12 results
Search Results
2. A POWER TO INTRIGUE? EXPLORING THE 'TIMELESS' QUALITIES OF THE SO‐CALLED 'GROTESQUE' IRON AGE TORC FROM SNETTISHAM, NORFOLK.
- Author
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Joy, Jody
- Subjects
IRON Age ,HELPING behavior ,GROTESQUE ,CHARISMA ,CHRONOLOGY - Abstract
Summary: Sometimes we come across objects that truly intrigue us. Not necessarily because they are great examples of art, or because they are made of precious materials, but because there is some other quality which captures our attention. One of these can be age. Just as age adds character to people's faces, the patina of an object or visible signs of damage and use instils an object with a certain 'charisma' or 'aura'. This paper examines in detail the so‐called grotesque torc, a neck‐ring dating to the Iron Age which has been extensively repaired. The repairs are crude and obvious, which gives the object its distinctive appearance. It is argued that these signs of age, inscribed onto the artefact through its life, imbued the torc with a timeless 'anachronic' quality: its visible age manifests a certain charisma or aura, helping facilitate a plural relationship with time. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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3. Deep learning denoising of digital breast tomosynthesis: Observer performance study of the effect on detection of microcalcifications in breast phantom images.
- Author
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Chan, Heang‐Ping, Helvie, Mark A., Gao, Mingjie, Hadjiiski, Lubomir, Zhou, Chuan, Garver, Kim, Klein, Katherine A., McLaughlin, Carol, Oudsema, Rebecca, Rahman, W. Tania, and Roubidoux, Marilyn A.
- Subjects
DEEP learning ,TOMOSYNTHESIS ,BREAST imaging ,DIGITAL learning ,QUANTUM noise ,PERFORMANCE theory ,BREAST - Abstract
Background: The noise in digital breast tomosynthesis (DBT) includes x‐ray quantum noise and detector readout noise. The total radiation dose of a DBT scan is kept at about the level of a digital mammogram but the detector noise is increased due to acquisition of multiple projections. The high noise can degrade the detectability of subtle lesions, specifically microcalcifications (MCs). Purpose: We previously developed a deep‐learning‐based denoiser to improve the image quality of DBT. In the current study, we conducted an observer performance study with breast radiologists to investigate the feasibility of using deep‐learning‐based denoising to improve the detection of MCs in DBT. Methods: We have a modular breast phantom set containing seven 1‐cm‐thick heterogeneous 50% adipose/50% fibroglandular slabs custom‐made by CIRS, Inc. (Norfolk, VA). We made six 5‐cm‐thick breast phantoms embedded with 144 simulated MC clusters of four nominal speck sizes (0.125–0.150, 0.150–0.180, 0.180–0.212, 0.212–0.250 mm) at random locations. The phantoms were imaged with a GE Pristina DBT system using the automatic standard (STD) mode. The phantoms were also imaged with the STD+ mode that increased the average glandular dose by 54% to be used as a reference condition for comparison of radiologists' reading. Our previously trained and validated denoiser was deployed to the STD images to obtain a denoised DBT set (dnSTD). Seven breast radiologists participated as readers to detect the MCs in the DBT volumes of the six phantoms under the three conditions (STD, STD+, dnSTD), totaling 18 DBT volumes. Each radiologist read all the 18 DBT volumes sequentially, which were arranged in a different order for each reader in a counter‐balanced manner to minimize any potential reading order effects. They marked the location of each detected MC cluster and provided a conspicuity rating and their confidence level for the perceived cluster. The visual grading characteristics (VGC) analysis was used to compare the conspicuity ratings and the confidence levels of the radiologists for the detection of MCs. Results: The average sensitivities over all MC speck sizes were 65.3%, 73.2%, and 72.3%, respectively, for the radiologists reading the STD, dnSTD, and STD+ volumes. The sensitivity for dnSTD was significantly higher than that for STD (p < 0.005, two‐tailed Wilcoxon signed rank test) and comparable to that for STD+. The average false positive rates were 3.9 ± 4.6, 2.8 ± 3.7, and 2.7 ± 3.9 marks per DBT volume, respectively, for reading the STD, dnSTD, and STD+ images but the difference between dnSTD and STD or STD+ did not reach statistical significance. The overall conspicuity ratings and confidence levels by VGC analysis for dnSTD were significantly higher than those for both STD and STD+ (p ≤ 0.001). The critical alpha value for significance was adjusted to be 0.025 with Bonferroni correction. Conclusions: This observer study using breast phantom images showed that deep‐learning‐based denoising has the potential to improve the detection of MCs in noisy DBT images and increase radiologists' confidence in differentiating noise from MCs without increasing radiation dose. Further studies are needed to evaluate the generalizability of these results to the wide range of DBTs from human subjects and patient populations in clinical settings. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. Thunderstorms and extreme rainfall in south Norfolk, 16 August 2020: hydrological response and implications.
