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Seroprevalence of Toxoplasma gondii and associated risk factors for infection in the Netherlands: third cross-sectional national study
- Oda E. van den Berg, Kamelia R. Stanoeva, Rens Zonneveld, Denise Hoek-van Deursen, Fiona R. van der Klis, Jan van de Kassteele, Eelco Franz, Marieke Opsteegh, Ingrid H. M. Friesema, Laetitia M. Kortbeek
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- Journal:
- Epidemiology & Infection / Volume 151 / 2023
- Published online by Cambridge University Press:
- 28 July 2023, e136
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A third nationally representative serosurvey was performed to study the changes in Toxoplasma gondii (T. gondii) seroprevalence in the Netherlands over a 20-year time span and to identify and confirm risk factors for acquired toxoplasmosis. This cross-sectional study (conducted in 2016/2017) was designed similarly to the previous two studies (1995/1996 and 2006/2007) and included a questionnaire and serum sampling among Dutch residents. Factors associated with seropositivity for T. gondii were determined using multivariable analysis of the questionnaire-derived data. The earlier observed decrease in T. gondii seroprevalence between 1995/1996 and 2006/2007 (from 40.5% to 26.0%) did not continue into 2016/2017 (29.9%). Similarly to the previous studies, the seroprevalence increased with age and varied among regions. In all studies, higher T. gondii seropositivity was associated with increasing age, lower educational level, not living in the Southeast, and eating raw or semi-cooked pork. The incidence of congenital toxoplasmosis was estimated at 1.3/1000 (95% CI 0.9–1.8) live-born children in 2017. As the seroprevalence of T. gondii in the Netherlands did not decrease over the last decade, an increase in public health awareness is needed and prevention measures may need to be taken to achieve a further reduction in T. gondii infections in the Netherlands.
Validation of the FRESH Austin food frequency questionnaire using multiple 24-h dietary recalls
- Christine ES Jovanovic, Jacob Whitefield, Deanna M Hoelscher, Boajiang Chen, Nalini Ranjit, Alexandra E van den Berg
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- Journal:
- Public Health Nutrition / Volume 25 / Issue 6 / June 2022
- Published online by Cambridge University Press:
- 26 May 2021, pp. 1586-1594
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Objective:
The purpose of the current study was to examine the validity of an FFQ utilised in the Food Retail: Evaluating Strategies for a Healthy Austin (FRESH Austin) study, designed to evaluate changes in the consumption of fruits and vegetables (FV) in diverse low-income communities in Austin, TX.
Design:The FRESH Austin FFQ was validated against three 24-h dietary recalls (24hDR). All dietary assessments were administered (in-person or by telephone) by trained investigators.
Setting:Recruitment was conducted at sites within the geographic areas targeted in the FRESH Austin recruitment. People at a community health clinic, a local health centre and a YMCA within the intervention area were approached by trained and certified data collectors, and invited to participate.
Participants:Among fifty-six participants, 83 % were female, 46 % were non-White, 24 % had income < $25 K/year and 30 % spoke only/mostly Spanish at home.
Results:The FFQ and average of three 24hDR produce similar estimates of average total servings/d across FV (6·68 and 6·40 servings/d, respectively). Correlations produced measures from 0·01 for ‘Potatoes’ and 0·59 for ‘Other Vegetables’. Mean absolute percentage errors values were small for all FV, suggesting the variance of the error estimates was also small. Bland–Altman plots indicate acceptable levels of agreement between the two methods.
Conclusion:These outcomes indicate that the FRESH FFQ is a valid instrument for assessing FV consumption. The validation of the FRESH Austin FFQ provides important insights for evaluating community-based efforts to increase FV consumption in diverse populations.
