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Exploring Decision-Making Strategies in the IOWA Gambling Task and Rat Gambling Task
- C. Hultman, N. Tjernström, S. Vadlin, M. Rehn, K. W. Nilsson, E. Roman, C. Åslund
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- Journal:
- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, pp. S106-S107
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Introduction
Impairments in decision-making processes are believed to play an important role in both substance use disorders and behavioral addictions. Clinical and pre-clinical experimental testing provide complimentary insights on the psychobiological mechanisms of decision-making. The IOWA Gambling Task (IGT) assesses decision-making under ambiguity and risk, in which individuals are faced with four card choices associated with varying monetary reinforcer/loss contingencies. The rat Gambling Task is a pre-clinical version using palatable reinforcers as wins and timeouts mimicking losses. However, studies with interspecies comparisons in these tasks are lacking, but important to facilitate translation of information that may help unravel the complex processes of decision-making and generate clinical advances.
ObjectivesThis study explores decision-making strategies among humans and rats performing the IGT and rGT.
MethodsA total of 270 young human adults performed a computerized version of the IGT, and 72 adult outbread male Lister Hooded rats performed the rGT. Performance was assessed and explored by normative scoring approaches and subgroup formations based on individual choices.
ResultsResults showed that most humans and rats learned to favor the advantageous choices, but the overall level of performance differed considerably. Humans displayed both exploration and learning as the task progressed, while rats showed relatively consistent pronounced preferences for the advantageous choices throughout the task. Nevertheless, variability in individual choice preferences during end performance were evident in both species.
ConclusionsResults are discussed in relation to procedural differences impacting performance and potential to study different aspects of decision-making. This is a first attempt to provide formal evaluation of similarities and differences regarding decision-making processes in the IGT and rGT from an explorative perspective.
Disclosure of InterestNone Declared
Public attitudes towards grief in animals
- N McGrath, J Walker, D Nilsson, C Phillips
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- Journal:
- Animal Welfare / Volume 22 / Issue 1 / February 2013
- Published online by Cambridge University Press:
- 01 January 2023, pp. 33-47
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Animals under human management are often separated from conspecifics, which may lead to behaviour indicative of separation distress or grief. For the purposes of this paper, grief is considered as a biological response to separation, indicated by a bi-phasic ‘protest-despair’ behavioural response. It is reasonable to assume that only animals which are able to form complex social bonds can experience grief. Scientific experiments have suggested that some farm and laboratory animals experience distress or grief as a result of maternal separation and social isolation. However, little is known about whether the public believe that animals are capable of grief. Therefore, we surveyed 1,000 members of the public to establish what knowledge they have about grief in animals and to compare this to what we know in science. The survey revealed that 90% of the general public believed that some or all animals can experience grief, with 23% believing that all animals can grieve. They attributed grief more to companion animals and animals with higher level cognitive abilities than to farm animals and animals that may be feared. It is concluded that public belief about grief in animals extends beyond scientific evidence, and that educating people about scientific findings and management practices connected with grief and separation distress may improve the welfare of farm and laboratory animals.