- Author
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Dent, James, Clark, Colin, and Holley, Dan
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THUNDERSTORMS ,RAINFALL ,FLOOD risk ,HUMIDITY ,EXTREME value theory ,RAINFALL measurement ,RAINSTORMS - Published
- 2022
- Full Text
- View/download PDF
5. A beachcomber's bonanza, or just another Micraster?
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BEACHES ,CHALK ,COASTS ,INVERTEBRATES - Abstract
The beach is where the ancient, in the shape of diverse erratics, meets the present in the shape of corrosion, encrusting shells and invertebrate borings. Many of us have favourite beach walks, repeated whenever possible, and educating us in the common and rare clasts that might be encountered in such an ever‐changing environment. After over 12 years of patrolling the coast of north Norfolk, in eastern England, I found a common Chalk echinoid—so why am I excited? [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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6. The Political Complexity of Coastal Flood Risk Reduction: Lessons for Climate Adaptation Public Works in the U.S.
- Author
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Rasmussen, D. J., Kopp, Robert E., Shwom, Rachael, and Oppenheimer, Michael
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FLOOD risk ,PUBLIC works ,FLOOD control ,COASTAL zone management ,STORM surges ,STORM damage ,SOCIAL conflict ,HAZARD mitigation - Abstract
Coastal climate adaptation public works, such as storm surge barriers and levees, are central elements of several current proposals to limit damages from coastal storms and sea‐level rise in the United States. Academic analysis of these public works projects is dominated by technocratic and engineering‐driven frameworks. However, social conflict, laws, political incentives, governance structures, and other political factors have played pivotal roles in determining the fate of government‐led coastal flood risk reduction efforts. Here, we review the ways in which politics has enabled or hindered the conception, design, and implementation of coastal risk reduction projects in the U.S. We draw from the literature in natural hazards, infrastructure, political science, and climate adaptation and give supporting examples. Overall, we find that (1) multiple floods are often needed to elicit earnest planning; (2) strong and continuous leadership from elected officials is necessary to advance projects; (3) stakeholder participation during the design stage has improved outcomes; (4) legal challenges to procedural and substantive shortcomings under environmental protection statutes present an enduring obstacle to implementing megastructure proposals. Plain Language Summary: Major U.S. cities like New York, Boston, Norfolk, and Houston are investigating the use of storm surge barriers, levees, and other coastal flood protection megaprojects to limit damages from coastal storms and sea‐level rise. Determining the feasibility of such public works projects is largely dominated by technocratic and engineering‐driven frameworks (for example, benefit‐cost analysis). However, experience with similar public infrastructure and natural hazard preparedness projects suggests that social conflict and politics have been crucial in their conception, design, and implementation. In this review, we highlight the role of interest mobilization, political leadership, stakeholder participation, and legal challenges as a result of environmental protection laws in both creating and overcoming political obstacles. Better understanding the social and political factors that enable or hinder the implementation of storm surge barriers, levees, and other coastal flood protection megaprojects could encourage strategies and policies that are less likely to result in deadlocks, delays, or failure, thus saving valuable time and planning resources. Key Points: Social conflict and politics are crucial factors in the conception, design, and implementation of coastal flood protection megaprojectsPolitical incentives can hinder efforts to add adaptation works to government agendasEnvironmental protection laws, siting issues, and fragmented decision‐making add complexity to implementation [ABSTRACT FROM AUTHOR]
- Published
- 2021
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7. Training Machine Learning Surrogate Models From a High‐Fidelity Physics‐Based Model: Application for Real‐Time Street‐Scale Flood Prediction in an Urban Coastal Community.
