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Facilitating Real-Time, Multidirectional Learning for Clinicians in a Low-Evidence Pandemic Response
- Richard C Hunt, Sofia P Braunstein, Lauren Cuddy Egbert, Katherine A Gorbach, Monisha Rao, Jonathan D Pearson, Amy J Armistad, Sanjeev Arora, Celine A Bennett, Amanda M Dezan, Jack Herrmann, John T Redd, B. Tilman Jolly, Jon R Krohmer, Bruce B Struminger
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- Journal:
- Disaster Medicine and Public Health Preparedness / Volume 17 / 2023
- Published online by Cambridge University Press:
- 21 September 2022, e246
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As COVID-19 was declared a health emergency in March 2020, there was immense demand for information about the novel pathogen. This paper examines the clinician-reported impact of Project ECHO COVID-19 Clinical Rounds on clinician learning. Primary sources of study data were Continuing Medical Education (CME) Surveys for each session from the dates of March 24, 2020 to July 30, 2020 and impact surveys conducted in November 2020, which sought to understand participants’ overall assessment of sessions. Quantitative analyses included descriptive statistics and Mann-Whitney testing. Qualitative data were analyzed through inductive thematic analysis. Clinicians rated their knowledge after each session as significantly higher than before that session. 75.8% of clinicians reported they would ‘definitely’ or ‘probably’ use content gleaned from each attended session and clinicians reported specific clinical and operational changes made as a direct result of sessions. 94.6% of respondents reported that COVID-19 Clinical Rounds helped them provide better care to patients. 89% of respondents indicated they ‘strongly agree’ that they would join ECHO calls again.COVID-19 Clinical Rounds offers a promising model for the establishment of dynamic peer-to-peer tele-mentoring communities for low or no-notice response where scientifically tested or clinically verified practice evidence is limited.
A history of high-power laser research and development in the United Kingdom
- Part of
- Colin N. Danson, Malcolm White, John R. M. Barr, Thomas Bett, Peter Blyth, David Bowley, Ceri Brenner, Robert J. Collins, Neal Croxford, A. E. Bucker Dangor, Laurence Devereux, Peter E. Dyer, Anthony Dymoke-Bradshaw, Christopher B. Edwards, Paul Ewart, Allister I. Ferguson, John M. Girkin, Denis R. Hall, David C. Hanna, Wayne Harris, David I. Hillier, Christopher J. Hooker, Simon M. Hooker, Nicholas Hopps, Janet Hull, David Hunt, Dino A. Jaroszynski, Mark Kempenaars, Helmut Kessler, Sir Peter L. Knight, Steve Knight, Adrian Knowles, Ciaran L. S. Lewis, Ken S. Lipton, Abby Littlechild, John Littlechild, Peter Maggs, Graeme P. A. Malcolm, OBE, Stuart P. D. Mangles, William Martin, Paul McKenna, Richard O. Moore, Clive Morrison, Zulfikar Najmudin, David Neely, Geoff H. C. New, Michael J. Norman, Ted Paine, Anthony W. Parker, Rory R. Penman, Geoff J. Pert, Chris Pietraszewski, Andrew Randewich, Nadeem H. Rizvi, Nigel Seddon, MBE, Zheng-Ming Sheng, David Slater, Roland A. Smith, Christopher Spindloe, Roy Taylor, Gary Thomas, John W. G. Tisch, Justin S. Wark, Colin Webb, S. Mark Wiggins, Dave Willford, Trevor Winstone
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- Journal:
- High Power Laser Science and Engineering / Volume 9 / 2021
- Published online by Cambridge University Press:
- 27 April 2021, e18
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The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.
The effect of an unsteady flow incident on an array of circular cylinders
- C. A. Klettner, I. Eames, J. C. R. Hunt
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- Journal:
- Journal of Fluid Mechanics / Volume 872 / 10 August 2019
- Published online by Cambridge University Press:
- 13 June 2019, pp. 560-593
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In this paper we investigate the effect of an inhomogeneous and unsteady velocity field incident on an array of rigid circular cylinders arranged within a circular perimeter (diameter $D_{G}$) of varying solid fraction $\unicode[STIX]{x1D719}$, where the unsteady flow is generated by placing a cylinder (diameter $D_{G}$) upwind of the array. Unsteady two-dimensional viscous simulations at a moderate Reynolds number ($Re=2100$) and also, as a means of extrapolating to a flow with a very high Reynolds number, inviscid rapid distortion theory (RDT) calculations were carried out. These novel RDT calculations required the circulation around each cylinder to be zero which was enforced using an iterative method. The two main differences which were highlighted was that the RDT calculations indicated that the tangential velocity component is amplified, both, at the front and sides of the array. For the unsteady viscous simulations this result did not occur as the two-dimensional vortices (of similar size to the array) are deflected away from the boundary and do not penetrate into the boundary layer. Secondly, the amplification is greater for the RDT calculations as for the unsteady finite Reynolds number calculations. For the two highest solid fraction arrays, the mean flow field has two recirculation regions in the near wake of the array, with closed streamlines that penetrate into the array which will have important implications for scalar transport. The increased bleed through the array at the lower solid fraction results in this recirculation region being displaced further downstream. The effect of inviscid blocking and viscous drag on the upstream streamwise velocity and strain field is investigated as it directly influences the ability of the large coherent structures to penetrate into the array and the subsequent forces exerted on the cylinders in the array. The average total force on the array was found to increase monotonically with increasing solid fraction. For high solid fraction $\unicode[STIX]{x1D719}$, although the fluctuating forces on the individual cylinders is lower than for low $\unicode[STIX]{x1D719}$, these forces are more correlated due to the proximity of the cylinders. The result is that for mid to high solid fraction arrays the fluctuating force on the array is insensitive to $\unicode[STIX]{x1D719}$. For low $\unicode[STIX]{x1D719}$, where the interaction of the cylinders is weak, the force statistics on the individual cylinders can be accurately estimated from the local slip velocity that occurs if the cylinders were removed.
