Dynamic heterogeneity and life history variability in the kittiwake

DEFF Research Database (Denmark)

Steiner, Uli; Tuljapurkar, Shripad; Orzack, Steven Hecht

2010-01-01

1. Understanding the evolution of life histories requires an assessment of the process that generates variation in life histories. Within-population heterogeneity of life histories can be dynamically generated by stochastic variation of reproduction and survival or be generated by individual...... differences that are fixed at birth. 2. We show for the kittiwake that dynamic heterogeneity is a sufficient explanation of observed variation of life histories. 3. The total heterogeneity in life histories has a small contribution from reproductive stage dynamics and a large contribution from survival...... differences. We quantify the diversity in life histories by metrics computed from the generating stochastic process. 4. We show how dynamic heterogeneity can be used as a null model and also how it can lead to positive associations between reproduction and survival across the life span. 5. We believe our...

Globalization and Life History Research: Fragments of a Life Foretold

Science.gov (United States)

Tierney, William G.

2010-01-01

The goal of this paper is to understand, by way of a life history of one low-income working-class youth, how globalization impacts the working class in a developing nation. The concept of globalization and the method of life history seem diametrically opposed. Globalization is an idea about large social forces that impact the economic and material…

[End-of-life care and end-of-life medical decisions: the ITAELD study].

Science.gov (United States)

Miccinesi, Guido; Puliti, Donella; Paci, Eugenio

2011-01-01

To describe the attitudes towards end of life care and the practice of end-of-life medical decisions with possible life-shortening effect among Italian physicians. Cross sectional study (last death among the assisted patients in the last 12 months was considered). In the year 2007, 5,710 GPs and 8,950 hospital physicians were invited all over Italy to participate in the ITAELDstudy through anonymous mail questionnaire. Proportion of agreement with statements on end-of-life care issues. Proportion of deaths with an end-of-life medical decision. The response rate was 19.2%. The 65% of respondents agreed with the duty to respect any non-treatment request of the competent patient, the 55% agreed with the same duty in case of advanced directives, the 39% in case of proxy's request. The 53% of respondents agreed with the ethical acceptability of active euthanasia in selected cases. Among 1,850 deaths the 57.7% did not receive any end-of-life medical decision. For a further 21.0% no decision was possible, being sudden and unexpected deaths. In the remaining 21.3% at least one end-of-life medical decision was reported: 0.8% was classified as physician assisted death, 20.5% as non-treatment decision. Among all deceased the 19.6% were reported to have been deeply sedated. Being favourable to the use of opioids in terminal patients was associated to non-treatment decisions with possible but non-intentional life shortening effect; agreeing with the duty to fully respect any actual non-treatment request of the competent patient was associated to end-of life medical decisions with intentional life-shortening effect (adjusted OR>10 in both cases). The life stance and ethical beliefs of physicians determine their behaviour at the end of life wherever specific statements of law are lacking. Therefore education and debate are needed on these issues.

Effects of nocturnal illumination on life-history decisions and fitness in two wild songbird species.

Science.gov (United States)

de Jong, Maaike; Ouyang, Jenny Q; Da Silva, Arnaud; van Grunsven, Roy H A; Kempenaers, Bart; Visser, Marcel E; Spoelstra, Kamiel

2015-05-05

The effects of artificial night lighting on animal behaviour and fitness are largely unknown. Most studies report short-term consequences in locations that are also exposed to other anthropogenic disturbance. We know little about how the effects of nocturnal illumination vary with different light colour compositions. This is increasingly relevant as the use of LED lights becomes more common, and LED light colour composition can be easily adjusted. We experimentally illuminated previously dark natural habitat with white, green and red light, and measured the effects on life-history decisions and fitness in two free-living songbird species, the great tit (Parus major) and pied flycatcher (Ficedula hypoleuca) in two consecutive years. In 2013, but not in 2014, we found an effect of light treatment on lay date, and of the interaction of treatment and distance to the nearest lamp post on chick mass in great tits but not in pied flycatchers. We did not find an effect in either species of light treatment on breeding densities, clutch size, probability of brood failure, number of fledglings and adult survival. The finding that light colour may have differential effects opens up the possibility to mitigate negative ecological effects of nocturnal illumination by using different light spectra. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Life history dependent morphometric variation in stream-dwelling Atlantic salmon

Science.gov (United States)

Letcher, B.H.

