21 results
The association between area-level residential instability and gray matter volume changes
- B. Ku, J. Addington, C. Bearden, K. Cadenhead, T. Cannon, M. Compton, B. Cornblatt, B. Druss, M. Keshavan, D. Mathalon, T. Mcglashan, D. Perkins, L. Seidman, W. Stone, M. Tsuang, S. Woods, E. Walker
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- Journal:
- European Psychiatry / Volume 65 / Issue S1 / June 2022
- Published online by Cambridge University Press:
- 01 September 2022, p. S787
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Introduction
Area-level residential instability (ARI), an index of social fragmentation, has been shown to explain the association between urbanicity and psychosis. Urban upbringing has been shown to be associated with decreased gray matter volumes (GMV)s of brain regions corresponding to the right caudal middle frontal gyrus (CMFG) and rostral anterior cingulate cortex (rACC).
ObjectivesWe hypothesize that greater ARI will be associated with reduced right posterior CMFG and rACC GMVs.
MethodsData were collected at baseline as part of the North American Prodrome Longitudinal Study. Counties where participants resided during childhood were geographically coded using the US Censuses to area-level factors. ARI was defined as the percentage of residents living in a different house five years ago. Generalized linear mixed models tested associations between ARI and GMVs.
ResultsThis study included 29 HC and 64 CHR-P individuals who were aged 12 to 24 years, had remained in their baseline residential area, and had magnetic resonance imaging scans. ARI was associated with reduced right CMFG (adjusted β = -0.258; 95% CI = -0.502 – -0.015) and right rACC volumes (adjusted β = -0.318; 95% CI = -0.612 – -0.023). The interaction terms (ARI X diagnostic group) in the prediction of both brain regions were not significant, indicating that the relationships between ARI and regional brain volumes held for both CHR-P and HCs.
ConclusionsLike urban upbringing, ARI may be an important social environmental characteristic that adversely impacts brain regions related to schizophrenia.
DisclosureNo significant relationships.
Compulsory admissions of patients with mental disorders: State of the art on ethical and legislative aspects in 40 European countries
- D. Wasserman, G. Apter, C. Baeken, S. Bailey, J. Balazs, C. Bec, P. Bienkowski, J. Bobes, M. F. Bravo Ortiz, H. Brunn, Ö. Bôke, N. Camilleri, B. Carpiniello, J. Chihai, E. Chkonia, P. Courtet, D. Cozman, M. David, G. Dom, A. Esanu, P. Falkai, W. Flannery, K. Gasparyan, G. Gerlinger, P. Gorwood, O. Gudmundsson, C. Hanon, A. Heinz, M. J. Heitor Dos Santos, A. Hedlund, F. Ismayilov, N. Ismayilov, E. T. Isometsä, L. Izakova, A. Kleinberg, T. Kurimay, S. Klæbo Reitan, D. Lecic-Tosevski, A. Lehmets, N. Lindberg, K. A. Lundblad, G. Lynch, C. Maddock, U.F. Malt, L. Martin, I. Martynikhin, N. O. Maruta, F. Matthys, R. Mazaliauskiene, G. Mihajlovic, A. Mihaljevic Peles, V. Miklavic, P. Mohr, M. Munarriz Ferrandis, M. Musalek, N. Neznanov, G. Ostorharics-Horvath, I. Pajević, A. Popova, P. Pregelj, E. Prinsen, C. Rados, A. Roig, M. Rojnic Kuzman, J. Samochowiec, N. Sartorius, Y. Savenko, O. Skugarevsky, E. Slodecki, A. Soghoyan, D. S. Stone, R. Taylor-East, E. Terauds, C. Tsopelas, C. Tudose, S. Tyano, P. Vallon, R. J. Van der Gaag, P. Varandas, L. Vavrusova, P. Voloshyn, J. Wancata, J. Wise, Z. Zemishlany, F. Öncü, S. Vahip
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- Journal:
- European Psychiatry / Volume 63 / Issue 1 / 2020
- Published online by Cambridge University Press:
- 24 August 2020, e82
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Background.
Compulsory admission procedures of patients with mental disorders vary between countries in Europe. The Ethics Committee of the European Psychiatric Association (EPA) launched a survey on involuntary admission procedures of patients with mental disorders in 40 countries to gather information from all National Psychiatric Associations that are members of the EPA to develop recommendations for improving involuntary admission processes and promote voluntary care.
Methods.The survey focused on legislation of involuntary admissions and key actors involved in the admission procedure as well as most common reasons for involuntary admissions.
Results.We analyzed the survey categorical data in themes, which highlight that both medical and legal actors are involved in involuntary admission procedures.