- Author
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Zahura, Faria T., Goodall, Jonathan L., Sadler, Jeffrey M., Shen, Yawen, Morsy, Mohamed M., and Behl, Madhur
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FLOOD warning systems ,FORECASTING ,MACHINE learning ,FLOOD risk ,FLOODS ,WATER depth - Abstract
Mitigating the adverse impacts caused by increasing flood risks in urban coastal communities requires effective flood prediction for prompt action. Typically, physics‐based 1‐D pipe/2‐D overland flow models are used to simulate urban pluvial flooding. Because these models require significant computational resources and have long run times, they are often unsuitable for real‐time flood prediction at a street scale. This study explores the potential of a machine learning method, Random Forest (RF), to serve as a surrogate model for urban flood predictions. The surrogate model was trained to relate topographic and environmental features to hourly water depths simulated by a high‐resolution 1‐D/2‐D physics‐based model at 16,914 road segments in the coastal city of Norfolk, Virginia, USA. Two training scenarios for the RF model were explored: (i) training on only the most flood‐prone street segments in the study area and (ii) training on all 16,914 street segments in the study area. The RF model yielded high predictive skill, especially for the scenario when the model was trained on only the most flood‐prone streets. The results also showed that the surrogate model reduced the computational run time of the physics‐based model by a factor of 3,000, making real‐time decision support more feasible compared to using the full physics‐based model. We concluded that machine learning surrogate models strategically trained on high‐resolution and high‐fidelity physics‐based models have the potential to significantly advance the ability to support decision making in real‐time flood management within urban communities. Key Points: Surrogate machine learning models were trained for flood prediction using a high‐resolution and high‐fidelity physics‐based modelThe surrogate model accurately emulated flooding depth and duration on streets simulated by the physics‐based modelA 3,000 times speedup was achieved with the surrogate model compared to the physics‐based model, making it attractive for real‐time decision support [ABSTRACT FROM AUTHOR]
- Published
- 2020
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8. Early data on long‐term efficacy and safety of inotersen in patients with hereditary transthyretin amyloidosis: a 2‐year update from the open‐label extension of the NEURO‐TTR trial.
- Author
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Brannagan, T. H., Wang, A. K., Coelho, T., Waddington Cruz, M., Polydefkis, M. J., Dyck, P. J., Plante‐Bordeneuve, V., Berk, J. L., Barroso, F., Merlini, G., Conceição, I., Hughes, S. G., Kwoh, J., Jung, S. W., Guthrie, S., Pollock, M., Benson, M. D., Gertz, M., Drachman, Brian, and Gorevic, Peter
- Subjects
PATIENT safety ,AMYLOIDOSIS ,DIABETIC neuropathies ,NEUROLOGICAL disorders ,PERIPHERAL nervous system - Abstract
Background and purpose: Hereditary transthyretin (hATTR) amyloidosis causes progressive polyneuropathy resulting from transthyretin (TTR) amyloid deposition throughout the body, including the peripheral nerves. The efficacy and safety of inotersen, an antisense oligonucleotide inhibitor of TTR protein production, were demonstrated in the pivotal NEURO‐TTR study in patients with hATTR polyneuropathy. Here, the long‐term efficacy and safety of inotersen are assessed in an ongoing open‐label extension (OLE) study. Methods: Patients who completed NEURO‐TTR were eligible to enroll in the OLE (NCT02175004). Efficacy assessments included the modified Neuropathy Impairment Score plus seven neurophysiological tests composite score (mNIS + 7), the Norfolk Quality of Life – Diabetic Neuropathy (Norfolk QOL‐DN) questionnaire total score and the Short‐Form 36 Health Survey (SF‐36) Physical Component Summary (PCS) score. Safety and tolerability were also assessed. Results: Overall, 97% (135/139) of patients who completed NEURO‐TTR enrolled in the OLE. Patients who received inotersen for 39 cumulative months in NEURO‐TTR and the OLE continued to show benefit; patients who switched from placebo to inotersen in the OLE demonstrated improvement or stabilization of neurological disease progression by mNIS + 7, Norfolk QOL‐DN and SF‐36 PCS. No new safety concerns were identified. There was no evidence of increased risk for grade 4 thrombocytopenia or severe renal events with increased duration of inotersen exposure. Conclusion: Inotersen slowed disease progression and reduced deterioration of quality of life in patients with hATTR polyneuropathy. Early treatment with inotersen resulted in greater long‐term disease stabilization than delayed initiation. Routine platelet and renal safety monitoring were effective; no new safety signals were observed. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
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9. Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions.
