate the association of retroplacental blood with basal plate myofibers (BPMF).
Methods: 156 placentas reviewed by a board certified pediatric pathologist at a community hospital were evaluated for significant retroplacental blood. Basal plates were reviewed for deviations from normal.
Results: 33/156 placentas (21%) had significant retroplacental blood. 21/156 (13%) had a separate clot, of which 11/21 (52%) had basal plate myofibers (BPMF). 11 BPMF‐associated separate clots ranged from 10.5‐60 gms (average 23); while the clots of 10 cases with no demonstrated BPMF ranged from 19‐440 gms (average 82), tending to be larger (p<.03). Basal plate damage prior to delivery was noted in both sets of placentas. BPMF placentas could have myometrial damage prior to delivery.
Conclusions: Since BPMF may confer a risk for accreta in a subsequent pregnancy, submission of a separate clot with the placenta should lead the pathologist to evaluate for basal plate myofibers on H&E, and consider if there is an evidencebased indication to do an actin stain; before presuming a diagnosis of abruption.Peer reviewedAbstract published as Wyand, R. Cramer, S., Oshri, A., Heller, D. (2017). Association of retroplacental blood with basal plate myofibers. Placenta, 57, 280. http://dx.doi.org/10.1016/j.placenta.2017.07.18
Dynamics of direct X-ray detection processes in high-Z Bi<sub>2</sub>O<sub>3</sub> nanoparticles-loaded PFO polymer-based diodes
Get PDFSemiconducting polymer based X-ray detectors doped with high-Z nanoparticles hold the promise to combine mechanical flexibility and large-area processing with a high X-ray stopping power and sensitivity. Currently, a lack of understanding of how nanoparticle doping impacts the detector dynamics impedes the optimization of such detectors. Here, we study direct X-ray radiation detectors based on the semiconducting polymer poly(9,9-dioctyfluorene) blended with Bismuth(III)oxide (Bi2O3) nanoparticles (NPs). Pure polymer diodes show a high mobility of 1.3 × 10-5 cm2/V s, a low leakage current of 200 nA/cm2 at -80 V, and a high rectifying factor up to 3 × 105 that allow us to compare the X-ray response of a polymer detector in charge-injection conditions (forward bias) and in charge-collection conditions (reverse bias), together with the impact of NP-loading in the two operation regimes. When operated in reverse bias, the detectors reach the state of the art sensitivity of 24 μC/Gy cm2, providing a fast photoresponse. In forward operation, a slower detection dynamics but improved sensitivity (up to 450 ± 150 nC/Gy) due to conductive gain is observed. High-Z NP doping increases the X-ray absorption, but higher NP loadings lead to a strong reduction of charge-carrier injection and transport due to a strong impact on the semiconductor morphology. Finally, the time response of optimized detectors showed a cut-off frequency up to 200 Hz. Taking advantage of such a fast dynamic response, we demonstrate an X-ray based velocity tracking system.Novel Aerospace Material
Quantum error correction with spins in diamond
No full textDigital information based on the laws of quantum mechanics promisses powerful new ways of computation and communication. However, quantum information is very fragile; inevitable errors continuously build up and eventually all information is lost. Therefore, realistic large-scale quantum information processing requires the protection of quantum bits (qubits) against errors. In this thesis we present the experimental implementation of quantum error correction protocols based on spins in diamond. In such protocols, a quantum state is protected against errors by encoding in multiple qubits. Errors can be detected and corrected by measurement of correlations, so-called stabilizer-measurements, on these qubits.The experimental work presented in this thesis employs multiple spins in diamond as qubits to explore and implement error correction protocols. The nitrogen-vacancy (NV) centre in diamond is a lattice defect consisting of a nitrogen atom (N) and a vacancy (V) on two adjacent diamond lattice sites. This defect effectively results in an electronic spin that can be addressed as a qubit. The spin state can be manipulated by microwave fields and optically read out. At liquid helium temperatures (cryogenic temperature, ~4 K = -269 C), the NV electron spin provides high-fidelity single-shot readout and long coherence times.The NV centre is surrounded by naturally available (1.1% abundance) nuclear C13 spins. As the number of spins that are close enough to the NV centre to be strongly coupled is limited, we employ the weakly coupled nuclear spins in the spin bath of the NV centre. Using dynamical decoupling techniques these nuclear spins can be detected via the NV electron spin through the hyperfine interaction. The nuclear spins are long-lived and robust against optical excitation of the NV electron spin, which can make these spins a robust quantum register for quantum error correction.In Ch. 4 we demonstrate universal control over multiple of such weakly coupled nuclear C13 spins in the environment of the NV centre at ambient temperatures. We demonstrate initialization, control and read-out of individual nuclear spins. Finally, we implement a quantum error correction protocol by encoding a quantum state