2388 Utilizing a reviewer database to facilitate integration of an investigator-focused translational research and career development program across the state of Indiana
- R. L. Coffee, Jr., Julie Driscol, Tammy J. Saydyk, Anantha Shekhar, Scott C. Denne, Joe D. Hunt
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- Journal:
- Journal of Clinical and Translational Science / Volume 2 / Issue S1 / June 2018
- Published online by Cambridge University Press:
- 21 November 2018, pp. 62-63
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OBJECTIVES/SPECIFIC AIMS: The Indiana CTSI is investigating innovative approaches to integrate resources that will enrich scientific investigators. Our goals are to enhance the availability and communication among CTSI resources, for example internal funding, and to expand existing mentorship. METHODS/STUDY POPULATION: Developed a reviewer database that serves to streamline reviewer identification, decrease reviewer fatigue, and promote collaboration among disciplines. We started with a pool of NIH-funded investigators from across the Indiana CTSI core institutions and merged this list with previous CTSI reviewers and internal funding awardees. To expand this list, names and expertise from new faculty hires were added. RESULTS/ANTICIPATED RESULTS: Though this tool is relatively new, we have already observed an increase in junior faculty awareness and engagement with the CTSI. This database allows for increased opportunities of junior faculty to serve as reviewers and to refine grant writing skills and provides a platform for networking and collaborating across disciplines. It also allows for increased integration of programs with a shared reviewer database and promotes grant review standardization. DISCUSSION/SIGNIFICANCE OF IMPACT: Our database utilization seeks to decrease the time for junior faculty to obtain their first extramural grant, to enhance promotion and tenure packages, strengthen integration among CTSI programs, increase interactions between clinical and basic science investigators, and promote team science.
The scaling of straining motions in homogeneous isotropic turbulence
- G. E. Elsinga, T. Ishihara, M. V. Goudar, C. B. da Silva, J. C. R. Hunt
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- Journal:
- Journal of Fluid Mechanics / Volume 829 / 25 October 2017
- Published online by Cambridge University Press:
- 14 September 2017, pp. 31-64
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The scaling of turbulent motions is investigated by considering the flow in the eigenframe of the local strain-rate tensor. The flow patterns in this frame of reference are evaluated using existing direct numerical simulations of homogeneous isotropic turbulence over a Reynolds number range from $Re_{\unicode[STIX]{x1D706}}=34.6$ up to 1131, and also with reference to data for inhomogeneous, anisotropic wall turbulence. The average flow in the eigenframe reveals a shear layer structure containing tube-like vortices and a dissipation sheet, whose dimensions scale with the Kolmogorov length scale, $\unicode[STIX]{x1D702}$. The vorticity stretching motions scale with the Taylor length scale, $\unicode[STIX]{x1D706}_{T}$, while the flow outside the shear layer scales with the integral length scale, $L$. Furthermore, the spatial organization of the vortices and the dissipation sheet defines a characteristic small-scale structure. The overall size of this characteristic small-scale structure is $120\unicode[STIX]{x1D702}$ in all directions based on the coherence length of the vorticity. This is considerably larger than the typical size of individual vortices, and reflects the importance of spatial organization at the small scales. Comparing the overall size of the characteristic small-scale structure with the largest flow scales and the vorticity stretching motions on the scale of $4\unicode[STIX]{x1D706}_{T}$ shows that transitions in flow structure occur where $Re_{\unicode[STIX]{x1D706}}\approx 45$ and 250. Below these respective transitional Reynolds numbers, the small-scale motions and the vorticity stretching motions are progressively less well developed. Scale interactions are examined by decomposing the average shear layer into a local flow, which is induced by the shear layer vorticity, and a non-local flow, which represents the environment of the characteristic small-scale structure. The non-local strain is $4\unicode[STIX]{x1D706}_{T}$ in width and height, which is consistent with observations in high Reynolds number flow of a $4\unicode[STIX]{x1D706}_{T}$ wide instantaneous shear layer with many $\unicode[STIX]{x1D702}$-scale vortical structures inside (Ishihara et al., Flow Turbul. Combust., vol. 91, 2013, pp. 895–929). In the average shear layer, vorticity aligns with the intermediate principal strain at small scales, while it aligns with the most stretching principal strain at larger scales, consistent with instantaneous turbulence. The length scale at which the alignment changes depends on the Reynolds number. When conditioning the flow in the eigenframe on extreme dissipation, the velocity is strongly affected over large distances. Moreover, the associated peak velocity remains Reynolds number dependent when normalized by the Kolmogorov velocity scale. It signifies that extreme dissipation is not simply a small-scale property, but is associated with large scales at the same time.