303 - Residential aged care staff’s perception of and response to behavioral and psychological symptoms of dementia – a qualitative analysis of clinical care notes
- Willem S. Eikelboom, Jana Koch, Elizabeth Beattie, Nicola Lautenschlager, Colleen Doyle, Kaarin J. Anstey, Esther van den Berg, Janne M. Papma, Moyra E. Mortby
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- Journal:
- International Psychogeriatrics / Volume 32 / Issue S1 / October 2020
- Published online by Cambridge University Press:
- 04 November 2020, p. 61
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Background:
Behavioral and psychological symptoms of dementia (BPSD) are very prevalent among individuals with dementia living in residential aged care. The development and implementation of new non-pharmacological interventions to reduce BPSD requires knowledge on the current perception and clinical practice of the care staff. We analyzed clinical care notes to examine the way residential aged care staff reported and managed BPSD in their daily clinical practice.
Methods:We examined semi-structured care notes relating to the presentation and management of behaviors of 76 older residents (67% female; aged 67-101; 75% with formal dementia diagnosis) prior to participating in the Australian BPSDPLUS Program. As part of standard clinical practice in three residential aged care facilities, staff document the presentation and management of behaviors amongst residents. Using an inductive thematic analytical approach, we analyzed the reported data in the one and a half months prior to commencing participation in the BPSDPLUS Program. Care notes were coded and analyzed by two independent assessors and they discussed themes until consensus was reached.
Results:A total of 465 behavior charts were completed in the one and a half months prior to the commencement of the BPSDPLUS Program. The number of behavioral charts varied widely across residents (Mean=7.3, range 0–93). Behaviors such as refusal of care, repetitive verbal behaviors, and wandering were most often mentioned, while apathy and affective and psychotic symptoms were seldomly reported. When confronted with BPSD, the clinical care notes indicated that care staff tend to respond in a reactive manner by reassuring, redirecting, or distracting the resident. Furthermore, it seems that staff did not routinely investigate potential underlying causes of the BPSD.
Conclusions:These results suggest that the residential care staff primarily detected and responded to externalizing behaviors, while more internalizing behaviors were not reported. Potential underrecognition of internalizing behaviors, as well as the fact that the staff did not routinely examine causes of BPSD are vital observations for the development and implementation of nonpharmacological interventions and care programs targeting BPSD in residential aged care.
Emotion Recognition and Traffic-Related Risk-Taking Behavior in Patients with Neurodegenerative Diseases
- Nils S. van den Berg, Fransje E. Reesink, Edward H.F. de Haan, Hubertus P.H. Kremer, Jacoba M. Spikman, Rients B. Huitema
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- Journal:
- Journal of the International Neuropsychological Society / Volume 27 / Issue 2 / February 2021
- Published online by Cambridge University Press:
- 19 August 2020, pp. 136-145
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Objectives:
Neurodegenerative diseases (NDDs), such as Alzheimer’s disease, frontotemporal dementia, dementia with Lewy bodies, and Huntington’s disease, inevitably lead to impairments in higher-order cognitive functions, including the perception of emotional cues and decision-making behavior. Such impairments are likely to cause risky daily life behavior, for instance, in traffic. Impaired recognition of emotional expressions, such as fear, is considered a marker of impaired experience of emotions. Lower fear experience can, in turn, be related to risk-taking behavior. The aim of our study was to investigate whether impaired emotion recognition in patients with NDD is indeed related to unsafe decision-making in risky everyday life situations, which has not been investigated yet.
Methods:Fifty-one patients with an NDD were included. Emotion recognition was measured with the Facial Expressions of Emotions: Stimuli and Test (FEEST). Risk-taking behavior was measured with driving simulator scenarios and the Action Selection Test (AST). Data from matched healthy controls were used: FEEST (n = 182), AST (n = 36), and driving simulator (n = 18).
Results:Compared to healthy controls, patients showed significantly worse emotion recognition, particularly of anger, disgust, fear, and sadness. Furthermore, patients took significantly more risks in the driving simulator rides and the AST. Only poor recognition of fear was related to a higher amount of risky decisions in situations involving a direct danger.
Conclusions:To determine whether patients with an NDD are still fit to drive, it is crucial to assess their ability to make safe decisions. Measuring emotion recognition may be a valuable contribution to this judgment.