Conclusions.We conclude that legal reasons for compulsory admission should be reworded in order to remove stigmatization of the patient, that raising awareness about involuntary admission procedures and patient rights with both patients and family advocacy groups is paramount, that communication about procedures should be widely available in lay-language for the general population, and that training sessions and guidance should be available for legal and medical practitioners. Finally, people working in the field need to be constantly aware about the ethical challenges surrounding compulsory admissions.
Childhood trauma and cognitive functioning in individuals at clinical high risk (CHR) for psychosis
- T. Velikonja, E. Velthorst, J. Zinberg, T. D. Cannon, B. A. Cornblatt, D. O. Perkins, K. S. Cadenhead, M. T. Tsuang, J. Addington, S. W. Woods, T. McGlashan, D. H. Mathalon, W. Stone, M. Keshavan, L. Seidman, C. E. Bearden
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- Journal:
- Development and Psychopathology / Volume 33 / Issue 1 / February 2021
- Published online by Cambridge University Press:
- 21 January 2020, pp. 53-64
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Evidence suggests that early trauma may have a negative effect on cognitive functioning in individuals with psychosis, yet the relationship between childhood trauma and cognition among those at clinical high risk (CHR) for psychosis remains unexplored. Our sample consisted of 626 CHR children and 279 healthy controls who were recruited as part of the North American Prodrome Longitudinal Study 2. Childhood trauma up to the age of 16 (psychological, physical, and sexual abuse, emotional neglect, and bullying) was assessed by using the Childhood Trauma and Abuse Scale. Multiple domains of cognition were measured at baseline and at the time of psychosis conversion, using standardized assessments. In the CHR group, there was a trend for better performance in individuals who reported a history of multiple types of childhood trauma compared with those with no/one type of trauma (Cohen d = 0.16). A history of multiple trauma types was not associated with greater cognitive change in CHR converters over time. Our findings tentatively suggest there may be different mechanisms that lead to CHR states. Individuals who are at clinical high risk who have experienced multiple types of childhood trauma may have more typically developing premorbid cognitive functioning than those who reported minimal trauma do. Further research is needed to unravel the complexity of factors underlying the development of at-risk states.
Wheat and Italian ryegrass (Lolium multiflorum) competition as affected by phosphorus nutrition
- Harry T. Cralle, Tiffany B. Fojtasek, Katherine H. Carson, James M. Chandler, Travis D. Miller, Scott A. Senseman, Rodney W. Bovey, Martin J. Stone
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- Weed Science / Volume 51 / Issue 3 / June 2003
- Published online by Cambridge University Press:
- 20 January 2017, pp. 425-429
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A greenhouse experiment used a replacement series design to compare the vegetative growth 6 wk after emergence in pure cultures and mixtures of winter wheat and Italian ryegrass, with phosphorus (P) levels recommended by soil testing. The planting proportions of wheat and Italian ryegrass were 100 and 0%, 75 and 25%, 50 and 50%, 25 and 75%, and 0 and 100%, respectively. There was no alleopathic interaction between the species. Both species in all pure and mixed cultures had substantially less growth in the low-P than in the recommended P treatment. However, the relative performance of the two species differed between P treatments. In the recommended P treatment in pure culture, Italian ryegrass had more tillers and greater root weight and length than wheat. Pure culture wheat in the low-P treatment exceeded pure culture Italian ryegrass in leaf area, weights of leaves, stems, and roots, and root length. Thus, the growth of wheat was inhibited less by P deficiency than the growth of Italian ryegrass in pure culture. In the 50:50 mixture of the recommended P treatment, wheat had greater leaf, stem, and root weights than Italian ryegrass. In the 50:50 mixture of the low-P treatment, the two species were very similar in growth, except that Italian ryegrass had about three times more tillers than did wheat. Whereas P deficiency limited the growth of wheat less than Italian ryegrass in pure culture, P deficiency did not affect the relative competitiveness of Italian ryegrass as much as wheat in mixed cultures. The ability of Italian ryegrass to compete with wheat when P was limiting may result from a difference in root growth. Italian ryegrass had a greater fresh root length to fresh root weight ratio than did wheat in the low-P treatment in pure culture and in the 50:50 mixture. The greater surface area of Italian ryegrass roots likely enhanced the competitiveness of Italian ryegrass relative to wheat under P-deficit conditions. Thus, the use of the recommended P nutrition from soil testing may be a key component to diminish Italian ryegrass competition in wheat fields.