The Parkes-MIT-NRAO Southern Sky Survey at 4850 MHz
- M. Griffith, A. E. Wright, A. J. Hunt, E. Troup, R. D. Ekers, P. Buckett, D. J. Cooke, G. Freeman, J. Glowacki, D. Jennings, U. Knop, B. Lam, I. McGovern, D. McConnell, R. P. Norris, R. Otrupcek, R. Twardy, T. Williams, G. Behrens, C. Chestnut, B. F. Burke, A. Fletcher, K. S. Russell, A. Savage, J. Lim, A. E. Vaughan, S. Côté, M. Anderson, A. Hons, G. L. White, S. Amy, A. Burgess, S. Chan, L. Cram, A. Gray, W. Walsh, D. Campbell-Wilson, V. McIntyre, P. Randall, M. Suters, W. J. Zealey
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- Publications of the Astronomical Society of Australia / Volume 9 / Issue 2 / 1991
- Published online by Cambridge University Press:
- 25 April 2016, pp. 243-245
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During 1990 we surveyed the southern sky using a multi-beam receiver at frequencies of 4850 and 843 MHz. The half-power beamwidths were 4 and 25 arcmin respectively. The finished surveys cover the declination range between +10 and −90 degrees declination, essentially complete in right ascension, an area of 7.30 steradians. Preliminary analysis of the 4850 MHz data indicates that we will achieve a five sigma flux density limit of about 30 mJy. We estimate that we will find between 80 000 and 90 000 new sources above this limit. This is a revised version of the paper presented at the Regional Meeting by the first four authors; the surveys now have been completed.
Contributors
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- By Francesco Acerbi, Ayca Akgoz, Matthew R. Amans, Ramsey Ashour, Mohammed Ali Aziz-Sultan, H. Hunt Batjer, Donnie Bell, Bernard R. Bendok, Giovanni Broggi, Morgan Broggi, Charles A. Bruno, Steven D. Chang, In Sup Choi, Omar Choudhri, Douglas J. Cook, William P. Dillon, Peter Dirks, Rose Du, Travis M. Dumont, Tarek Y. El Ahmadieh, Najib E. El Tecle, Mohamed Samy Elhammady, Paolo Ferroli, Alana M. Flexman, John C. Flickinger, Kai U. Frerichs, Sasikhan Geibprasert, Adrian W. Gelb, Y. Pierre Gobin, Bradley A. Gross, Seunggu J. Han, Tomoki Hashimoto, Juha Hernesniemi, Roberto C. Heros, Steven W. Hetts, Randall T. Higashida, Joshua A. Hirsch, Nikolai J. Hopf, L. Nelson Hopkins, Maziyar A. Kalani, M. Yashar S. Kalani, Hideyuki Kano, Syed Aftab Karim, Robert M. Koffie, Douglas S. Kondziolka, Timo Krings, Aki Laakso, Giuseppe Lanzino, Michael T. Lawton, Elad I. Levy, L. Dade Lunsford, Adel M. Malek, Michael P. Marks, George A. C. Mendes, Philip M. Meyers, Jacques Morcos, Nitin Mukerji, Christian Musahl, Ludmila Pawlikowska, Matthew B. Potts, Ross Puffer, James D. Rabinov, Jonathan J. Russin, Mina G. Safain, Duke Samson, Marco Schiariti, R. Michael Scott, Jason P. Sheehan, Paul Singh, Edward R. Smith, Scott G. Soltys, Robert F. Spetzler, Gary K. Steinberg, Philip E. Stieg, Hua Su, Karel terBrugge, Kiron Thomas, Tarik Tihan, Babu Welch, Jonathan White, H. Richard Winn, Chun-Po Yen, Jacky T. Yeung, Byron Yip, Samer G. Zammar
- Edited by Robert F. Spetzler, Douglas S. Kondziolka, Randall T. Higashida, University of California, San Francisco, M. Yashar S. Kalani
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- Book:
- Comprehensive Management of Arteriovenous Malformations of the Brain and Spine
- Published online:
- 05 January 2015
- Print publication:
- 08 January 2015, pp x-xiv
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Contributors
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- By Naila A. Ahmad, Dua M. Anderson, Jennifer Aunspaugh, Sabrina T. Bent, Adam Broussard, Staci Cameron, Rahul Dasgupta, Ravinder Devgun, Ofer N. Eytan, Sean H. Flack, Terry G. Fletcher, Charles James Fox, Mary Elise Fox, Scott Friedman, Louise K. Furukawa, Sonja Gennuso, Stanley M. Hall, Hani Hanna, Jacob Hummel, James E. Hunt, Ranu Jain, Joe R. Jansen, Deepa Kattail, Alan David Kaye, David J. Krodel, Gregory J. Latham, Sungeun Lee, Michael G. Levitzky, Alexander Y. Lin, Carl Lo, Hoa N. Luu, Camila Lyon, Kelly A. Machovec, Lizabeth D. Martin, Maria Matuszczak, Patrick S. McCarty, Brenda C. McClain, J. Grant McFadyen, Helen Nazareth, Dolores B. Njoku, Christina M. Pabelick, Shannon M. Peters, Amit Prabhakar, Michael Richards, Kasia Rubin, Joel A. Saltzman, Lisgelia Santana, Gabriel Sarah, Katherine Stammen, John Stork, Kim M. Strupp, Lalitha V. Sundararaman, Rosalie F. Tassone, Douglas R. Thompson, Nicole C. P. Thompson, Paul A. Tripi, Jacqueline L. Tutiven, Navyugjit Virk, Stacey Watt, B. Craig Weldon, Maria Zestus