Milk intake and incident stroke and CHD in populations of European descent: a Mendelian randomisation study
- L. E. T. Vissers, I. Sluijs, S. Burgess, N. G. Forouhi, H. Freisling, F. Imamura, T. K. Nilsson, F. Renström, E. Weiderpass, K. Aleksandrova, C. C. Dahm, A. Perez-Cornago, M. B. Schulze, T. Y. N. Tong, D. Aune, C. Bonet, J. M. A. Boer, H. Boeing, M. D. Chirlaque, M. I. Conchi, L. Imaz, S. Jäger, V. Krogh, C. Kyrø, G. Masala, O. Melander, K. Overvad, S. Panico, M. J. Sánches, E. Sonestedt, A. Tjønneland, I. Tzoulaki, W. M. M. Verschuren, E. Riboli, N. J. Wareham, J. Danesh, A. S. Butterworth, Y. T. van der Schouw
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- Journal:
- British Journal of Nutrition / Volume 128 / Issue 9 / 14 November 2022
- Published online by Cambridge University Press:
- 21 October 2021, pp. 1789-1797
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- 14 November 2022
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Higher milk intake has been associated with a lower stroke risk, but not with risk of CHD. Residual confounding or reverse causation cannot be excluded. Therefore, we estimated the causal association of milk consumption with stroke and CHD risk through instrumental variable (IV) and gene-outcome analyses. IV analysis included 29 328 participants (4611 stroke; 9828 CHD) of the European Prospective Investigation into Cancer and Nutrition (EPIC)-CVD (eight European countries) and European Prospective Investigation into Cancer and Nutrition-Netherlands (EPIC-NL) case-cohort studies. rs4988235, a lactase persistence (LP) SNP which enables digestion of lactose in adulthood was used as genetic instrument. Intake of milk was first regressed on rs4988235 in a linear regression model. Next, associations of genetically predicted milk consumption with stroke and CHD were estimated using Prentice-weighted Cox regression. Gene-outcome analysis included 777 024 participants (50 804 cases) from MEGASTROKE (including EPIC-CVD), UK Biobank and EPIC-NL for stroke, and 483 966 participants (61 612 cases) from CARDIoGRAM, UK Biobank, EPIC-CVD and EPIC-NL for CHD. In IV analyses, each additional LP allele was associated with a higher intake of milk in EPIC-CVD (β = 13·7 g/d; 95 % CI 8·4, 19·1) and EPIC-NL (36·8 g/d; 95 % CI 20·0, 53·5). Genetically predicted milk intake was not associated with stroke (HR per 25 g/d 1·05; 95 % CI 0·94, 1·16) or CHD (1·02; 95 % CI 0·96, 1·08). In gene-outcome analyses, there was no association of rs4988235 with risk of stroke (OR 1·02; 95 % CI 0·99, 1·05) or CHD (OR 0·99; 95 % CI 0·95, 1·03). Current Mendelian randomisation analysis does not provide evidence for a causal inverse relationship between milk consumption and stroke or CHD risk.
Healthy ecosystems for human and animal health: Science diplomacy for responsible development in the Arctic: The Nordic Centre of Excellence, Clinf.org (Climate-change effects on the epidemiology of infectious diseases and the impacts on Northern societies)
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- B. Evengård, G. Destouni, Z. Kalantari, A. Albihn, C. Björkman, H. Bylund, E. Jenkins, A. Koch, N. Kukarenko, D. Leibovici, J. Lemmityinen, M. Menshakova, G. Mulvad, L.M. Nilsson, A. Omazic, N. Pshenichnaya, S. Quegan, A. Rautio, B. Revich, P. Rydén, A. Sjöstedt, N. Tokarevich, T. Thierfelder, D. Orlov
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- Polar Record / Volume 57 / 2021
- Published online by Cambridge University Press:
- 18 October 2021, e39
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Climate warming is occurring most rapidly in the Arctic, which is both a sentinel and a driver of further global change. Ecosystems and human societies are already affected by warming. Permafrost thaws and species are on the move, bringing pathogens and vectors to virgin areas. During a five-year project, the CLINF – a Nordic Center of Excellence, funded by the Nordic Council of Ministers, has worked with the One Health concept, integrating environmental data with human and animal disease data in predictive models and creating maps of dynamic processes affecting the spread of infectious diseases. It is shown that tularemia outbreaks can be predicted even at a regional level with a manageable level of uncertainty. To decrease uncertainty, rapid development of new and harmonised technologies and databases is needed from currently highly heterogeneous data sources. A major source of uncertainty for the future of contaminants and infectious diseases in the Arctic, however, is associated with which paths the majority of the globe chooses to follow in the future. Diplomacy is one of the most powerful tools Arctic nations have to influence these choices of other nations, supported by Arctic science and One Health approaches that recognise the interconnection between people, animals, plants and their shared environment at the local, regional, national and global levels as essential for achieving a sustainable development for both the Arctic and the globe.