2003-01-01

The time course of morphometric variation among life histories for stream-dwelling Atlantic salmon (Salmo salar L.) parr (age-0+ to age-2+) was analyzed. Possible life histories were combinations of parr maturity status in the autumn (mature or immature) and age at outmigration (smolt at age-2+ or later age). Actual life histories expressed with enough fish for analysis in the 1997 cohort were immature/age-2+ smolt, mature/age-2 +smolt, and mature/age-2+ non-smolt. Tagged fish were assigned to one of the three life histories and digital pictures from the field were analyzed using landmark-based geometric morphometrics. Results indicated that successful grouping of fish according to life history varied with fish age, but that fish could be grouped before the actual expression of the life histories. By March (age-1+), fish were successfully grouped using a descriptive discriminant function and successful assignment ranged from 84 to 97% for the remainder of stream residence. A jackknife of the discriminant function revealed an average life history prediction success of 67% from age-1+ summer to smolting. Low sample numbers for one of the life histories may have limited prediction success. A MANOVA on the shape descriptors (relative warps) also indicated significant differences in shape among life histories from age-1+ summer through to smolting. Across all samples, shape varied significantly with size. Within samples, shape did not vary significantly with size for samples from December (age-0+) to May (age-1+). During the age-1+ summer however, shape varied significantly with size, but the relationship between shape and size was not different among life histories. In the autumn (age-1+) and winter (age-2+), life history differences explained a significant portion of the change in shape with size. Life history dependent morphometric variation may be useful to indicate the timing of early expressions of life history variation and as a tool to explore temporal and

Competence and Quality in Real-Life Decision Making.

Science.gov (United States)

Geisler, Martin; Allwood, Carl Martin

2015-01-01

What distinguishes a competent decision maker and how should the issue of decision quality be approached in a real-life context? These questions were explored in three studies. In Study 1, using a web-based questionnaire and targeting a community sample, we investigated the relationships between objective and subjective indicators of real-life decision-making success. In Study 2 and 3, targeting two different samples of professionals, we explored if the prevalent cognitively oriented definition of decision-making competence could be beneficially expanded by adding aspects of competence in terms of social skills and time-approach. The predictive power for each of these three aspects of decision-making competence was explored for different indicators of real-life decision-making success. Overall, our results suggest that research on decision-making competence would benefit by expanding the definition of competence, by including decision-related abilities in terms of social skills and time-approach. Finally, the results also indicate that individual differences in real-life decision-making success profitably can be approached and measured by different criteria.

Competence and Quality in Real-Life Decision Making

Science.gov (United States)

2015-01-01

What distinguishes a competent decision maker and how should the issue of decision quality be approached in a real-life context? These questions were explored in three studies. In Study 1, using a web-based questionnaire and targeting a community sample, we investigated the relationships between objective and subjective indicators of real-life decision-making success. In Study 2 and 3, targeting two different samples of professionals, we explored if the prevalent cognitively oriented definition of decision-making competence could be beneficially expanded by adding aspects of competence in terms of social skills and time-approach. The predictive power for each of these three aspects of decision-making competence was explored for different indicators of real-life decision-making success. Overall, our results suggest that research on decision-making competence would benefit by expanding the definition of competence, by including decision-related abilities in terms of social skills and time-approach. Finally, the results also indicate that individual differences in real-life decision-making success profitably can be approached and measured by different criteria. PMID:26545239

Assessment of decisions in the context of life attitudes

Directory of Open Access Journals (Sweden)

Klamut Ryszard

2012-01-01

Full Text Available Presented article attempts to show sense of life perspective as a determinant of decision making. It is assumed that the sense of life perspective described as life attitudes is significant in assessment of decision problem defined in the predecision phase of the decision making process. The predicted dependence was analysed in three categories of decision: self-development, financial and voting. The research was conducted on two groups of 186 and 86 participants. Two methods were used in the research: the Life Attitude Profile -Revised (LAP-R and the Decision Assessment Questionnaire. In statistical analysis, the canonical correlation analysis was used. The scores show that the life attitudes (especially: Purpose, Coherence, Life Control and Existential Vacuum are correlated with the assessment factor (especially: Cognitive Analysis and Affective Assessment of each tested category of decision. However, the most significant relationship is found in the self-development decision.

Invader population speeds up life history during colonization

OpenAIRE

Amundsen, Per-Arne; Salonen, Erno; Niva, Teuvo; Gjelland, Karl Øystein; Præbel, Kim; Sandlund, Odd Terje; Knudsen, Rune; Bøhn, Thomas

2012-01-01

We explore the long-term developments in population biology and life history during the invasion and establishment of the fish species vendace Coregonus albula in a subarctic watercourse by comparing life-history traits and molecular genetic estimates between the source and the colonist population. The two populations exhibited highly contrasting life-history strategies. Relative to the source population, the colonist population was characterized by slower somatic growth rates, earlier sexual...