- Edited by Alan David Kaye, Louisiana State University, Charles James Fox, Tulane University School of Medicine, Louisiana, James H. Diaz, Louisiana State University
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- Book:
- Essentials of Pediatric Anesthesiology
- Published online:
- 05 November 2014
- Print publication:
- 16 October 2014, pp ix-xii
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- By Jane Balme, Graeme Barker, James Blinkhorn, Sandra Bowdler, Christopher Clarkson, Richard Cosgrove, Iain Davidson, Robin Dennell, Anne Ford, Natalie R. Franklin, Ian Gilligan, Huw S. Groucutt, Phillip J. Habgood, Chris Hunt, Michelle C. Langley, Armand Salvador B. Mijares, M. J. Morwood, Sue O’Connor, Stephen Oppenheimer, Alfred F. Pawlik, Michael D. Petraglia, Anne Pike-Tay, Philip J. Piper, Martin Porr, Ryan J. Rabett, Wil Roebroeks, Glenn R. Summerhayes
- Edited by Robin Dennell, University of Exeter, Martin Porr, University of Western Australia, Perth
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- Book:
- Southern Asia, Australia, and the Search for Human Origins
- Published online:
- 05 February 2014
- Print publication:
- 24 February 2014, pp xi-xvi
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- By Anthony Atala, Karl W. Broman, Irene Cervelló, David K. Gardner, Caroline E. Gargett, Nicolás Garrido, Ellen Goossens, Jennifer R. Gruhn, Alexandra J. Harvey, Terry J. Hassold, Patricia A. Hunt, Orkan Ilbay, Irina Klimanskaya, Tippi C. MacKenzie, Ana M. Martínez-Arroyo, Jose V. Medrano, Heidi Mertes, Marcos Meseguer, Sergio Mora, Sean V. Murphy, Hong P.T. Nguyen, Amar Nijagal, Takehiko Ogawa, Guido Pennings, Joy Rathjen, Angel Raya, Renee A. Reijo Pera, Rocío Rivera, Emre Seli, Carlos Simón, Herman Tournaye, Agustín G. Zapata
- Edited by Carlos Simón, Antonio Pellicer, Renee Reijo Pera
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- Book:
- Stem Cells in Reproductive Medicine
- Published online:
- 05 July 2013
- Print publication:
- 04 July 2013, pp vii-viii
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Heritability estimates of methane emissions from sheep
- C. S. Pinares-Patiño, S. M. Hickey, E. A. Young, K. G. Dodds, S. MacLean, G. Molano, E. Sandoval, H. Kjestrup, R. Harland, C. Hunt, N. K. Pickering, J. C. McEwan
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The objective of this study was to determine the genetic parameters of methane (CH4) emissions and their genetic correlations with key production traits. The trial measured the CH4 emissions, at 5-min intervals, from 1225 sheep placed in respiration chambers for 2 days, with repeat measurements 2 weeks later for another 2 days. They were fed in the chambers, based on live weight, a pelleted lucerne ration at 2.0 times estimated maintenance requirements. Methane outputs were calculated for g CH4/day and g CH4/kg dry matter intake (DMI) for each of the 4 days. Single trait models were used to obtain estimates of heritability and repeatability. Heritability of g CH4/day was 0.29 ± 0.05, and for g CH4/kg DMI 0.13 ± 0.03. Repeatability between measurements 14 days apart were 0.55 ± 0.02 and 0.26 ± 0.02, for the two traits. The genetic and phenotypic correlations of CH4 outputs with various production traits (weaning weight, live weight at 8 months of age, dag score, muscle depth and fleece weight at 12 months of age) measured in the first year of life, were estimated using bivariate models. With the exception of fleece weight, correlations were weak and not significantly different from zero for the g CH4/kg DMI trait. For fleece weight the phenotypic and genetic correlation estimates were −0.08 ± 0.03 and −0.32 ± 0.11 suggesting a low economically favourable relationship. These results indicate that there is genetic variation between animals for CH4 emission traits even after adjustment for feed intake and that these traits are repeatable. Current work includes the establishment of selection lines from these animals to investigate the physiological, microbial and anatomical changes, coupled with investigations into shorter and alternative CH4 emission measurement and breeding value estimation techniques; including genomic selection.