Improved representation of East Antarctic surface mass balance in a regional atmospheric climate model
- J.M. Van Wessem, C.H. Reijmer, M. Morlighem, J. Mouginot, E. Rignot, B. Medley, I. Joughin, B. Wouters, M.A. Depoorter, J.L. Bamber, J.T.M. Lenaerts, W.J. Van De Berg, M.R. Van Den Broeke, E. Van Meijgaard
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- Journal:
- Journal of Glaciology / Volume 60 / Issue 222 / 2014
- Published online by Cambridge University Press:
- 10 July 2017, pp. 761-770
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This study evaluates the impact of a recent upgrade in the physics package of the regional atmospheric climate model RACMO2 on the simulated surface mass balance (SMB) of the Antarctic ice sheet. The modelled SMB increases, in particular over the grounded ice sheet of East Antarctica (+44 Gt a–1), with a small change in West Antarctica. This mainly results from an increase in precipitation, which is explained by changes in the cloud microphysics, including a new parameterization for ice cloud supersaturation, and changes in large-scale circulation patterns, which alter topographically forced precipitation. The spatial changes in SMB are evaluated using 3234 in situ SMB observations and ice-balance velocities, and the temporal variability using GRACE satellite retrievals. The in situ observations and balance velocities show a clear improvement of the spatial representation of the SMB in the interior of East Antarctica, which has become considerably wetter. No improvements are seen for West Antarctica and the coastal regions. A comparison of model SMB temporal variability with GRACE satellite retrievals shows no significant change in performance.
Sodium pyrophosphate enhances iron bioavailability from bouillon cubes fortified with ferric pyrophosphate
- Colin I. Cercamondi, Guus S. M. J. E. Duchateau, Rajwinder K. Harika, Robin van den Berg, Peter Murray, Wieneke P. Koppenol, Christophe Zeder, Michael B. Zimmermann, Diego Moretti
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- Journal:
- British Journal of Nutrition / Volume 116 / Issue 3 / 14 August 2016
- Published online by Cambridge University Press:
- 08 June 2016, pp. 496-503
- Print publication:
- 14 August 2016
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Fe fortification of centrally manufactured and frequently consumed condiments such as bouillon cubes could help prevent Fe deficiency in developing countries. However, Fe compounds that do not cause sensory changes in the fortified product, such as ferric pyrophosphate (FePP), exhibit low absorption in humans. Tetra sodium pyrophosphate (NaPP) can form soluble complexes with Fe, which could increase Fe bioavailability. Therefore, the aim of this study was to investigate Fe bioavailability from bouillon cubes fortified with either FePP only, FePP+NaPP, ferrous sulphate (FeSO4) only, or FeSO4+NaPP. We first conducted in vitro studies using a protocol of simulated digestion to assess the dialysable and ionic Fe, and the cellular ferritin response in a Caco-2 cell model. Second, Fe absorption from bouillon prepared from intrinsically labelled cubes (2·5 mg stable Fe isotopes/cube) was assessed in twenty-four Fe-deficient women, by measuring Fe incorporation into erythrocytes 2 weeks after consumption. Fe bioavailability in humans increased by 46 % (P<0·005) when comparing bouillons fortified with FePP only (4·4 %) and bouillons fortified with FePP+NaPP (6·4 %). Fe absorption from bouillons fortified with FeSO4 only and with FeSO4+NaPP was 33·8 and 27·8 %, respectively (NS). The outcome from the human study is in agreement with the dialysable Fe from the in vitro experiments. Our findings suggest that the addition of NaPP could be a promising strategy to increase Fe absorption from FePP-fortified bouillon cubes, and if confirmed by further research, for other fortified foods with complex food matrices as well.
Antidepressants and heart-rate variability in older adults: a population-based study
- R. Noordam, M. E. van den Berg, M. N. Niemeijer, N. Aarts, A. Hofman, H. Tiemeier, J. A. Kors, B. H. Stricker, M. Eijgelsheim, L. E. Visser, P. R. Rijnbeek
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- Journal:
- Psychological Medicine / Volume 46 / Issue 6 / April 2016
- Published online by Cambridge University Press:
- 18 December 2015, pp. 1239-1247
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Background
Tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs) may be associated with lower heart rate variability (HRV), a condition associated with increased mortality risk. We aimed to investigate the association between TCAs, SSRIs and HRV in a population-based study.