- Author
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Mellett, Claire L., Phillips, Emrys, Lee, Jonathan R., Cotterill, Carol J., Tjelta, Tor Inge, James, Leo, and Duffy, Callum
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SEA control ,GLACIAL landforms ,GLACIATION ,SEISMIC surveys ,ICE sheets ,MORAINES - Abstract
High‐resolution shallow sub‐bottom seismic survey data obtained for the Dudgeon windfarm site located 50 km offshore of the north Norfolk coast in the southern North Sea have revealed that the chalk bedrock in this area is overlain by sediments deposited during the Elsterian and Weichselian glacial periods. A buried N–S‐trending subglacial drainage channel (tunnel valley) filled with Swarte Bank Formation (MIS 12) sediments indicates that the maximum extent of the Elsterian ice‐sheet margin occurred further to the south. Detailed cross‐sections constructed from the seismic data reveal the presence of buried thrust‐block moraine system composed of deformed (folded and thrusted) Swarte Bank Formation sediments, lying beneath a younger sequence of sediments dominated by the glacigenic Bolders Bank Formation (MIS 2). The geometry of the folds and sense of offset on the thrusts, coupled with the morphology of the ridge‐like landforms within this buried moraine system, are consistent with deformation having occurred in response to ice‐push from the N/NE. The chalk bedrock that underlies the glaciotectonized sequence is thought to have provided an antecedent control on the location and preservation of this moraine system. A three‐phase model is proposed to explain the evolution of this thrust‐moraine complex that formed at the oscillating ice margin during the overall active retreat of the Elsterian ice sheet. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
10. Performance of the cone beam computed tomography‐based patient positioning system on the Gamma Knife Icon™.
- Author
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Xu, Andy Y., Wang, Yi‐Fang, Wang, Tony J. C., Cheng, Simon K., Elliston, Carl D., Savacool, Michelle K., Dona Lemus, Olga, Sisti, Michael B., and Wuu, Cheng‐Shie
- Subjects
PATIENT positioning ,CONE beam computed tomography ,RADIOSURGERY ,THERMOLUMINESCENCE ,IMAGE registration ,FRACTIONS ,DEVIATION (Statistics) - Abstract
Purpose: Cone beam computed tomography (CBCT) imaging has been implemented on the Leksell Gamma Knife® Icon™ for assessing patient positioning in mask‐based Gamma Knife radiosurgery. The purpose of this study was to evaluate the performance of the CBCT‐based patient positioning system as a tool for frameless Gamma Knife radiosurgery. Methods: Daily quality assurance (QA) CBCT precision test results from a 12‐month period were analyzed for the geometric accuracy and the stability of the imager. The performance of the image acquisition module and the image registration algorithm was evaluated using an anthropomorphic head phantom (CIRS Inc., Norfolk, VA) and a XYZR axis manual positioning stage (TOAUTO Inc., Guangdong, China). The head phantom was fixed on a mask adaptor and manually translated in the X, Y, Z directions or rotated around the X, Y, Z axes in the range of ±10 mm or ±10º. A CBCT scan was performed after each manual position setup followed by an image registration to the reference scan. To assess the overall setup uncertainties in fractionated treatment, two cylindrical Presage phantoms (Heuris Inc., Skillman, NJ) of 15 cm diameter and 10 cm height were irradiated with identical prescription dose and shot placement following standard mask‐based treatment workflow according to two different fraction schedules: a single fraction treatment of 7.5 Gy and a 5‐fraction treatment with 1.5 Gy per fraction. Results: The averaged vector deviations of the four marks from their preset values are 0.087, 0.085, 0.095, and 0.079 mm