Food intake in children and adolescents: a cross-sectional study from 2009/2010 to 2015/2016
- Maria N. Tell, Katarina Hedin, Mats Nilsson, Marie Golsäter, Hans Lingfors
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- Journal:
- Journal of Nutritional Science / Volume 10 / 2021
- Published online by Cambridge University Press:
- 15 July 2021, e51
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The aim was to describe food intake over time in children and adolescents, with respect to age and gender. The present study was a repeated cross-sectional study using self-reported data from a health questionnaire. Data were collected from the School Health Services in south-east Sweden from 44 297 students, 10, 13–14 and 16 years of age, 48 % girls and 52 % boys from 2009/2010 to 2015/2016. Reported intakes for eight foods were analysed in relation to the Nordic Nutrition Recommendations. Seventeen per cent of the students reported an intake in line with the recommendations for at least six of the eight foods fish, vegetables, fruit, mealtime beverages, juice/chocolate drinks, sugar-sweetened beverages, sweets/snacks and pastries. Intake of at least two fruits a day was the recommendation that was followed by the lowest proportion of students (30 %), and this result was stable over the study period. There was a gradual increase over time in the proportion of students who reported an intake in line with the recommendations. Younger students compared to older students, as well as girls compared to boys, reported intakes in line with the recommendations to a statistically significant larger extent. Few students reported intakes in line with the recommendations, although the quality of food intake seems to improve over time. The present results indicate a deterioration in reported food intake in the early years of adolescence. Finding methods to support all children and especially older adolescents to eat healthier, including eating more fruit, is of great importance to public health.
Environment and the serotonergic system
- L. Oreland, N. Nordquist, J. Hallman, J. Harro, K.W. Nilsson
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- European Psychiatry / Volume 25 / Issue 5 / June 2010
- Published online by Cambridge University Press:
- 16 April 2020, pp. 304-306
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In summary, genetics, as well as foetal and early life environmental factors shape the size or capacity of our monoamine systems, of which the serotonergic one might play a leading role. Those constitutional properties then form the biological basis for personality traits, such as impulsiveness and “sensation seeking”, which interact with psychosocial settings and life events to form a pattern of reactivity to a current life event or psychosocial situation, shown as a high or low order of magnitude of gene-environment interaction. In the present paper emphasis is put on the role of genotypes of the serotonin transporter, of monoamine oxidases A and B, and of platelet monoamine oxidase B activity, which all have been shown to be of importance for behaviour and with obvious effects of interactions with environment. Under unfortunate circumstances constitutional properties might be strong enough to result in vulnerability for suicide, even with a modest influence of environment.
A precessing and nutating jet in OJ287
- Silke Britzen, C. Fendt, G. Witzel, S.-J. Qian, I. N. Pashchenko, O. Kurtanidze, M. Zajacek, G. Martinez, V. Karas, M. Aller, H. Aller, A. Eckart, K. Nilsson, P. Arévalo, J. Cuadra, M. Subroweit, A. Witzel
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- Journal:
- Proceedings of the International Astronomical Union / Volume 14 / Issue S342 / May 2018
- Published online by Cambridge University Press:
- 07 April 2020, pp. 250-251
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- May 2018
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We re-analyzed OJ287 in 120 Very Long Baseline Array (VLBA, MOJAVE) observations (at 15 GHz) covering the time span between Apr. 1995 and Apr. 2017. We find that the radio jet motion over the sky is consistent with a precessing and nutating jet source. The variability of the radio flux-density can be explained by Doppler beaming due to a change in the viewing angle. We suggest that part of the optical emission is due to synchrotron emission related to the jet radiation. We find a strikingly similar scaling for the timescales for precession and nutation as indicated for SS433 with a factor of roughly 50 times longer in OJ287.
Altered hippocampal function in major depression despite intact structure and resting perfusion
- A. Finkelmeyer, J. Nilsson, J. He, L. Stevens, J. J. Maller, R. A. Moss, S. Small, P. Gallagher, K. Coventry, I. N. Ferrier, R. H. McAllister-Williams
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- Journal:
- Psychological Medicine / Volume 46 / Issue 10 / July 2016
- Published online by Cambridge University Press:
- 19 May 2016, pp. 2157-2168
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Background
Hippocampal volume reductions in major depression have been frequently reported. However, evidence for functional abnormalities in the same region in depression has been less clear. We investigated hippocampal function in depression using functional magnetic resonance imaging (fMRI) and neuropsychological tasks tapping spatial memory function, with complementing measures of hippocampal volume and resting blood flow to aid interpretation.
MethodA total of 20 patients with major depressive disorder (MDD) and a matched group of 20 healthy individuals participated. Participants underwent multimodal magnetic resonance imaging (MRI): fMRI during a spatial memory task, and structural MRI and resting blood flow measurements of the hippocampal region using arterial spin labelling. An offline battery of neuropsychological tests, including several measures of spatial memory, was also completed.