MethodIn the prospective Rotterdam Study cohort, up to five electrocardiograms (ECGs) per participant were recorded (1991–2012). Two HRV variables were studied based on 10-s ECG recordings: standard deviation of normal-to-normal RR intervals (SDNN) and root mean square of successive RR interval differences (RMSSD). We compared the HRV on ECGs recorded during use of antidepressants with the HRV on ECGs recorded during non-use of any antidepressant. Additionally, we analysed the change in HRV on consecutive ECGs. Those who started or stopped using antidepressants before the second ECG were compared with non-users on two ECGs.
ResultsWe included 23 647 ECGs from 11 729 participants (59% women, mean age 64.6 years at baseline). Compared to ECGs recorded during non-use of antidepressants (n = 22 971), SDNN and RMSSD were lower in ECGs recorded during use of TCAs (n = 296) and SSRIs (n = 380). Participants who started using TCAs before the second ECG had a decrease in HRV and those who stopped had an increase in HRV compared to consistent non-users (p < 0.001). Starting or stopping SSRIs was not associated with HRV changes.
ConclusionTCAs were associated with a lower HRV in all analyses, indicating a real drug effect. For SSRIs the results are mixed, indicating a weaker association, possibly due to other factors.
Cannabis use and transition to psychosis in individuals at ultra-high risk: review and meta-analysis
- T. Kraan, E. Velthorst, L. Koenders, K. Zwaart, H. K. Ising, D. van den Berg, L. de Haan, M. van der Gaag
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- Psychological Medicine / Volume 46 / Issue 4 / March 2016
- Published online by Cambridge University Press:
- 16 November 2015, pp. 673-681
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Background
Previous research has established the relationship between cannabis use and psychotic disorders. Whether cannabis use is related to transition to psychosis in patients at ultra-high risk (UHR) for psychosis remains unclear. The present study aimed to review the existing evidence on the association between cannabis use and transition to psychosis in UHR samples.
MethodA search of PsychInfo, Embase and Medline was conducted from 1996 to August 2015. The search yielded 5559 potentially relevant articles that were selected on title and abstract. Subsequently 36 articles were screened on full text for eligibility. Two random-effects meta-analyses were performed. First, we compared transition rates to psychosis of UHR individuals with lifetime cannabis use with non-cannabis-using UHR individuals. Second, we compared transition rates of UHR individuals with a current DSM-IV cannabis abuse or dependence diagnosis with lifetime users and non-using UHR individuals.
ResultsWe found seven prospective studies reporting on lifetime cannabis use in UHR subjects (n = 1171). Of these studies, five also examined current cannabis abuse or dependence. Lifetime cannabis use was not significantly associated with transition to psychosis [odds ratio (OR) 1.14, 95% confidence interval (CI) 0.856–1.524, p = 0.37]. A second meta-analysis yielded an OR of 1.75 (95% CI 1.135–2.710, p = 0.01), indicating a significant association between current cannabis abuse or dependence and transition to psychosis.
ConclusionsOur results show that cannabis use was only predictive of transition to psychosis in those who met criteria for cannabis abuse or dependence, tentatively suggesting a dose–response relationship between current cannabis use and transition to psychosis.