in the NV electron spin and two nuclear spins. Errors are detected by un-encoding the quantum state back to the electron spin and correction via a double controlled operation.For universal fault-tolerant quantum computations it is essential that the quantum information remains encoded at all times. In Ch. 5 we present multiple rounds of quantum error correction and active feedback on a continuously encoded qubit at cryogenic temperatures. A quantum state is protected by encoding in three weakly coupled spins. Errors are detected via high-fidelity non-demolition readout of the NV electron spin and actively corrected using fast classical electronics. We demonstrate that an actively error-corrected qubit is robust against phase flip errors and show that a superposition state can live longer than the best physical qubit in the encoding.The presented methods and results can be extended to a range of future experiments. In Ch. 6 we propose the implementation of five-qubit quantum error correction, the smallest code to correct for general single-qubit errors on the physical qubits in the encoding, by extending the experimental methods as developed in Chs. 4&5. Besides the exploration and development of larger error correction protocols and fault-tolerant quantum computing, the presented quantum register based in spins in diamond can be employed as a quantum node and combined with recent advances in the realization of quantum entanglement over large distances to form quantum networks. These networks can be used to study both fundamental questions as well as future applications in quantum information technology
The effects of attitudes about economic inequality on support for markets and democracy in Latin America, 1995-2010
No full textThe potential effects of economic inequality on markets and democracy have received significant attention in recent years. Less attention, however, has been devoted to empirically examining the attitudinal aspects of these relationships. In this dissertation, I examine the effects of attitudes about inequality on attitudes about government regulation of the economy, illiberal democracy, and civic engagement. I examine these effects with nine multilevel data sets spanning 1995-2010 and in the Latin America context. The statistical findings provide weak empirical support for the hypothesis that greater dissatisfaction with inequality is associated with greater support for a more government-regulated economy. They also suggest that dissatisfaction with inequality is not systematically related to support for illiberal democracy. Furthermore, the findings provide weak empirical evidence that dissatisfaction with inequality is systematically related to civic engagement. Moreover, the effects of dissatisfaction with inequality on support for these three individual-level outcomes do not appear to be systematically conditioned by various individual- and country-level factors. Therefore, the results suggest that attitudes about economic inequality are not consistently related to various attitudes about markets and democracy in the recent Latin American context. The findings help adjudicate between competing claims about the effects of economic inequality on markets and democracy, and they also shed light on the potential durability of markets and democracy in 21st century Latin America in the wake of widespread public dissatisfaction with economic inequality.Ph. D.Includes bibliographical referencesIncludes vitaby Brain D. Crame
Categorical and coordinate visuospatial processing in younger and older adults
No full textIn this thesis, four experiments were conducted in which participants made a categorical or coordinate spatial relation judgement concerning the location of a dot in relation to a bar. The main aim was to investigate how, if at all, categorical and coordinate VS processes changed with older age. In addition, the importance of task demand and the underlying cognitive processes involved in categorical and coordinate VS judgements were also examined.
In every experiment participants were faster and more accurate to make categorical visuospatial judgements than coordinate visuospatial judgements. This was taken to suggest that categorical visuospatial judgements are less demanding than coordinate visuospatial judgements. Younger adults were also found to process visuospatial information more quickly than older adults; however, accuracy rates and discrimination ability were similar. Furthermore, in contrast to expectation, coordinate visuospatial processes were not disproportionately affected by age-related decline.
Processing of categorical and coordinate visuospatial judgements was found to be affected by the distance of the dot from the bar and by the visual field in which stimuli were presented. However, the inconsistent effects of visual field across experiments made interpretation of these findings difficult.
Experiment 4 examined patterns of eye movements associated with categorical and coordinate visuospatial processes to gain insight into the underlying cognitive processes. The results indicated that visuospatial cognitive processing that occurs for above/below and near/far judgements is often qualitatively different from that which occurs when the task required precise distance estimation.