ResultsThe fMRI analysis showed significant group differences in bilateral anterior regions of the hippocampus. While control participants showed task-dependent differences in blood oxygen level-dependent (BOLD) signal, depressed patients did not. No group differences were detected with regard to hippocampal volume or resting blood flow. Patients showed reduced performance in several offline neuropsychological measures. All group differences were independent of differences in hippocampal volume and hippocampal blood flow.
ConclusionsFunctional abnormalities of the hippocampus can be observed in patients with MDD even when the volume and resting perfusion in the same region appear normal. This suggests that changes in hippocampal function can be observed independently of structural abnormalities of the hippocampus in depression.
Neurocognitive intra-individual variability in mood disorders: effects on attentional response time distributions
- P. Gallagher, J. Nilsson, A. Finkelmeyer, M. Goshawk, K. A. Macritchie, A. J. Lloyd, J. M. Thompson, R. J. Porter, A. H. Young, I. N. Ferrier, R. H. McAllister-Williams, S. Watson
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- Psychological Medicine / Volume 45 / Issue 14 / October 2015
- Published online by Cambridge University Press:
- 15 June 2015, pp. 2985-2997
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Background.
Attentional impairment is a core cognitive feature of major depressive disorder (MDD) and bipolar disorder (BD). However, little is known of the characteristics of response time (RT) distributions from attentional tasks. This is crucial to furthering our understanding of the profile and extent of cognitive intra-individual variability (IIV) in mood disorders.
Method.A computerized sustained attention task was administered to 138 healthy controls and 158 patients with a mood disorder: 86 euthymic BD, 33 depressed BD and 39 medication-free MDD patients. Measures of IIV, including individual standard deviation (iSD) and coefficient of variation (CoV), were derived for each participant. Ex-Gaussian (and Vincentile) analyses were used to characterize the RT distributions into three components: mu and sigma (mean and standard deviation of the Gaussian portion of the distribution) and tau (the ‘slow tail’ of the distribution).
Results.Compared with healthy controls, iSD was increased significantly in all patient samples. Due to minimal changes in average RT, CoV was only increased significantly in BD depressed patients. Ex-Gaussian modelling indicated a significant increase in tau in euthymic BD [Cohen's d = 0.39, 95% confidence interval (CI) 0.09–0.69, p = 0.011], and both sigma (d = 0.57, 95% CI 0.07–1.05, p = 0.025) and tau (d = 1.14, 95% CI 0.60–1.64, p < 0.0001) in depressed BD. The mu parameter did not differ from controls.
Conclusions.Increased cognitive variability may be a core feature of mood disorders. This is the first demonstration of differences in attentional RT distribution parameters between MDD and BD, and BD depression and euthymia. These data highlight the utility of applying measures of IIV to characterize neurocognitive variability and the great potential for future application.
Trapped-electron runaway effect
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- E. Nilsson, J. Decker, N. J. Fisch, Y. Peysson
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- Journal:
- Journal of Plasma Physics / Volume 81 / Issue 4 / August 2015
- Published online by Cambridge University Press:
- 28 April 2015, 475810403
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In a tokamak, trapped electrons subject to a strong electric field cannot run away immediately, because their parallel velocity does not increase over a bounce period. However, they do pinch toward the tokamak center. As they pinch toward the center, the trapping cone becomes more narrow, so eventually they can be detrapped and run away. When they run away, trapped electrons will have a very different signature from circulating electrons subject to the Dreicer mechanism. The characteristics of what are called trapped-electron runaways are identified and quantified, including their distinguishable perpendicular velocity spectrum and radial extent.