Tobacco smoking in schizophrenia: investigating the role of incentive salience
- T. P. Freeman, J. M. Stone, B. Orgaz, L. A. Noronha, S. L. Minchin, H. V. Curran
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- Psychological Medicine / Volume 44 / Issue 10 / July 2014
- Published online by Cambridge University Press:
- 01 November 2013, pp. 2189-2197
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Background
Smoking is highly prevalent in people diagnosed with schizophrenia, but the reason for this co-morbidity is currently unclear. One possible explanation is that a common abnormality underpins the development of psychosis and independently enhances the incentive motivational properties of drugs and their associated cues. This study aimed to investigate whether incentive salience attribution towards smoking cues, as assessed by attentional bias, is heightened in schizophrenia and associated with delusions and hallucinations.
MethodTwenty-two smokers diagnosed with schizophrenia and 23 control smokers were assessed for smoking-related attentional bias using a modified Stroop task. Craving, nicotine dependence, smoking behaviour and positive and negative symptoms of schizophrenia were also recorded.
ResultsBoth groups showed similar craving scores and smoking behaviour according to self-report and expired carbon monoxide (CO), although the patient group had higher nicotine dependence scores. Attentional bias, as evidenced by significant interference from smoking-related words on the modified Stroop task, was similar in both groups and correlated with CO levels. Attentional bias was positively related to severity of delusions but not hallucinations or other symptoms in the schizophrenia group.
ConclusionsThis study supports the hypothesis that the development of delusions and the incentive motivational aspects of smoking may share a common biological substrate. These findings may offer some explanation for the elevated rates of smoking and other drug use in people with psychotic illness.
The H1N1 Crisis: A Case Study of the Integration of Mental and Behavioral Health in Public Health Crises
- Betty Pfefferbaum, David Schonfeld, Brian W. Flynn, Ann E. Norwood, Daniel Dodgen, Rachel E. Kaul, Darrin Donato, Brook Stone, Lisa M. Brown, Dori B. Reissman, Gerard A. Jacobs, Stevan E. Hobfoll, Russell T. Jones, Jack Herrmann, Robert J. Ursano, Josef I. Ruzek
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- Disaster Medicine and Public Health Preparedness / Volume 6 / Issue 1 / March 2012
- Published online by Cambridge University Press:
- 08 April 2013, pp. 67-71
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In substantial numbers of affected populations, disasters adversely affect well-being and influence the development of emotional problems and dysfunctional behaviors. Nowhere is the integration of mental and behavioral health into broader public health and medical preparedness and response activities more crucial than in disasters such as the 2009-2010 H1N1 influenza pandemic. The National Biodefense Science Board, recognizing that the mental and behavioral health responses to H1N1 were vital to preserving safety and health for the country, requested that the Disaster Mental Health Subcommittee recommend actions for public health officials to prevent and mitigate adverse behavioral health outcomes during the H1N1 pandemic. The subcommittee's recommendations emphasized vulnerable populations and concentrated on interventions, education and training, and communication and messaging. The subcommittee's H1N1 activities and recommendations provide an approach and template for identifying and addressing future efforts related to newly emerging public health and medical emergencies. The many emotional and behavioral health implications of the crisis and the importance of psychological factors in determining the behavior of members of the public argue for a programmatic integration of behavioral health and science expertise in a comprehensive public health response.
(Disaster Med Public Health Preparedness. 2012;6:67–71)
The Integration of Mental and Behavioral Health Into Disaster Preparedness, Response, and Recovery
- Betty Pfefferbaum, Brian W. Flynn, David Schonfeld, Lisa M. Brown, Gerard A. Jacobs, Daniel Dodgen, Darrin Donato, Rachel E. Kaul, Brook Stone, Ann E. Norwood, Dori B. Reissman, Jack Herrmann, Stevan E. Hobfoll, Russell T. Jones, Josef I. Ruzek, Robert J. Ursano, Robert J. Taylor, David Lindley
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- Disaster Medicine and Public Health Preparedness / Volume 6 / Issue 1 / March 2012
- Published online by Cambridge University Press:
- 08 April 2013, pp. 60-66
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The close interplay between mental health and physical health makes it critical to integrate mental and behavioral health considerations into all aspects of public health and medical disaster management. Therefore, the National Biodefense Science Board (NBSB) convened the Disaster Mental Health Subcommittee to assess the progress of the US Department of Health and Human Services (HHS) in integrating mental and behavioral health into disaster and emergency preparedness and response activities. One vital opportunity to improve integration is the development of clear and directive national policy to firmly establish the role of mental and behavioral health as part of a unified public health and medical response to disasters. Integration of mental and behavioral health into disaster preparedness, response, and recovery requires it to be incorporated in assessments and services, addressed in education and training, and founded on and advanced through research. Integration must be supported in underlying policies and administration with clear lines of responsibility for formulating and implementing policy and practice.