from the 212 daily QA tests. The averaged displacements in the X, Y, Z coordinates and the pitch, yaw, roll angles from the image registration tests are 0.23, 0.27, 0.14, 0.32º, 0.19º, 0.31º from the manual setup. The corresponding maximum differences are 0.41, 0.33, 0.29 mm, 0.45º, 0.31º, and 0.43º, respectively. Compared to the treatment plan using the 2% & 1 mm criteria, the averaged 2D Gamma passing rate is 98.25% for the measured dose distribution from the Presage phantom with 1‐fraction irradiation and 95.12% for the 5‐fraction irradiation. The averaged Gamma passing rates are 99.53% and 98.16% for the 1‐fraction and 5‐fraction irradiations using the 2% & 2 mm criteria. Conclusions: The CBCT imager and the image registration algorithm can reproduce phantom position with <0.5 mm/0.5º uncertainty. A systematic contribution from the interfraction phantom repositioning procedure was observed in the Gamma analysis over the irradiated volumes of two end‐to‐end test phantoms. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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11. Problem-Solving Strategies of Sixth-Grade Students Who Are Superior Problem Solvers.
- Author
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Mandell, Alan
- Subjects
SCHOOL children ,PROBLEM solving ,GIFTED children ,STUDENT attitudes ,CRITICAL thinking ,PROBLEM-based learning ,EDUCATION research - Abstract
The article investigates the problem-solving strategies of sixth-grade students who are superior problem solvers by researchers from Norfolk, Virigina. In this study, the researchers attempt to find common problem-solving behaviors and strategies used by the subjects across several types of problems. The use of audiotaped problem-solving sessions appear to be an effective method for discovering how subjects solve problems. The use of predesigned behaviors classification scheme, such as the one employed in this study, makes it possible to discover the problem-solving behaviors and strategies of individuals and groups.
- Published
- 1980
12. Deprivation, Incentives and Mental Illness: An Application of Motivator-Hygiene Theory of Motivational Patterns and Economic Variables Among the Black, Working Poor.
- Author
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Nickson Jr., Jack W. and Karp, H. B.
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HYGIENE ,BLACK people ,ATTITUDES toward work ,MENTAL health - Abstract
The article presents an application of motivator-hygiene theory among the black, working poor. Briefly stated, the motivator-hygiene theory demonstrates that man has two separate and independent need systems that do not interact. The hygiene continuum deals with man's need to avoid pain from his environment and is met by increasing extrinsic job factors such as salary, status, company policy and administration, good interpersonal relationships, etc. It is the hygiene factors that keep man from states of dissatisfaction. Thus, explicit to motivator-hygiene theory is the hypothesis that satisfaction and dissatisfaction are separate and independent conditions of job attitudes. The opposite of satisfaction is not dissatisfaction, rather, it is simply no satisfaction. The population sampled for this study consisted of a group of the black working poor in Norfolk, Virginia. This particular sample was chosen for several reasons. Since the study specifically attempts to ascertain attitudes about the work situation, it was only proper that interviews be held with some of those who were working. Poor and black workers were selected so as to ascertain whether or not this replication would further verify the motivator-hygiene theory, which had not yet been tested on such poor or black populations.
- Published
- 1974
- Full Text
- View/download PDF
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