Interspecific variation in life history relates to antipredator decisions by marine mesopredators on temperate reefs.

Directory of Open Access Journals (Sweden)

Alejandro Frid

Full Text Available As upper-level predatory fishes become overfished, mesopredators rise to become the new 'top' predators of over-exploited marine communities. To gain insight into ensuing mechanisms that might alter indirect species interactions, we examined how behavioural responses to an upper-level predatory fish might differ between mesopredator species with different life histories. In rocky reefs of the northeast Pacific Ocean, adult lingcod (Ophiodon elongatus are upper-level predators that use a sit-and-wait hunting mode. Reef mesopredators that are prey to adult lingcod include kelp greenling (Hexagrammos decagrammus, younger lingcod, copper rockfish (Sebastes caurinus and quillback rockfish (S. maliger. Across these mesopredators species, longevity and age at maturity increases and, consequently, the annual proportion of lifetime reproductive output decreases in the order just listed. Therefore, we hypothesized that the level of risk taken to acquire resources would vary interspecifically in that same order. During field experiments we manipulated predation risk with a model adult lingcod and used fixed video cameras to quantify interactions between mesopredators and tethered prey (Pandalus shrimps. We predicted that the probabilities of inspecting and attacking tethered prey would rank from highest to lowest and the timing of these behaviours would rank from earliest to latest as follows: kelp greenling, lingcod, copper rockfish, and quillback rockfish. We also predicted that responses to the model lingcod, such as avoidance of interactions with tethered prey, would rank from weakest to strongest in the same order. Results were consistent with our predictions suggesting that, despite occupying similar trophic levels, longer-lived mesopredators with late maturity have stronger antipredator responses and therefore experience lower foraging rates in the presence of predators than mesopredators with faster life histories. The corollary is that the fishery

Interspecific variation in life history relates to antipredator decisions by marine mesopredators on temperate reefs.

Science.gov (United States)

Frid, Alejandro; Marliave, Jeff; Heithaus, Michael R

2012-01-01

As upper-level predatory fishes become overfished, mesopredators rise to become the new 'top' predators of over-exploited marine communities. To gain insight into ensuing mechanisms that might alter indirect species interactions, we examined how behavioural responses to an upper-level predatory fish might differ between mesopredator species with different life histories. In rocky reefs of the northeast Pacific Ocean, adult lingcod (Ophiodon elongatus) are upper-level predators that use a sit-and-wait hunting mode. Reef mesopredators that are prey to adult lingcod include kelp greenling (Hexagrammos decagrammus), younger lingcod, copper rockfish (Sebastes caurinus) and quillback rockfish (S. maliger). Across these mesopredators species, longevity and age at maturity increases and, consequently, the annual proportion of lifetime reproductive output decreases in the order just listed. Therefore, we hypothesized that the level of risk taken to acquire resources would vary interspecifically in that same order. During field experiments we manipulated predation risk with a model adult lingcod and used fixed video cameras to quantify interactions between mesopredators and tethered prey (Pandalus shrimps). We predicted that the probabilities of inspecting and attacking tethered prey would rank from highest to lowest and the timing of these behaviours would rank from earliest to latest as follows: kelp greenling, lingcod, copper rockfish, and quillback rockfish. We also predicted that responses to the model lingcod, such as avoidance of interactions with tethered prey, would rank from weakest to strongest in the same order. Results were consistent with our predictions suggesting that, despite occupying similar trophic levels, longer-lived mesopredators with late maturity have stronger antipredator responses and therefore experience lower foraging rates in the presence of predators than mesopredators with faster life histories. The corollary is that the fishery removal of top

The rate-size trade-off structures intraspecific variation in Daphnia ambigua life history parameters.

Science.gov (United States)

DeLong, John P; Hanley, Torrance C

2013-01-01

The identification of trade-offs is necessary for understanding the evolution and maintenance of diversity. Here we employ the supply-demand (SD) body size optimization model to predict a trade-off between asymptotic body size and growth rate. We use the SD model to quantitatively predict the slope of the relationship between asymptotic body size and growth rate under high and low food regimes and then test the predictions against observations for Daphnia ambigua. Close quantitative agreement between observed and predicted slopes at both food levels lends support to the model and confirms that a 'rate-size' trade-off structures life history variation in this population. In contrast to classic life history expectations, growth and reproduction were positively correlated after controlling for the rate-size trade-off. We included 12 Daphnia clones in our study, but clone identity explained only some of the variation in life history traits. We also tested the hypothesis that growth rate would be positively related to intergenic spacer length (i.e. the growth rate hypothesis) across clones, but we found that clones with intermediate intergenic spacer lengths had larger asymptotic sizes and slower growth rates. Our results strongly support a resource-based optimization of body size following the SD model. Furthermore, because some resource allocation decisions necessarily precede others, understanding interdependent life history traits may require a more nested approach.