Authors' reply
- H. Georg Kuhn, Maria A. I. Åberg, Margda Waern, Jenny Nyberg, Michael Nilsson, Nancy L. Pedersen, Ylva Bergh, N. David Åberg, Kjell Torén
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- Journal:
- The British Journal of Psychiatry / Volume 202 / Issue 4 / April 2013
- Published online by Cambridge University Press:
- 02 January 2018, p. 311
- Print publication:
- April 2013
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Cardiovascular fitness in males at age 18 and risk of serious depression in adulthood: Swedish prospective population-based study
- Maria A. I. Åberg, Margda Waern, Jenny Nyberg, Nancy L. Pedersen, Ylva Bergh, N. David Åberg, Michael Nilsson, H. Georg Kuhn, Kjell Torén
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- Journal:
- The British Journal of Psychiatry / Volume 201 / Issue 5 / November 2012
- Published online by Cambridge University Press:
- 02 January 2018, pp. 352-359
- Print publication:
- November 2012
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Background
Studies suggest a role for cardiovascular fitness in the prevention of affective disorders.
AimsTo determine whether cardiovascular fitness at age 18 is associated with future risk of serious affective illness.
MethodPopulation-based Swedish cohort study of male conscripts (n = 1 117 292) born in 1950–1987 with no history of mental illness who were followed for 3–40 years. Data on cardiovascular fitness at conscription were linked with national hospital registers to calculate future risk of depression (requiring in-patient care) and bipolar disorder.
ResultsIn fully adjusted models low cardiovascular fitness was associated with increased risk for serious depression (hazard ratios (HR)=1.96, 95%, CI 1.71–2.23). No such association could be shown for bipolar disorder (HR=1.11, 95% CI 0.84–1.47).
ConclusionsLower cardiovascular fitness at age 18 was associated with increased risk of serious depression in adulthood. These results strengthen the theory of a cardiovascular contribution to the aetiology of depression.
Chapter 15 - Energy Supply Systems
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- By Robert N. Schock, World Energy Council, UK and Center for Global Security Research, Ralph Sims, Massey University, Stan Bull, National Renewable Energy Laboratory, Hans Larsen, Technical University, Vladimir Likhachev, Russian Academy of Sciences, Koji Nagano, Central Research Institute of Electric Power Industry, Hans Nilsson, FourFact, Seppo Vuori, VTT Technical Research Centre, Kurt Yeager, Electric Power Research Institute and Galvin Electricity Initiative, Li Zhou, Tsinghua University, Xiliang Zhang, Tsinghua University, John Weyant, Stanford University
- Global Energy Assessment Writing Team
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- Global Energy Assessment
- Published online:
- 05 September 2012
- Print publication:
- 27 August 2012, pp 1131-1172
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Summary
Executive Summary
A sustainable future depends on more efficient use of the Earth's abundant energy resources in order to meet the rapidly increasing demand for energy services as well as to provide broader access to everyone. In 2005 the overall efficiency of the energy system from primary energy to useful energy was only about 34%. Owing to diverse geographic inequities in both sources and people, supply cannot always meet the demand where needed. Energy pathways from source through conversion, transmission, storage, and distribution to end-users are complicated and presently consist of numerous discrete pathways that differ widely for each energy source and carrier. These include solid fuels, liquid fuels, gaseous fuels (including hydrogen), electricity and heat. Aging equipment, congested networks, and extreme demands complicate this picture in many countries of the Organisation for Economic Co-operation and Development (OECD). Development of new infrastructure in both non-OECD and OECD countries will lock-in future dependence on conventional or non-conventional energy sources. This chapter aims to assist decision-makers by providing up-todate knowledge on the full range of energy pathways, their management, and operation. Energy systems to achieve a sustainable future should be made much more flexible in order to deal with societal needs and the probable deployment of technologies not yet commercially available (such as smart appliances, electric vehicles, fuel cells, and carbon capture and storage). Technology and policy solutions are available for supporting more energy for sustainable development, but in order to meet the transition necessary to avoid unacceptable events such as social unrest and/or climate change driven temperature rise, they should be put in place rapidly, and done in concert with each other.