(Disaster Med Public Health Preparedness. 2012;6:60–66)
Unstable Richtmyer–Meshkov growth of solid and liquid metals in vacuum
- W. T. Buttler, D. M. Oró, D. L. Preston, K. O. Mikaelian, F. J. Cherne, R. S. Hixson, F. G. Mariam, C. Morris, J. B. Stone, G. Terrones, D. Tupa
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- Journal of Fluid Mechanics / Volume 703 / 25 July 2012
- Published online by Cambridge University Press:
- 13 June 2012, pp. 60-84
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We present experimental results supporting physics-based ejecta model development, where our main assumption is that ejecta form as a special limiting case of a Richtmyer–Meshkov (RM) instability at a metal–vacuum interface. From this assumption, we test established theory of unstable spike and bubble growth rates, rates that link to the wavelength and amplitudes of surface perturbations. We evaluate the rate theory through novel application of modern laser Doppler velocimetry (LDV) techniques, where we coincidentally measure bubble and spike velocities from explosively shocked solid and liquid metals with a single LDV probe. We also explore the relationship of ejecta formation from a solid material to the plastic flow stress it experiences at high-strain rates () and high strains (700 %) as the fundamental link to the onset of ejecta formation. Our experimental observations allow us to approximate the strength of Cu at high strains and strain rates, revealing a unique diagnostic method for use at these extreme conditions.
Contributors
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- By Eric Adler, Anoushka Afonso, Dean B. Andropoulos, Adel Bassily-Marcus, Yaakov Beilin, Elliott Bennett-Guerrero, Howard H. Bernstein, Marc J. Bloom, David Bronheim, Albert T. Cheung, Samuel DeMaria, Deborah Dubensky, James B. Eisenkraft, Jonathan Elmer, Liza J. Enriquez, Jonathan Epstein, Jeffrey M. Feldman, Gregory W. Fischer, Brigid Flynn, Jennifer A. Frontera, Richard S. Gist, Glenn P. Gravlee, Christina L. Jeng, Ronald A. Kahn, Jenny Kam, Mukul Kapoor, Jung Kim, Roopa Kohli-Seth, Aaron F. Kopman, Tuula S. O. Kurki, Andrew B. Leibowitz, Matthew Levin, Adam I. Levine, Michael S. Lewis, Justin Lipper, Martin London, Michael L. McGarvey, Alexander J. C. Mittnacht, Timothy Mooney, Diana Mungall, Yasuharu Okuda, Peter J. Papadakos, Jayashree Raikhelkar, Lakshmi V. Ramanathan, David L. Reich, Meg A. Rosenblatt, Corey Scurlock, Tamas Seres, Linda Shore-Lesserson, Marc E. Stone, Daniel M. Thys, Judit Tolnai, David Wax, Nathaen Weitzel
- David L. Reich, Mount Sinai School of Medicine, New York
- Edited by Ronald A. Kahn, Mount Sinai School of Medicine, New York, Alexander J. C. Mittnacht, Mount Sinai School of Medicine, New York, Andrew B. Leibowitz, Mount Sinai School of Medicine, New York, Marc E. Stone, Mount Sinai School of Medicine, New York, James B. Eisenkraft, Mount Sinai School of Medicine, New York
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- Monitoring in Anesthesia and Perioperative Care
- Published online:
- 05 July 2011
- Print publication:
- 08 August 2011, pp vii-ix
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Proceedings of the Rank Forum on Vitamin D
- S. A. Lanham-New, J. L. Buttriss, L. M. Miles, M. Ashwell, J. L. Berry, B. J. Boucher, K. D. Cashman, C. Cooper, A. L. Darling, R. M. Francis, W. D. Fraser, C. P. G. M. de Groot, E. Hyppönen, M. Kiely, C. Lamberg-Allardt, H. M. Macdonald, A. R. Martineau, T. Masud, A. Mavroeidi, C. Nowson, A. Prentice, E. M. Stone, S. Reddy, R. Vieth, C. M. Williams
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- Journal:
- British Journal of Nutrition / Volume 105 / Issue 1 / 14 January 2011
- Published online by Cambridge University Press:
- 07 December 2010, pp. 144-156
- Print publication:
- 14 January 2011
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The Rank Forum on Vitamin D was held on 2nd and 3rd July 2009 at the University of Surrey, Guildford, UK. The workshop consisted of a series of scene-setting presentations to address the current issues and challenges concerning vitamin D and health, and included an open discussion focusing on the identification of the concentrations of serum 25-hydroxyvitamin D (25(OH)D) (a marker of vitamin D status) that may be regarded as optimal, and the implications this process may have in the setting of future dietary reference values for vitamin D in the UK. The Forum was in agreement with the fact that it is desirable for all of the population to have a serum 25(OH)D concentration above 25 nmol/l, but it discussed some uncertainty about the strength of evidence for the need to aim for substantially higher concentrations (25(OH)D concentrations>75 nmol/l). Any discussion of ‘optimal’ concentration of serum 25(OH)D needs to define ‘optimal’ with care since it is important to consider the normal distribution of requirements and the vitamin D needs for a wide range of outcomes. Current UK reference values concentrate on the requirements of particular subgroups of the population; this differs from the approaches used in other European countries where a wider range of age groups tend to be covered. With the re-emergence of rickets and the public health burden of low vitamin D status being already apparent, there is a need for urgent action from policy makers and risk managers. The Forum highlighted concerns regarding the failure of implementation of existing strategies in the UK for achieving current vitamin D recommendations.