Effects of Twin Separation in Primary School
- Marieke van Leeuwen, Stéphanie M. van den Berg, Toos C. E. M. van Beijsterveldt, Dorret I. Boomsma
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- Twin Research and Human Genetics / Volume 8 / Issue 4 / 01 August 2005
- Published online by Cambridge University Press:
- 21 February 2012, pp. 384-391
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We studied the short- and long-term effects of classroom separation in twins on behavior problems and academic performance. Short-term effects were studied at age 7 in twins separated at age 5 and long-term effects at age 12 in twins who had been separated or together most of the time at school. Behavior problems were rated by mothers (Child Behavior Checklist at ages 3, 7 and 12) and teachers (Teacher Report Form at ages 7 and 12). Academic achievement was measured at age 12 using a national academic achievement test (CITO). At age 7, twins from separated pairs had more internalizing and externalizing problems than non- separated twins, as rated by both mothers and teachers. Only for the maternal ratings of internalizing problems, however, could these effects be attributed to the separation itself and not to preexisting problems (at age 3) between separated and nonseparated twins. Long-term effects of separation were significant for maternal and teacher ratings of internalizing and externalizing problems, but these effects could be explained by preexisting differences between separated and nonseparated groups. There were no differences in academic achievement between the separated and nonsepa- rated group. These results suggest that the decision to separate twins when they go to school is based in part on the existing behavioral problems of the twins and that, in the long run, separation does not affect problem behavior or academic achievement. The findings were the same for monozygotic and dizygotic twins.
Netherlands Twin Register: A Focus on Longitudinal Research
- Dorret I. Boomsma, Jacqueline M. Vink, Toos C. E .M. van Beijsterveldt, Eco J. C. de Geus, A. Leo Beem, Elles J. C. M. Mulder, Eske M. Derks, Harriette Riese, Gonneke A. H. M. Willemsen, Meike Bartels, Mireille van den Berg, Nina H. M. Kupper, Tinca J. C. Polderman, Danielle Posthuma, Marjolein J. H. Rietveld, Janine H. Stubbe, Louise I. Knol, Therese Stroet, G. Caroline M. van Baal
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- Twin Research / Volume 5 / Issue 5 / 01 October 2002
- Published online by Cambridge University Press:
- 21 February 2012, pp. 401-406
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In 1986 we began The Netherlands Twin Register (NTR) by recruiting young twins and multiples a few weeks or months after birth. Currently we register around 50% of all newborn multiples in The Netherlands. Their parents receive a questionnaire at registration and afterwards when the children are 2, 3, 5, 7, 10 and 12 years of age. Teachers are asked to rate the behavior of the children at ages 7, 10 and 12 years. Adolescent and young-adult twins were recruited through City Councils in the early 1990s. These twins, their parents and siblings participate in longitudinal survey studies that include items about health, fertility, lifestyle, addiction, personality and psychopathology, religion, socioeconomic status, and educational attainment. The total number of twins and multiples registered with the NTR is currently over 60,000. Subgroups of twins and siblings take part in studies of cognitive development, brain function and neuropsychological indices of attention processes, and molecular genetic studies of classical and behavioral cardiovascular risk factors. DNA samples are currently collected in selected twin families for two large linkage studies, which aim to find QTLs for anxious depression and for nicotine addiction. Sisters who are mothers of DZ twins contribute DNA samples for a linkage study of DZ twinning. Large cohorts of phenotyped family members from the general population are very valuable for genetic epidemiological studies and permit selection of informative families for gene finding studies.
Polymorphisms in the FGF2 Gene and Risk of Serous Ovarian Cancer: Results From the Ovarian Cancer Association Consortium
- Sharon E. Johnatty, Jonathan Beesley, Xiaoqing Chen, Amanda B. Spurdle, Anna DeFazio, Penelope M. Webb, Australian Ovarian Cancer Study Group, Australian Cancer Study (Ovarian Cancer), Ellen L. Goode, David N. Rider, Robert A. Vierkant, Stephanie Anderson, Anna H. Wu, Malcolm Pike, David Van Den Berg, Kirsten Moysich, Roberta Ness, Jennifer Doherty, Mary-Anne Rossing, Celeste Leigh Pearce, Georgia Chenevix-Trench
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- Twin Research and Human Genetics / Volume 12 / Issue 3 / 01 June 2009
- Published online by Cambridge University Press:
- 21 February 2012, pp. 269-275
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Fibroblast growth factor (FGF)-2 (basic) is a potent angiogenic molecule involved in tumor progression, and is one of several growth factors with a central role in ovarian carcinogenesis. We hypothesized that common single nucleotide polymorphisms (SNPs) in the FGF2 gene may alter angiogenic potential and thereby susceptibility to ovarian cancer. We analyzed 25 FGF2 tgSNPs using five independent study populations from the United States and Australia. Analysis was restricted to non-Hispanic White women with serous ovarian carcinoma (1269 cases and 2829 controls). There were no statistically significant associations between any FGF2 SNPs and ovarian cancer risk. There were two nominally statistically significant associations between heterozygosity for two FGF2 SNPs (rs308379 and rs308447; p < .05) and serous ovarian cancer risk in the combined dataset, but rare homozygous estimates did not achieve statistical significance, nor were they consistent with the log additive model of inheritance. Overall genetic variation in FGF2 does not appear to play a role in susceptibility to ovarian cancer.