Adapting a PET Imaging Agent for Correlative Microscopy of Meningiomas and Other Intracranial Tumors
- W. Lingle, V. Negron, G. Johnson, J. Parasi, M. Nathan, C. Hunt, P. Peller, S. Broski, A. Fauq, R. Petersen, V. Lowe
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- Journal:
- Microscopy and Microanalysis / Volume 18 / Issue S2 / July 2012
- Published online by Cambridge University Press:
- 23 November 2012, pp. 178-179
- Print publication:
- July 2012
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Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.
Psychiatric in-patient care and suicide in England, 1997 to 2008: a longitudinal study
- N. Kapur, I. M. Hunt, K. Windfuhr, C. Rodway, R. Webb, M. S. Rahman, J. Shaw, L. Appleby
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- Journal:
- Psychological Medicine / Volume 43 / Issue 1 / January 2013
- Published online by Cambridge University Press:
- 17 May 2012, pp. 61-71
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Background
Psychiatric in-patients are at high risk of suicide. Recent reductions in bed numbers in many countries may have affected this risk but few studies have specifically investigated temporal trends. We aimed to explore trends in psychiatric in-patient suicide over time.
MethodA prospective study of all patients admitted to National Health Service (NHS) in-patient psychiatric care in England (1997–2008). Suicide rates were determined using National Confidential Inquiry and Hospital Episode Statistics (HES) data.
ResultsOver the study period there were 1942 psychiatric in-patient suicides. Between the first 2 years of the study (1997, 1998) and the last 2 years (2007, 2008) the rate of in-patient suicide fell by nearly one-third from 2.45 to 1.68 per 100 000 bed days. This fall in rate was observed for males and females, across ethnicities and diagnoses. It was most marked for patients aged 15–44 years. Rates also fell for the most common suicide methods, particularly suicide by hanging on the ward (a 59% reduction). Although the number of post-discharge suicides fell, the rate of post-discharge suicide may have increased by 19%. The number of suicide deaths in those under the care of crisis resolution/home treatment teams has increased in recent years to approximately 160 annually.
ConclusionsThe rate of suicide among psychiatric in-patients in England has fallen considerably. Possible explanations include falling general population rates, changes in the at-risk population or improved in-patient safety. However, a transfer of risk to the period after discharge or other clinical settings such as crisis resolution teams cannot be ruled out.
A nursery site of the golden skate (Rajiformes: Rajidae: Bathyraja smirnovi) on the Shiribeshi Seamount, Sea of Japan
- James C. Hunt, Dhugal J. Lindsay, Raushan R. Shahalemi
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- Journal:
- Marine Biodiversity Records / Volume 4 / December 2011
- Published online by Cambridge University Press:
- 29 September 2011, e70
- Print publication:
- December 2011
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During a series of submersible surveys of the Shiribeshi Seamount, northern Sea of Japan, by the remotely-operated vehicle (ROV) ‘Dolphin 3K’ and the human-occupied vehicle (HOV) ‘Shinkai 2000’ in July 2001, dense patches of golden skate eggs were observed. Given the lack of information for this species, an analysis was performed to estimate the abundance of the eggs and to ascertain if any patterns could be determined from the distribution of eggs on the sea-floor as recorded by the ROV and HOV video cameras. Eggs, including some with viable embryos, were found on only one of four ROV benthic transect surveys and one crewed submersible dive in the same location. The site where eggs were laid was relatively small and appeared to have been revisited through time. This work is part of an ongoing collaborative effort between East Stroudsburg University and the Marine Biodiversity Research Programme at the Japan Agency for Marine–Earth Science and Technology to characterize the midwater and benthic deep-sea faunas around Japan.