Factors associated with social contacts in four communities during the 2007–2008 influenza season
- F. DeSTEFANO, M. HABER, D. CURRIVAN, T. FARRIS, B. BURRUS, B. STONE-WIGGINS, A. McCALLA, H. GULED, H. SHIH, P. EDELSON, S. WETTERHALL
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- Journal:
- Epidemiology & Infection / Volume 139 / Issue 8 / August 2011
- Published online by Cambridge University Press:
- 14 October 2010, pp. 1181-1190
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Mathematical models of influenza pandemics are sensitive to changes in contact rates between individuals. We conducted population-based telephone surveys in four North Carolina counties to determine the number of social interactions between individuals during the 2007–2008 influenza season. Influenza activity was monitored through sentinel medical practices. Among 3845 adults, the number of social contacts varied with age, was lower on weekends than on weekdays, and further decreased during school holiday periods. Adults with influenza-like illnesses had fewer social contacts. Adults' contacts in the community setting increased during periods of peak influenza activity. Among 290 children, potential contacts (i.e. other people in the same location) were lowest among preschool-age children and decreased on weekends and during school holidays. In adjusted analyses, children's potential social contacts did not change during periods of peak influenza activity. These results should be useful for modelling influenza epidemics and pandemics and in planning mitigation and response strategies.
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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. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. 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. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. 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. Nicholson, George W. E. Nickelsburg, Tatyana Nikolskaya, Damayanthi M. A. Niles, Bertil Nilsson, Nyambura Njoroge, Fidelis Nkomazana, Mary Beth Norton, Christian Nottmeier, Sonene Nyawo, Anthère Nzabatsinda, Edward T. Oakes, Gerald O'Collins, Daniel O'Connell, David W. Odell-Scott, Mercy Amba Oduyoye, Kathleen O'Grady, Oyeronke Olajubu, Thomas O'Loughlin, Dennis T. Olson, J. Steven O'Malley, Cephas N. Omenyo, Muriel Orevillo-Montenegro, César Augusto Ornellas Ramos, Agbonkhianmeghe E. Orobator, Kenan B. Osborne, Carolyn Osiek, Javier Otaola Montagne, Douglas F. Ottati, Anna May Say Pa, Irina Paert, Jerry G. Pankhurst, Aristotle Papanikolaou, Samuele F. Pardini, Stefano Parenti, Peter Paris, Sung Bae Park, Cristián G. Parker, Raquel Pastor, Joseph Pathrapankal, Daniel Patte, W. Brown Patterson, Clive Pearson, Keith F. Pecklers, Nancy Cardoso Pereira, David Horace Perkins, Pheme Perkins, Edward N. Peters, Rebecca Todd Peters, Bishop Yeznik Petrossian, Raymond Pfister, Peter C. Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. Rubenstein, Rosemary Radford Ruether, Markku Ruotsila, John E. Rybolt, Risto Saarinen, John Saillant, Juan Sanchez, Wagner Lopes Sanchez, Hugo N. Santos, Gerhard Sauter, Gloria L. Schaab, Sandra M. Schneiders, Quentin J. Schultze, Fernando F. Segovia, Turid Karlsen Seim, Carsten Selch Jensen, Alan P. F. Sell, Frank C. Senn, Kent Davis Sensenig, Damían Setton, Bal Krishna Sharma, Carolyn J. Sharp, Thomas Sheehan, N. Gerald Shenk, Christian Sheppard, Charles Sherlock, Tabona Shoko, Walter B. Shurden, Marguerite Shuster, B. Mark Sietsema, Batara Sihombing, Neil Silberman, Clodomiro Siller, Samuel Silva-Gotay, Heikki Silvet, John K. Simmons, Hagith Sivan, James C. Skedros, Abraham Smith, Ashley A. Smith, Ted A. Smith, Daud Soesilo, Pia Søltoft, Choan-Seng (C. S.) Song, Kathryn Spink, Bryan Spinks, Eric O. Springsted, Nicolas Standaert, Brian Stanley, Glen H. Stassen, Karel Steenbrink, Stephen J. Stein, Andrea Sterk, Gregory E. Sterling, Columba Stewart, Jacques Stewart, Robert B. Stewart, Cynthia Stokes Brown, Ken Stone, Anne Stott, Elizabeth Stuart, Monya Stubbs, Marjorie Hewitt Suchocki, David Kwang-sun Suh, Scott W. Sunquist, Keith Suter, Douglas Sweeney, Charles H. Talbert, Shawqi N. Talia, Elsa Tamez, Joseph B. Tamney, Jonathan Y. Tan, Yak-Hwee Tan, Kathryn Tanner, Feiya Tao, Elizabeth S. Tapia, Aquiline Tarimo, Claire Taylor, Mark Lewis Taylor, Bishop Abba Samuel Wolde Tekestebirhan, Eugene TeSelle, M. Thomas Thangaraj, David R. Thomas, Andrew Thornley, Scott Thumma, Marcelo Timotheo da Costa, George E. “Tink” Tinker, Ola Tjørhom, Karen Jo Torjesen, Iain R. Torrance, Fernando Torres-Londoño, Archbishop Demetrios [Trakatellis], Marit Trelstad, Christine Trevett, Phyllis Trible, Johannes Tromp, Paul Turner, Robert G. Tuttle, Archbishop Desmond Tutu, Peter Tyler, Anders Tyrberg, Justin Ukpong, Javier Ulloa, Camillus Umoh, Kristi Upson-Saia, Martina Urban, Monica Uribe, Elochukwu Eugene Uzukwu, Richard Vaggione, Gabriel Vahanian, Paul Valliere, T. J. 