Contributors
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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
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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The Brixton Spatial Anticipation Test as a test for executive function: Validity in patient groups and norms for older adults
- ESTHER VAN DEN BERG, GUDRUN M. S. NYS, AUGUSTINA M. A. BRANDS, CARLA RUIS, MARTINE J. E. VAN ZANDVOORT, ROY P. C. KESSELS
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- Journal:
- Journal of the International Neuropsychological Society / Volume 15 / Issue 5 / September 2009
- Published online by Cambridge University Press:
- 01 September 2009, pp. 695-703
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Impairments in executive functioning frequently occur after acquired brain damage, in psychiatric disorders, and in relation to aging. The Brixton Spatial Anticipation Test is a relatively new measure for assessing the ability to detect and follow a rule, an important aspect of executive functioning. To date, normative data on this task are limited, particularly concerning the elderly. This study presents age- and education-adjusted regression-based norms obtained in a group of healthy older participants (n = 283; mean age 67.4 ± 8.5 years). The applicability and validity of these norms were further examined in different groups of patients with stroke (n = 106), diabetes mellitus (n = 376), MCI/early dementia (n = 70), psychiatric disorders (n = 63), and Korsakoff’s syndrome (n = 41). The results showed that patients with Korsakoff’s syndrome, stroke, and psychiatric disorders performed significantly worse than healthy controls. Test-retest correlation (n = 83), learning effects, and correlations with other neuropsychological tests were also explored. Based on the present study, the Brixton test appears a useful addition to existing measures of executive functioning. Moreover, the test can be reliably applied in different groups of clinical patients. (JINS, 2009, 15, 695–703.)
Maternal psychological distress and fetal growth trajectories: The Generation R Study
- J. Henrichs, J. J. Schenk, S. J. Roza, M. P. van den Berg, H. G. Schmidt, E. A. P. Steegers, A. Hofman, V. W. V. Jaddoe, F. C. Verhulst, H. Tiemeier
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- Journal:
- Psychological Medicine / Volume 40 / Issue 4 / April 2010
- Published online by Cambridge University Press:
- 06 August 2009, pp. 633-643
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Background
Previous research suggests, though not consistently, that maternal psychological distress during pregnancy leads to adverse birth outcomes. We investigated whether maternal psychological distress affects fetal growth during the period of mid-pregnancy until birth.
MethodPregnant women (n=6313) reported levels of psychological distress using the Brief Symptom Inventory (anxious and depressive symptoms) and the Family Assessment Device (family stress) at 20.6 weeks pregnancy and had fetal ultrasound measurements in mid- and late pregnancy. Estimated fetal weight was calculated using head circumference, abdominal circumference and femur length.
ResultsIn mid-pregnancy, maternal distress was not linked to fetal size. In late pregnancy, however, anxious symptoms were related to fetal size after controlling for potential confounders. Anxious symptoms were also associated with a 37.73 g [95% confidence interval (CI) −69.22 to −6.25, p=0.019] lower birth weight. When we related maternal distress to fetal growth curves using multilevel models, more consistent results emerged. Maternal symptoms of anxiety or depression were associated with impaired fetal weight gain and impaired fetal head and abdominal growth. For example, depressive symptoms reduced fetal weight gain by 2.86 g (95% CI −4.48 to −1.23, p<0.001) per week.
ConclusionsThe study suggests that, starting in mid-pregnancy, fetal growth can be affected by different aspects of maternal distress. In particular, children of prenatally anxious mothers seem to display impaired fetal growth patterns during pregnancy. Future work should address the biological mechanisms underlying the association of maternal distress with fetal development and focus on the effects of reducing psychological distress in pregnancy.