Contributors
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- By Phillip L. Ackerman, Soon Ang, Susan M. Barnett, G. David Batty, Anna S. Beninger, Jillian Brass, Meghan M. Burke, Nancy Cantor, Priyanka B. Carr, David R. Caruso, Stephen J. Ceci, Lillia Cherkasskiy, Joanna Christodoulou, Andrew R. A. Conway, Christine E. Daley, Janet E. Davidson, Jim Davies, Katie Davis, Ian J. Deary, Colin G. DeYoung, Ron Dumont, Carol S. Dweck, Linn Van Dyne, Pascale M. J. Engel de Abreu, Joseph F. Fagan, David Henry Feldman, Kurt W. Fischer, Marisa H. Fisher, James R. Flynn, Liane Gabora, Howard Gardner, Glenn Geher, Sarah J. Getz, Judith Glück, Ashok K. Goel, Megan M. Griffin, Elena L. Grigorenko, Richard J. Haier, Diane F. Halpern, Christopher Hertzog, Robert M. Hodapp, Earl Hunt, Alan S. Kaufman, James C. Kaufman, Scott Barry Kaufman, Iris A. Kemp, John F. Kihlstrom, Joni M. Lakin, Christina S. Lee, David F. Lohman, N. J. Mackintosh, Brooke Macnamara, Samuel D. Mandelman, John D. Mayer, Richard E. Mayer, Martha J. Morelock, Ted Nettelbeck, Raymond S. Nickerson, Weihua Niu, Anthony J. Onwuegbuzie, Jonathan A. Plucker, Sally M. Reis, Joseph S. Renzulli, Heiner Rindermann, L. Todd Rose, Anne Russon, Peter Salovey, Scott Seider, Ellen L. Short, Keith E. Stanovich, Ursula M. Staudinger, Robert J. Sternberg, Carli A. Straight, Lisa A. Suzuki, Mei Ling Tan, Maggie E. Toplak, Susana Urbina, Richard K. Wagner, Richard F. West, Wendy M. Williams, John O. Willis, Thomas R. Zentall
- Edited by Robert J. Sternberg, Oklahoma State University, Scott Barry Kaufman, New York University
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- Book:
- The Cambridge Handbook of Intelligence
- Published online:
- 05 June 2012
- Print publication:
- 30 May 2011, pp xi-xiv
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Viscous coupling of shear-free turbulence across nearly flat fluid interfaces
- J. C. R. HUNT, D. D. STRETCH, S. E. BELCHER
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- Journal:
- Journal of Fluid Mechanics / Volume 671 / 25 March 2011
- Published online by Cambridge University Press:
- 24 February 2011, pp. 96-120
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The interactions between shear-free turbulence in two regions (denoted as + and − on either side of a nearly flat horizontal interface are shown here to be controlled by several mechanisms, which depend on the magnitudes of the ratios of the densities, ρ+/ρ−, and kinematic viscosities of the fluids, μ+/μ−, and the root mean square (r.m.s.) velocities of the turbulence, u0+/u0−, above and below the interface. This study focuses on gas–liquid interfaces so that ρ+/ρ− ≪ 1 and also on where turbulence is generated either above or below the interface so that u0+/u0− is either very large or very small. It is assumed that vertical buoyancy forces across the interface are much larger than internal forces so that the interface is nearly flat, and coupling between turbulence on either side of the interface is determined by viscous stresses. A formal linearized rapid-distortion analysis with viscous effects is developed by extending the previous study by Hunt & Graham (J. Fluid Mech., vol. 84, 1978, pp. 209–235) of shear-free turbulence near rigid plane boundaries. The physical processes accounted for in our model include both the blocking effect of the interface on normal components of the turbulence and the viscous coupling of the horizontal field across thin interfacial viscous boundary layers. The horizontal divergence in the perturbation velocity field in the viscous layer drives weak inviscid irrotational velocity fluctuations outside the viscous boundary layers in a mechanism analogous to Ekman pumping. The analysis shows the following. (i) The blocking effects are similar to those near rigid boundaries on each side of the interface, but through the action of the thin viscous layers above and below the interface, the horizontal and vertical velocity components differ from those near a rigid surface and are correlated or anti-correlated respectively. (ii) Because of the growth of the viscous layers on either side of the interface, the ratio uI/u0, where uI is the r.m.s. of the interfacial velocity fluctuations and u0 the r.m.s. of the homogeneous turbulence far from the interface, does not vary with time. If the turbulence is driven in the lower layer with ρ+/ρ− ≪ 1 and u0+/u0− ≪ 1, then uI/u0− ~ 1 when Re (=u0−L−/ν−) ≫ 1 and R = (ρ−/ρ+)(v−/v+)1/2 ≫ 1. If the turbulence is driven in the upper layer with ρ+/ρ− ≪ 1 and u0+/u0− ≫ 1, then uI/u0+ ~ 1/(1 + R). (iii) Nonlinear effects become significant over periods greater than Lagrangian time scales. When turbulence is generated in the lower layer, and the Reynolds number is high enough, motions in the upper viscous layer are turbulent. The horizontal vorticity tends to decrease, and the vertical vorticity of the eddies dominates their asymptotic structure. When turbulence is generated in the upper layer, and the Reynolds number is less than about 106–107, the fluctuations in the viscous layer do not become turbulent. Nonlinear processes at the interface increase the ratio uI/u0+ for sheared or shear-free turbulence in the gas above its linear value of uI/u0+ ~ 1/(1 + R) to (ρ+/ρ−)1/2 ~ 1/30 for air–water interfaces. This estimate agrees with the direct numerical simulation results from Lombardi, De Angelis & Bannerjee (Phys. Fluids, vol. 8, no. 6, 1996, pp. 1643–1665). Because the linear viscous–inertial coupling mechanism is still significant, the eddy motions on either side of the interface have a similar horizontal structure, although their vertical structure differs.