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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- The Cambridge Dictionary of Christianity
- Published online:
- 05 August 2012
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- 20 September 2010, pp xi-xliv
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Chemical control of an organophosphorus-and carbamate-resistant strain of Boophilus microplus (Can.) from Queensland
- W. J. Roulston, B. F. Stone, J. T. Wilson, L. I. White
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- Journal:
- Bulletin of Entomological Research / Volume 58 / Issue 2 / November 1968
- Published online by Cambridge University Press:
- 10 July 2009, pp. 379-392
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Recognition in 1963 in central Queensland of the Ridgelands strain of Boophilus microplus (Can.), resistant in varying degrees in laboratory tests to all acaricides commercially available in Queensland, Australia, led to spraying trials on cattle with these acaricides to assess their effect on the resistant strain. Dosage mortality tests on larvae exposed in acaricide-impregnated filter papers, indicated the following levels of resistance, carbary 13×, carbophenothion 17×, coumaphos 1.6×, diazinon 19×, dioxathion 7.2× and ethion 2.7×.
Stalled cattle infested with either susceptible Yeerongpilly or resistant Ridgelands ticks were sprayed with the recommended concentration of commercially formulated acaricide. Efficiency of treatment was determined by comparing the number of ticks falling from sprayed and unsprayed cattle. Coumaphos (0.025%) and ethion (0.075%) produced efficient control of the resistant strain, but carbophenothion (0.086%), diazinon (0.05%) and dioxathion (0.075%) allowed considerable numbers of the resistant strain of ticks to survive. Carbaryl (0.3%) as a melt-type formulation gave inconsistent results and possible reasons are discussed. Poor control of the resistant strain was largely due to failure to kill the nymph stage.
There was general correspondence between the resisdence level determined in laboratory tests and the degree of control achieved in spraying trials. However, the reletively small difference between resistence levels of 2–3× (coumaphos and ethion) and 7× (dioxathion) was critical in the practical control of resistant ticks on cattle.
The following chemicals gave excellent control of the Ridgelands strain in spraying trials on stalled cattle: bromophos (0.15%), bromophos ethyl (0.1%), chlorfenvinphos (0.06%), chlorxylam (0.5%), Ciodrin (0.1%) Dursban (0.025%), fenchlorphos (0.2%), GS13002 (0.05%), Imidan (0.075%), methidathion (0.05%) and SD8448 (0.025%). Malathion (0.5%), prothidathion (0.075%), macarbam (0.075%) and RD12308 (0.2%) controlled the Yeerongpilly but not the Ridgelands strain. Arsenic (0.2%) produced about equal mortality in both strains, but was clearly a less efficient acaricide than organophosphorus chemicals.
II.—Notes on the Diamond-bearing Rock of Kimberley, South Africa
- J. B. Stone, T. G. Bonney, C. A. Raisin
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- Journal:
- Geological Magazine / Volume 2 / Issue 11 / November 1895
- Published online by Cambridge University Press:
- 01 May 2009, pp. 492-502
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It may be fairly asserted that increased geological interest attaches to the deeper workings of the Kimberley Diamond Mines as they proceed. The remarkable development of underground mining, following upon the amalgamation of interests, which was the outcome of the collapse of the surface workings in 1886, or thereabout, has offered better opportunities for observation, not only of the diamond matrix-material but also of the varying characteristics of the neighbouring rock formations.