Larval morphology of genus Lancetes (Coleoptera: Adephaga: Dytiscidae): the hypothesis of sister-group relationship with the subfamily Dytiscinae revisited
- Yves Alarie, Miguel Archangelsky, Anders N. Nilsson, Chris H.S. Watts
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- Journal:
- The Canadian Entomologist / Volume 134 / Issue 4 / August 2002
- Published online by Cambridge University Press:
- 31 May 2012, pp. 467-501
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Descriptions of the larvae of Lancetes angusticollis (Curtis), L. lanceolatus (Clark), L. subseriatus Zimmermann, L. flavoscutatus Enderlein, L. delkeskampi Ríha, and L. nigriceps (Erichson) are provided. Characters from larval morphology are analyzed to infer the phylogenetic relationships of the genus Lancetes Sharp with other genera of Dytiscidae. A parsimony analysis based on 51 informative larval characteristics was conducted with the program NONA. The most parsimonious tree supports a sister-group relationship between the genus Lancetes and members of the subfamily Dytiscinae. The only unambiguous synapomorphy in support of this hypothesis is the secondary subdivision of some cephalic appendages. Other putative synapomorphies are the proximal articulation of the primary seta CO7 both on meso- and meta-coxa and the presence of additional primary setae on the ventral margin of the tibiae. Based on several character states including the presence of multifragmented urogomphi, the genus Lancetes is monophyletic.
THE HOLARCTIC SPECIES OF AGABUS (SENSU LATO) LEACH (COLEOPTERA: DYTISCIDAE)
- David J. Larson, Anders N. Nilsson
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- The Canadian Entomologist / Volume 117 / Issue 1 / January 1985
- Published online by Cambridge University Press:
- 31 May 2012, pp. 119-130
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The taxonomy, distribution, and ecology of the Holarctic species of Agabus (Coleoptera: Dytiscidae) are reviewed. Seventeen species occur in both the Nearctic and Palaearctic regions. The following new synonymy is proposed (valid name given last): A. solus Leech = A. adpressus Aubé; A. sharpi Jacobson and A. pseudoconfertus Wallis = A. opacus Aubé; A. kenaiensis Fall = A. wasastjernae (Sahlberg) and A. hudsonicus Leech = A. zaitzewi Poppius, thus each of these species is recognized for the first time as being Holarctic. The Nearctic species A. ontarionis Fall is reduced in status to a subspecies of A. fuscipennis (Payk.). Agabus congener (Thunb.) is redefined and Nearctic specimens formerly placed in the species are assigned to A. thomsoni (J. Sahlberg). The reports of Palaearctic occurrence of A. approximates Fall and A. discolor (Harris) are considered to be in error, the records referring to A. levanderi Hellén.
Larval morphology of the tribe Matini (Coleoptera: Dytiscidae, Colymbetinae): descriptions of Batrachomatus daemeli, Matus bicarinatus, and Allomatus nannup and phylogenetic relationships
- Yves Alarie, Chris H.S. Watts, Anders N. Nilsson
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- Journal:
- The Canadian Entomologist / Volume 133 / Issue 2 / April 2001
- Published online by Cambridge University Press:
- 31 May 2012, pp. 165-196
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Descriptions are presented of larval instars of three species of the colymbetine tribe Matini Zimmermann (Coleoptera: Dytiscidae), Batrachomatus daemeli (Sharp), Matus bicarinatus (Say), and Allomatus nannup Watts, including a chaetotaxic and porotaxic analysis of the cephalic capsule, head appendages, legs, last abdominal segment, and urogomphi. A parsimony analysis based on 32 informative larval characteristics was conducted with the computer program NONA. Members of the Matini are postulated to share a monophyletic origin based on (i) seta TR2 articulated anteroventroproximally on the trochanter; (ii) seta TR5 elongate on the metatrochanter; (iii) seta TA1 elongate and inserted proximally on the tarsus; (iv) antenomere III with a hole-like ventroapical spinula; (v) prementum with the primary setae LA2, LA3, LA4, LA5, and LA8 spine-like and elongate; (vi) presence of secondary setae on the cephalic appendages; and (vii) presence of additional primary setae on the last abdominal segment. A clade Matini + Colymbetini is postulated based on (i) metafemoral seta FE5; (ii) metafemoral seta FE6; (iii) seta TI6 on tibia, all elongate and hair-like; (iv) one-segmented urogomphus; (v) presence of an occipital suture in first instar; (vi) galea elongate; (vii) presence of natatory setae on legs; and (viii) presence of secondary setae on the urogomphus.