Distorted turbulence and secondary flow near right-angled plates
- K. NAGATA, J. C. R. HUNT, Y. SAKAI, H. WONG
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- Journal:
- Journal of Fluid Mechanics / Volume 668 / 10 February 2011
- Published online by Cambridge University Press:
- 16 December 2010, pp. 446-479
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In many turbulent flows near obstacles or in ducts, the turbulence is inhomogeneous in two directions perpendicular to the main flow direction. In convective flows, there may initially be no mean motion. In both types of flow the gradients of Reynolds stresses drive mean motions in directions of inhomogeneity. Using the method of rapid distortion theory developed by Hunt & Graham (J. Fluid Mech., vol. 84, 1978, p. 209), we analyse these gradients where homogeneous isotropic turbulence is impinging onto two semi-infinite flat rigid surfaces intersecting at right angles. The mean velocity is assumed to be uniform (i.e. the surfaces move at free-stream velocity, or the boundary layers are very thin). The inhomogeneous spectra, variances and Reynolds-stress gradients are evaluated. For isotropic free-stream turbulence with mean square velocity u2∞1, the mean square velocity fluctuation at a high Reynolds number in the corner is u21(X, 0, 0) = 2.121u2∞1, independent of the form of the spectrum. This is explained by estimating how the free-stream eddies are blocked by the two walls. The gradients of Reynolds stresses force a mean secondary flow to develop; its direction is into the corner, and its magnitude at time t is of order tu2∞1/L∞, where L∞ is the integral scale. These results are tested in a wind tunnel experiment. A turbulence-generating grid installed at the entrance to the test section generates nearly isotropic, grid-generated turbulence. A corner plate with faces parallel to the mean flow and sharp edges is placed downstream of the grid so that shear-free turbulence impinges onto the corner plate. The turbulent Reynolds number based on , is 1400 at the leading edge of the plate. A hot-wire anemometry is used to measure instantaneous velocities. The experimental results are consistent with the rapid distortion theory estimates for the variances and the secondary mean motion, which is in the same direction and has the same order of magnitude as Prandtl's analysis of shear-driven secondary flow (of the second kind). We conclude that the blocking mechanism adds to the shear effects and has a significant and sometimes dominant contribution to the crossflows wherever it acts in two non-parallel directions, such as convection in a corner. Consequently, mean transport into corners occurs for most kinds of distorted flow with weak viscous stresses, which has many engineering and environmental implications. There are also implications for the chaotic nature of many confined flows near corners.
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- By Saleh H. Alwasel, Susan P. Bagby, David J. P Barker, Richard Boyd, Robert Boyd, Graham Burdge, Graham J Burton, Anthony M Carter, Irene Cetin, Zoe Cole, Cyrus Cooper, Hilary Critchley, Elaine Dennison, Susie Earl, Johan G Eriksson, Caroline H. D Fall, Anne C. Ferguson-Smith, Tom P. Fleming, Alison J. Forhead, Abigail L. Fowden, Dino Giussani, Laura Goodfellow, Nicholas Harvey, Christopher Holroyd, Joan Hunt, Alan A. Jackson, Thomas Jansson, Eric Jauniaux, Rosalind John, Eero Kajantie, Michelle Lampl, Karen Lillycrop, Charlie Loke, Samantha Louey, Per Magnus, Ashley Moffett, Lorna G. Moore, Terry Morgan, Clive Osmond, Perrie F. O'Tierney, Robert Pijnenborg, Lucilla Poston, Theresa L. Powell, Elizabeth J. Radford, Tessa J. Roseboom, Amanda Sferruzzi-Perri, Colin P. Sibley, Gordon C. S. Smith, Emanuela Taricco, Kent Thornburg, Benjamin Tycko, Owen R. Vaughan, Lisbeth Vercruysse
- Edited by Graham J. Burton, David J. P. Barker, Ashley Moffett, Kent Thornburg
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- Book:
- The Placenta and Human Developmental Programming
- Published online:
- 04 February 2011
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- 16 December 2010, pp vii-x
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. 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Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. 