In conclusion, the experiments presented in this thesis provide significant insight into the cognitive processes associated with categorical and coordinate visuospatial judgements
The impacts of short break provision on disabled children and families: an international literature review
No full textFor over 30 years, short breaks have been part of the landscape of support provision for families with a disabled child. Historically, the term ‘respite care’ has been used in much of the research literature concerning short breaks for families with a disabled child. However, ‘short breaks’ has become the preferred term, partly due to the negative connotations of family carers requiring ‘respite’ from their children, and partly because short breaks now encompass a much wider range of supports than out-of-home placement in specialist residential facilities (Cramer and Carlin, 2008). As such, the term ‘short breaks’ will be used throughout this review, with the exception of direct quotes from research studies where the term ‘respite’ is used by study participants or study authors
Science under sail : ocean science education program combines traditional vessels with state-of-the-art technology
No full textAuthor Posting. © Oceanography Society, 2004. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 17, 3 (2004): 42-51, doi: 10.5670/oceanog.2004.29.Sea Education Association (SEA), located in Woods Hole, Massachusetts, offers introductory
oceanographic instruction in the classroom and hands-on research
training at sea to create a unique educational experience for undergraduate students
and other groups. Founded by Corwith Cramer in 1971, SEA has been
taking students to sea for over 30 years, first on the 125-foot research vessel
R/V Westward, and now on two custom-built Sailing School Vessels, the
134-foot steel brigantines SSV Corwith Cramer and SSV Robert
C. Seamans. SEA vessels have sailed over 800,000 miles
in the Atlantic and Pacific Oceans, and educated over 7,000
students in oceanography, nautical science, and in maritime history, literature,
and policy. This article describes recent developments and opportunities
in oceanographic education and research at SEA.The material presented herein is based
upon work supported by the National
Science Foundation under Grant No.
0087528 (SSV Robert C. Seamans) and
Grant No. 0213780 (SSV Corwith Cramer)
UA1C11/105/24 Phi Mu Composite
No full textPhi Mu Sorority top row l to r: Lauren Hanson, Amy Henson, Chrissy Dunn, Rebecca Whipple, Lori Martin, Ashley Gelhausen, Sarah Wesley, Kristina Zoglmann, Heather Schepers, Nichoel Pedigo, Erica Gipson, Leandra Rice. 2nd row l to r: Brooke Fielder, Lindsay Duncan, Deon Werle, Jennifer Burchell, Darcy Smith, Carla Coleman, Amanda Owen, Karey Hilbert, Melissa Hollis, Melissa Fryer, Amibeth Lovan, Dana Russell, Sara West. 3rd row l to r: Kimmi Grist, Cynthia Tipton, Julie Zoglmann, Jaclyn Phelps, Lara Kos, Chriscelyn Snell, Brooke Baker, Nicole Heller. 4th row l to r: Amanda Shanklin, Layla Pryor, Breeann Buschor, Elizabeth Pemberton, Ashley Dale, Holly Lewis. 5th row l to r: Miranda Mallory, Kara Nelson, Allison Wegley, Sabrina Clan, Bridget Bruner, Angela Brett, Danielle Scott, Amy Douglas, Brooke Cramer, Loren Colvin, Clarissa Puckett, Amber Calta, Stephanie Gladney, 6th row l to r: Emily Hock, Birana Arena, Sarah Gentry, Amanda Baird, Mary Little, Leigh Struble, Christina Tucker, Beth Tabor, Jennifer Rakestraw, Angela Usleton, Alison McFarland, Julie Ransom, Amy Stevens. 7th row l to r: Lindsey Spence, Katie Dugger, Jennifer Vetter, Daphne Brinkley, Neena Guimond, Jennifer Anderson, Leslie Bennett, Lorelei Esker, Kimberly Sutton, Jessica Hess, Jessica Cunningham, Jodi Lindaman, Jane Hughes
Joint Angle and Delay Estimation Algorithm
No full textThis report investigates the recently proposed signal processing algorithm JADE. JADE (Joint Angle & Delay Estimation) is a closed-form sub- space algorithm capable of simultaneously estimating the direction of arrival and delay of signals received by an antenna array and automatically pairing the estimated parameters. The performance of JADE is largely unknown. Therefore the purpose of this report is to explore the performance of JADE. Two aspects of the performance envelope of JADE are investigated; The performance under ideal conditions and the performance with diffuse scattering that is considered a less than ideal condition. This is done by using computer simulations. From the simulations one can conclude that JADE performs very well under ideal conditions, the variance of its estimates are very close to the theoretically lower bound, which is the Cramer-Rao bound. Also evident from the simulation is that diffuse scattering degrades the performance of JADE, but the variances of the angle and delay estimates are still less than the angular width and delay spread of the received ray, respectively. The performance of JADE improves by making the data matrix large with shifted and conjugated copies of itself. Although the results are positive, JADE is not fully developed, improvements like incorporating Doppler shifts estimation and fading estimation are some of the possibilities.Electrical Engineering, Mathematics and Computer ScienceTelecommunicatie- en Verkeersbegeleidingssysteme
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