Contributors
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- By Jennifer Alvarez, Ananda B. Amstadter, Metin Başoğlu, David M. Benedek, Charles C. Benight, George A. Bonanno, Evelyn J. Bromet, Richard A. Bryant, Barbara Lopes Cardozo, M. L. Somchai Chakkraband, Claude Chemtob, Roman Cieslak, Lauren M. Conoscenti, Joan M. Cook, Judith Cukor, Carla Kmett Danielson, JoAnn Difede, Charles DiMaggio, Anja J.E. Dirkzwager, Cristiane S. Duarte, Jon D. Elhai, Diane L. Elmore, Yael L.E. Errera, Julian D. Ford, Carol S. Fullerton, Sandro Galea, Freya Goodhew, Neil Greenberg, Lindsay Greene, Linda Grievink, Michael J. Gruber, Sumati Gupta, Johan M. Havenaar, Alesia O. Hawkins, Clare Henn-Haase, Kimberly Eaton Hoagwood, Christina W. Hoven, Sabra S. Inslicht, Krzysztof Kaniasty, Ronald C. Kessler, Rachel Kimerling, Richard V. King, Rolf J. Kleber, Jessica Mass Levitt, Brett T. Litz, Maria Livanou, Katelyn P. Mack, Paula Madrid, Shira Maguen, Paul Maguire, Donald J. Mandell, Charles R. Marmar, Andrea R. Maxwell, Shannon E. McCaslin, Alexander C. McFarlane, Thomas J. Metzler, Summer Nelson, Yuval Neria, Elana Newman, Thomas C. Neylan, Fran H. Norris, Carol S. North, Lawrence A. Palinkas, Benjaporn Panyayong, Maria Petukhova, Betty Pfefferbaum, Marleen Radigan, Beverley Raphael, James Rodriguez, G. James Rubin, Kenneth J. Ruggiero, Ebru Şalcıoğlu, Nancy A. Sampson, Arieh Y. Shalev, Bruce Shapiro, Laura M. Stough, Prawate Tantipiwatanaskul, Warunee Thienkrua, Phebe Tucker, J. Blake Turner, Robert J. Ursano, Bellis van den Berg, Peter G. van der Velden, Frits van Griensven, Miranda Van Hooff, Edward Waldrep, Philip S. Wang, Simon Wessely, Leslie H. Wind, C. Joris Yzermans, Heidi M. Zinzow
- Edited by Yuval Neria, Columbia University, New York, Sandro Galea, University of Michigan, Ann Arbor, Fran H. Norris
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- Book:
- Mental Health and Disasters
- Published online:
- 07 May 2010
- Print publication:
- 20 July 2009, pp xi-xvi
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Incidence of Helicoverpa armigera (Lepidoptera: Noctuidae) and its natural enemies on smallholder crops in Kenya
- H. van den Berg, M. J. W. Cock, G. I. Oduor, E. K. Onsongo
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- Bulletin of Entomological Research / Volume 83 / Issue 3 / September 1993
- Published online by Cambridge University Press:
- 10 July 2009, pp. 321-328
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Smallholder crops (sunflower, maize, sorghum and cotton) were grown in experimental plots at seven sites, representing different agricultural zones of Kenya, over four seasons. Helicoverpa armigera (Hübner) (formerly Heliothis armigera) only occasionally achieved population densities sufficient to cause obvious damage to the crops, and was virtually absent from the coastal sites. At the inland sites, infestation and mortality levels varied greatly. Information is presented on the incidence of H. armigera, and the identity, distribution and frequency of its common parasitoids and (potential) predators, sampled in the experimental plots. Trichogrammatoidea spp., egg parasitoids, and Linnaemya longirostris (Macquart), a tachinid late-larval parasitoid, were the most common parasitoid species, but total percentage parasitism was rather low. Of the large complex of predators, only anthocorids and ants (predominantly Pheidole spp., Myrmicaria spp. and Camponotus spp.) were sufficiently common and widespread to be of importance in suppressing H. armigera. The abundance of predators fluctuated widely between sites, but anthocorids were most abundant at the western sites.