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Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. Lotz, Andrew Louth, Robin W. Lovin, William Luis, Frank D. Macchia, Diarmaid N. J. MacCulloch, Kirk R. MacGregor, Marjory A. MacLean, Donald MacLeod, Tomas S. Maddela, Inge Mager, Laurenti Magesa, David G. Maillu, Fortunato Mallimaci, Philip Mamalakis, Kä Mana, Ukachukwu Chris Manus, Herbert Robinson Marbury, Reuel Norman Marigza, Jacqueline Mariña, Antti Marjanen, Luiz C. L. Marques, Madipoane Masenya (ngwan'a Mphahlele), Caleb J. D. Maskell, Steve Mason, Thomas Massaro, Fernando Matamoros Ponce, András Máté-Tóth, Odair Pedroso Mateus, Dinis Matsolo, Fumitaka Matsuoka, John D'Arcy May, Yelena Mazour-Matusevich, Theodore Mbazumutima, John S. McClure, Christian McConnell, Lee Martin McDonald, Gary B. McGee, Thomas McGowan, Alister E. McGrath, Richard J. McGregor, John A. McGuckin, Maud Burnett McInerney, Elsie Anne McKee, Mary B. McKinley, James F. McMillan, Ernan McMullin, Kathleen E. McVey, M. Douglas Meeks, Monica Jyotsna Melanchthon, Ilie Melniciuc-Puica, Everett Mendoza, Raymond A. Mentzer, William W. Menzies, Ina Merdjanova, Franziska Metzger, Constant J. Mews, Marvin Meyer, Carol Meyers, Vasile Mihoc, Gunner Bjerg Mikkelsen, Maria Inêz de Castro Millen, Clyde Lee Miller, Bonnie J. Miller-McLemore, Alexander Mirkovic, Paul Misner, Nozomu Miyahira, R. W. L. Moberly, Gerald Moede, Aloo Osotsi Mojola, Sunanda Mongia, Rebeca Montemayor, James Moore, Roger E. Moore, Craig E. Morrison O.Carm, Jeffry H. Morrison, Keith Morrison, Wilson J. Moses, Tefetso Henry Mothibe, Mokgethi Motlhabi, Fulata Moyo, Henry Mugabe, Jesse Ndwiga Kanyua Mugambi, Peggy Mulambya-Kabonde, Robert Bruce Mullin, Pamela Mullins Reaves, Saskia Murk Jansen, Heleen L. Murre-Van den Berg, Augustine Musopole, Isaac M. T. Mwase, Philomena Mwaura, Cecilia Nahnfeldt, Anne Nasimiyu Wasike, Carmiña Navia Velasco, Thulani Ndlazi, Alexander Negrov, James B. Nelson, David G. Newcombe, Carol Newsom, Helen J. 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Van Bavel, Steven Vanderputten, Peter Van der Veer, Huub Van de Sandt, Louis Van Tongeren, Luke A. Veronis, Noel Villalba, Ramón Vinke, Tim Vivian, David Voas, Elena Volkova, Katharina von Kellenbach, Elina Vuola, Timothy Wadkins, Elaine M. Wainwright, Randi Jones Walker, Dewey D. Wallace, Jerry Walls, Michael J. Walsh, Philip Walters, Janet Walton, Jonathan L. Walton, Wang Xiaochao, Patricia A. Ward, David Harrington Watt, Herold D. Weiss, Laurence L. Welborn, Sharon D. Welch, Timothy Wengert, Traci C. West, Merold Westphal, David Wetherell, Barbara Wheeler, Carolinne White, Jean-Paul Wiest, Frans Wijsen, Terry L. Wilder, Felix Wilfred, Rebecca Wilkin, Daniel H. Williams, D. Newell Williams, Michael A. Williams, Vincent L. Wimbush, Gabriele Winkler, Anders Winroth, Lauri Emílio Wirth, James A. Wiseman, Ebba Witt-Brattström, Teofil Wojciechowski, John Wolffe, Kenman L. Wong, Wong Wai Ching, Linda Woodhead, Wendy M. Wright, Rose Wu, Keith E. Yandell, Gale A. Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- Book:
- The Cambridge Dictionary of Christianity
- Published online:
- 05 August 2012
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- 20 September 2010, pp xi-xliv
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The unidirectional emptying box
- C. J. COFFEY, G. R. HUNT
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- Journal:
- Journal of Fluid Mechanics / Volume 660 / 10 October 2010
- Published online by Cambridge University Press:
- 01 September 2010, pp. 456-474
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A theoretical description of the turbulent mixing within and the draining of a dense fluid layer from a box connected to a uniform density, quiescent environment through openings in the top and the base of the box is presented in this paper. This is an extension of the draining model developed by Linden et al. (Annu. Rev. Fluid Mech. vol. 31, 1990, pp. 201–238) and includes terms that describe localized mixing within the emptying box at the density interface. Mixing is induced by a turbulent flow of replacement fluid into the box and as a consequence we predict, and observe in complementary experiments, the development of a three-layer stratification. Based on the data collated from previous researchers, three distinct formulations for entrainment fluxes across density interfaces are used to account for this localized mixing. The model was then solved numerically for the three mixing formulations. Analytical solutions were developed for one formulation directly and for a second on assuming that localized mixing is relatively weak though still significant in redistributing buoyancy on the timescale of the draining process. Comparisons between our theoretical predictions and the experimental data, which we have collected on the developing layer depths and their densities show good agreement. The differences in predictions between the three mixing formulations suggest that the normalized flux turbulently entrained across a density interface tends to a constant value for large values of a Froude number FrT, based on conditions of the inflow through the top of the box, and scales as the cube of FrT for small values of FrT. The upper limit on the rate of entrainment into the mixed layer results in a minimum time (tD) to remove the original dense layer. Using our analytical solutions, we bound this time and show that 0.2tE ≲ tD ≲ tE, i.e. the original dense layer may be depleted up to five times more rapidly than when there is no internal mixing and the box empties in a time tE.