Mechanical Properties and Magnetism: Stainless Steel Alloys from First-principles Theory
- L. Vitos, H. L. Zhang, N. Al-Zoubi, S. Lu, J.-O. Nilsson, S. Hertzman, B. Johansson
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- Journal:
- MRS Online Proceedings Library Archive / Volume 1296 / 2011
- Published online by Cambridge University Press:
- 27 September 2011, mrsf10-1296-o02-01
- Print publication:
- 2011
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Stainless steels are among the most important engineering materials, finding their principal scope in industry, specifically in cutlery, food production, storage, architecture, medical equipment, etc. Austenitic stainless steels form the largest sub-category of stainless steels having as the main building blocks the paramagnetic substitutional disordered Fe-Cr-Ni-based alloys. Because of that, austenitic steels represent the primary choice for non-magnetic engineering materials. The presence of the chemical and magnetic disorder hindered any previous attempt to calculate the fundamental electronic, structural and mechanical properties of austenitic stainless steels from first-principles theories. Our ability to reach an ab initio atomistic level approach in this exciting field has become possible by the Exact Muffin-Tin Orbitals (EMTO) method. This method, in combination with the coherent potential approximation, has proved an accurate tool in the description of the concentrated random alloys. Using the EMTO method, we presented an insight to the electronic and magnetic structure, and micromechanical properties of austenitic stainless steel alloys. In the present contribution, we will discuss the role of magnetism on the stacking fault energies and elastic properties of paramagnetic Fe-based alloys.
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. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- Book:
- The Cambridge Dictionary of Christianity
- Published online:
- 05 August 2012
- Print publication:
- 20 September 2010, pp xi-xliv
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Preference for Sex of the Child Among Pregnant Women
- N. Uddenberg, P.-E. Almgren, Å. Nilsson
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- Journal of Biosocial Science / Volume 3 / Issue 3 / July 1971
- Published online by Cambridge University Press:
- 31 July 2008, pp. 267-280
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One hundred and fifty-two randomly selected pregnant women were examined and followed up by interviews and psychological tests during pregnancy and after parturition. The present paper is focused upon factors which determine the woman's preference for the sex of her expected child. It was shown that women who already have one or more children generally wanted the expected child to be of the opposite sex to her youngest child. Thus, the main part of the study was limited to eighty-one nulliparous women.
Associations were found between the woman's preference for the sex of the child and several factors such as the sex of her own siblings and her position among them, her education, intelligence and degree of field-dependence indicating immaturity and lack of autonomy.
Several of the findings presented refute the common supposition that nulliparous women generally want to give birth to a son, and that the arrival of a son is more satisfactory. Women wishing for a son were found to be somewhat more field-dependent than other women and somewhat more often reported that they had experienced a range of mental symptoms before the current pregnancy. Women wishing for a boy also reported more mental symptoms during the post-partum period. Moreover, those women who gave birth to a son reperted more symptoms at this time than those who gave birth to a daughter, and paradoxically the most affected were those who had wished for a son and had had their wishes fulfilled. The arrival of a daughter therefore seems to be equally satisfactory to the mother, at least as measured by the criteria used in this investigation.
6 - Hematopoietic microenvironment and age
- from Part II - Hematopoiesis
- Edited by Lodovico Balducci, William Ershler, Giovanni de Gaetano
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- Blood Disorders in the Elderly
- Published online:
- 21 October 2009
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- 20 December 2007, pp 71-83
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Summary
Introduction
Considerable evidence supports the concept that the localization of hematopoiesis to the bone marrow (BM) in adult mammals involves developmentally regulated interactions between primitive hematopoietic stem cells (HSCs) and the stromal cell-mediated hematopoietic microenvironment (HM) of the marrow. Moreover, it is well accepted that stromal cells and their extracellular biosynthetic products play a critical role in many aspects of hematopoiesis including the regulation, recruitment, and retention of hematopoietic stem and progenitor cells within preferred sites of the BM. Therefore, conceptually at least, there are two key cellular components for consideration when discussing the effects of aging on hematopoiesis: first the hematopoietic stem and progenitor cells themselves, and second those cells that comprise the hematopoietic microenvironment. In this chapter we review the current understanding of what constitutes the HM and how its components and functions change during aging and thereby impact specifically on primitive hematopoietic progenitor cells and hematopoiesis. In the final section, we highlight the unresolved questions concerning the effect of age on the HM and suggest a series of studies to further our understanding of this biology. Finally, we acknowledge the publications and contributions made by many investigators over the last four decades or more, and apologize to those whose work we may have inadvertently not referenced in this review.