Quantitative genetics of larval life-history traits in Rana temporaria in different environmental conditions
- ANE T. LAUGEN, LOESKE E. B. KRUUK, ANSSI LAURILA, KATJA RÄSÄNEN, JONATHAN STONE, JUHA MERILÄ
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- Journal:
- Genetical Research / Volume 86 / Issue 3 / December 2005
- Published online by Cambridge University Press:
- 25 November 2005, pp. 161-170
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The degree to which genetic variation in a given trait varies among different populations of the same species and across different environments has seldom been quantified in wild vertebrate species. We investigated the expression of genetic variability and maternal effects in three larval life-history traits of the amphibian Rana temporaria. In a factorial laboratory experiment, five widely separated populations (max. 1600 km) were subjected to two different environmental treatments. Animal model analyses revealed that all traits were heritable (h2≈0·20) in all populations and under most treatment combinations. Although the cross-food treatment genetic correlations were close to unity, heritabilities under a restricted food regime tended to be lower than those under an ad libitum food regime. Likewise, maternal effects (m2≈0·05) were detected in most traits, and they tended to be most pronounced under restricted food conditions. We detected several cross-temperature genetic and maternal effects correlations that were lower than unity, suggesting that genotype–environment interactions and maternal effect–environment interactions are a significant source of phenotypic variation. The results reinforce the perspective that although the expression of genetic and maternal effects may be relatively homogeneous across different populations of the same species, local variation in environmental conditions can lead to significant variation in phenotypic expression of quantitative traits through genotype–environment and maternal effect–environment interactions.
Differences in the neurochemical characteristics of the cortex and striatum of mice with cerebral malaria
- C. J. CLARK, R. S. PHILLIPS, R. B. McMILLAN, I. O. MONTGOMERY, T. W. STONE
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- Journal:
- Parasitology / Volume 130 / Issue 1 / January 2005
- Published online by Cambridge University Press:
- 13 December 2004, pp. 23-29
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Fatal murine cerebral malaria is an encephalitis and not simply a local manifestation in the brain of a systemic process. Histopathologically, murine cerebral malaria has been characterized by monocyte adherence to the endothelium of the microvasculature, activation of microglial cells, swelling of endothelial cell nuclei, microvasculature damage, and breakdown of the blood-brain barrier with cerebral oedema. Brain parenchymal cells have been proposed to be actively involved in the pathogenesis of murine cerebral malaria. We, therefore, compared the neurochemical characteristics of Plasmodium berghei ANKA-infected mice with controls to determine whether cerebral malarial infection significantly impairs specific neuronal populations. Between 6 and 7 days after infection, we found a significant loss of neurones containing substance P, with preservation of cells containing somatostatin, neuropeptide Y and calbindin in the striatum of infected mice compared with controls. In the cortex of infected mice, we found a significant reduction in the number of cells containing substance P, somatostatin and neuropeptide Y. The number of calbindin-containing neurones was unchanged. This study found significant changes in the neurochemical characteristics of the cortex and striatum of mice infected with P. berghei ANKA, which may contribute to their cerebral symptoms.
4 - Drops and bubbles
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- By S. Chandra, C. T. Avedisian, M. P. Brenner, X. D. Shi, J. Eggers, S. R. Nagel, M. Tjahjadi, J. M. Ottino, PH. Marmottant, E. Villermaux, B. Vukasinovic, A. Glezer, M. K. Smith, A. Lozano, C. J. Call, C. Dopazo, D. E. Nikitopoulos, A. J. Kelly, D. Frost, B. Sturtevant, M. M. Weislogel, S. Lichter, M. Manga, H. A. Stone, J. Buchholz, L. Sigurdson, B. Peck
- M. Samimy, Ohio State University, K. S. Breuer, Brown University, Rhode Island, L. G. Leal, University of California, Santa Barbara, P. H. Steen, Cornell University, New York
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- A Gallery of Fluid Motion
- Published online:
- 25 January 2010
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- 12 January 2004, pp 42-53
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Summary
The collision of a droplet with a solid surface
The photographs displayed above show the impact, spreading, and boiling history of n-heptane droplets on a stainless steel surface. The impact velocity, Weber number, and initial droplet diameter are constant (values of 1 m/s, 43 and 1.5 mm respectively), and the view is looking down on the surface at an angle of about 30°. The photographs were taken using a spark flash method and the flash duration was 0.5 μs. The dynamic behavior illustrated in the photographs is a consequence of varying the initial surface temperature.