12 - The Laplace transform: definition and properties
- R. J. Beerends, H. G. ter Morsche, Technische Universiteit Eindhoven, The Netherlands, J. C. van den Berg, Agricultural University, Wageningen, The Netherlands, E. M. van de Vrie, Open Universiteit
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- Fourier and Laplace Transforms
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- 05 June 2012
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- 07 August 2003, pp 267-287
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2 - Mathematical prerequisites
- R. J. Beerends, H. G. ter Morsche, Technische Universiteit Eindhoven, The Netherlands, J. C. van den Berg, Agricultural University, Wageningen, The Netherlands, E. M. van de Vrie, Open Universiteit
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- Fourier and Laplace Transforms
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- 05 June 2012
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- 07 August 2003, pp 27-56
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Summary
INTRODUCTION
In this chapter we present an overview of the necessary basic knowledge that will be assumed as mathematical prerequisite in the chapters to follow. It is presupposed that the reader already has previous knowledge of the subject matter in this chapter. However, it is advisable to read this chapter thoroughly, and not only because one may discover, and fill in, possible gaps in mathematical knowledge. This is because in Fourier and Laplace transforms one uses the complex numbers quite extensively; in general the functions that occur are complex-valued, sequences and series are sequences and series of complex numbers or of complex-valued functions, and power series are in general complex power series. In introductory courses one usually restricts the treatment of these subjects to real numbers and real functions. This will not be the case in the present chapter. Complex numbers will play a prominent role.
In section 2.1 the principal properties of the complex numbers are discussed, as well as the significance of the complex numbers for the zeros of polynomials. In section 2.2 partial fraction expansions are treated, which is a technique to convert a rational function into a sum of simple fractions. Section 2.3 contains a short treatment of differential and integral calculus for complex-valued functions, that is, functions which are defined on the real numbers, but whose function values may indeed be complex numbers. One will find, however, that the differential and integral calculus for complex-valued functions hardly differs from the calculus of real-valued functions.
14 - Applications of the Laplace transform
- R. J. Beerends, H. G. ter Morsche, Technische Universiteit Eindhoven, The Netherlands, J. C. van den Berg, Agricultural University, Wageningen, The Netherlands, E. M. van de Vrie, Open Universiteit
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- Fourier and Laplace Transforms
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- 05 June 2012
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- 07 August 2003, pp 310-336
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Summary
INTRODUCTION
The greater part of this chapter consists of section 14.1 on linear time-invariant continuous-time systems (LTC-systems). The Laplace transform is very well suited for the study of causal LTC-systems where switch-on phenomena occur as well: at time t = 0 ‘a switch is thrown’ and a process starts, while prior to time t = 0 the system was at rest. The input u(t) will thus be a causal signal and since the system is causal, the output y(t) will be causal as well. Applying the Laplace transform is then quite natural, especially since the Laplace transform exists for a large class of inputs u(t) as an ordinary integral in a certain half-plane Re s > ρ. This is in contrast to the Fourier transform, where distributions are needed more often. For the Laplace transform we can usually restrict the distribution theory to the delta functions δ(t − a) with a ≥ 0 (and their derivatives). As in chapter 10, the response h(t) to the delta function δ(t) again plays an important role. The Laplace transform H(s) of the impulse response is called the transfer function or system function. An LTC-system is then described in the s-domain by the simple relationship Y(s) = H(s)U(s), where Y(s) and U(s) are the Laplace transforms of, respectively, the output y(t) and the input u(t) (compare this with (10.6)).
17 - The Fast Fourier Transform
- R. J. Beerends, H. G. ter Morsche, Technische Universiteit Eindhoven, The Netherlands, J. C. van den Berg, Agricultural University, Wageningen, The Netherlands, E. M. van de Vrie, Open Universiteit
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- Fourier and Laplace Transforms
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- 05 June 2012
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- 07 August 2003, pp 375-390
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