The effect of surface temperature on droplet shape may be seen by reading across any row; the evolution of droplet shape at various temperatures may be seen by reading down any column. An entrapped air bubble can be seen in the drop when the surface temperature is 24°C. At higher temperatures vigorous bubbling, rather like that of a droplet sizzling on a frying pan, is seen (the boiling point of n-heptane is 98°C) but the bubbles disappear as the Leidenfrost temperature of n-heptane (about 200°C) is exceeded because the droplet become levitated above a cushion of its own vapor and does not make direct contact with the surface. The droplet shape is unaffected by surface temperature in the early stage of the impact process (t≤0.8 ms) but is affected by temperature at later time (cf. t≥ 1.6 ms) because of the progressive influence of intermittent solid-liquid contact as temperature is increased.
Americium-Curium Vitrification Process Development (U)
- A. P. Fellinger, M. A. Baich, B. J. Hardy, G. T. Jannik, T. M. Jones, J. E. Marra, C. B. Miller, D. H. Miller, D. K. Peeler, T. K. Snyder, M. E. Stone, D. C. Witt
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- Journal:
- MRS Online Proceedings Library Archive / Volume 556 / 1999
- Published online by Cambridge University Press:
- 10 February 2011, 367
- Print publication:
- 1999
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The successful demonstration of sequentially drying, calcining and vitrifying an oxalate slurry in the Drain Tube Test Stand (DTTS) vessel provided the process basis for testing on a larger scale in a cylindrical induction heated melter. A single processing issue, that of batch volume expansion, was encountered during the initial stages of testing. The increase in batch volume centered on a sintered frit cap and high temperature bubble formation. The formation of a sintered frit cap expansion was eliminated with the use of cullet. Volume expansions due to high temperature bubble formation (oxygen liberation from cerium reduction) were mitigated in the DTTS melter vessel through a vessel temperature profile that effectively separated the softening point of the glass cullet and the evolving oxygen from cerium reduction. An increased processing temperature of 1470°C and a two hour hold time to fine any remaining bubbles successfully reduced bubbles in the poured glass to an acceptable level. The success of the preliminary process demonstrations provided a workable process basis that was directly applicable to the newly installed Cylindrical Induction Melter (CIM) system, making the batch flowsheet the preferred option for vitrification of the americium-curium surrogate feed stream.
The Astronomical Low-Frequency Array (ALFA)
- D. L. Jones, K. W. Weiler, R. J. Allen, M. M. Desch, W. C. Erickson, M. L. Kaiser, N. E. Kassim, T. B. H. Kuiper, M. J. Mahoney, K. A. Marsh, R. A. Perley, R. A. Preston, R. G. Stone
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- Journal:
- International Astronomical Union Colloquium / Volume 164 / 1998
- Published online by Cambridge University Press:
- 12 April 2016, pp. 393-394
- Print publication:
- 1998
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The ALFA mission is designed to map the entire sky at frequencies between approximately 0.3 and 30 MHz with angular resolution limited by interstellar and interplanetary scattering. Most of this region of the spectrum is inaccessible from the ground because of absorption and refraction by the Earth’s ionosphere. A wide range of astrophysical questions concerning solar system, galactic, and extragalactic objects could be answered with high resolution images at low frequencies, where absorption effects and coherent emission processes become important and the synchrotron lifetimes of electrons are comparable to the age of the universe.
Er3+-Doped Silica and Hybrid Organic/Inorganic Silica Gels
- B. T. Stone, K. L. Bray
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- Journal:
- MRS Online Proceedings Library Archive / Volume 435 / 1996
- Published online by Cambridge University Press:
- 15 February 2011, 617
- Print publication:
- 1996
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The fluorescence properties of Er3+ in densified sol-gel silica and alkyl-modified silicates are presented. In sol-gel silica, strong infrared (4I13/2→4I15/2) emission was observed over a wide range of Er3+ concentrations. The effect of metal ion co-dopants, which are known to inhibit clustering of Eu3+ in sol-gel silica, on Er3+ fluorescence are also considered. The co-dopants La3+, Y3+, Yb3+, and Al3+ are increasingly more effective at inhibiting Er3+ clustering and promoting a more uniform spatial distribution of Er3+ ions. Lifetime studies were also conducted to assess the extent of hydroxyl quenching.
Organic/inorganic hybrid silica gels are expected to contain a lower amount of water than simple sol-gel silica gels and should be better hosts for rare earth ions. Er3+-doped hybrid organic/inorganic gels were prepared using Si(OC2H5)4 and CH3Si(OC2H5)3, (CH3)2Si(OC2H5)2 or C2H5Si(OC 2H5)3. Er3+ fluorescence spectra and lifetime studies of these gels are presented and compared to simple Er3+-doped sol-gel silica. The effect of organic modification on Er3+ clustering and hydroxyl retention are discussed. Er3+ upconversion properties are also discussed.