The rate-size trade-off structures intraspecific variation in Daphnia ambigua life history parameters.

Directory of Open Access Journals (Sweden)

John P DeLong

Full Text Available The identification of trade-offs is necessary for understanding the evolution and maintenance of diversity. Here we employ the supply-demand (SD body size optimization model to predict a trade-off between asymptotic body size and growth rate. We use the SD model to quantitatively predict the slope of the relationship between asymptotic body size and growth rate under high and low food regimes and then test the predictions against observations for Daphnia ambigua. Close quantitative agreement between observed and predicted slopes at both food levels lends support to the model and confirms that a 'rate-size' trade-off structures life history variation in this population. In contrast to classic life history expectations, growth and reproduction were positively correlated after controlling for the rate-size trade-off. We included 12 Daphnia clones in our study, but clone identity explained only some of the variation in life history traits. We also tested the hypothesis that growth rate would be positively related to intergenic spacer length (i.e. the growth rate hypothesis across clones, but we found that clones with intermediate intergenic spacer lengths had larger asymptotic sizes and slower growth rates. Our results strongly support a resource-based optimization of body size following the SD model. Furthermore, because some resource allocation decisions necessarily precede others, understanding interdependent life history traits may require a more nested approach.

End-of-life decisions in the intensive care unit

DEFF Research Database (Denmark)

Jensen, Hanne Irene

2012-01-01

be interdisciplinary, but the literature shows that this is not always the case. Research on end-of-life issues in Danish ICUs is limited. Aim The aims of this thesis were to • Examine Danish practices regarding end-of-life decisions in the ICU. • Examine the opinions of nurses and physicians who work in Danish ICUs...... and decision-making. Hypotheses • Nurses, intensivists, and primary physicians have different experiences of interdisciplinary collaboration regarding end-of-life decision-making in the ICU. • Specific interventions targeting end-of-life decision-making in the ICU, such as interdisciplinary audits......Background When making end-of-life decisions in intensive care units, the different staff groups have different roles in the decision-making process and may not always assess the situation identically. Practice recommendations for withholding or withdrawing therapy state that decisions should...

Towards cancer-aware life-history modelling.

Science.gov (United States)

Kokko, Hanna; Hochberg, Michael E

2015-07-19

Studies of body size evolution, and life-history theory in general, are conducted without taking into account cancer as a factor that can end an organism's reproductive lifespan. This reflects a tacit assumption that predation, parasitism and starvation are of overriding importance in the wild. We argue here that even if deaths directly attributable to cancer are a rarity in studies of natural populations, it remains incorrect to infer that cancer has not been of importance in shaping observed life histories. We present first steps towards a cancer-aware life-history theory, by quantifying the decrease in the length of the expected reproductively active lifespan that follows from an attempt to grow larger than conspecific competitors. If all else is equal, a larger organism is more likely to develop cancer, but, importantly, many factors are unlikely to be equal. Variations in extrinsic mortality as well as in the pace of life--larger organisms are often near the slow end of the fast-slow life-history continuum--can make realized cancer incidences more equal across species than what would be observed in the absence of adaptive responses to cancer risk (alleviating the so-called Peto's paradox). We also discuss reasons why patterns across species can differ from within-species predictions. Even if natural selection diminishes cancer susceptibility differences between species, within-species differences can remain. In many sexually dimorphic cases, we predict males to be more cancer-prone than females, forming an understudied component of sexual conflict.

Life History Strategy and Disordered Eating Behavior

Directory of Open Access Journals (Sweden)

Catherine Salmon

2009-10-01

Full Text Available A sample of female undergraduates completed a packet of questionnaires consisting of the Arizona Life History Battery, a modified version of the Eating Disorders Inventory, the Behavioral Regulation scales from the Behavior Rating Inventory of Executive Function, and two measures of Female Intrasexual Competitiveness that distinguished between competition for mates and competition for status. As predicted, Executive Functions completely mediated the relation between Slow Life History Strategy and Disordered Eating Behavior. Surprisingly, however, the relation between Female Intrasexual Competitiveness (competition for mates and competition for status and Disordered Eating Behavior was completely spurious, with executive functions serving as a common cause underlying the inhibition of both Disordered Eating Behavior and Female Intrasexual Competitiveness. The protective function of Slow Life History Strategy with respect to Disordered Eating Behavior apparently resides in a higher degree of Behavioral Regulation, a type of Executive Function. The enhanced Behavioral Regulation or self-control, of individuals with a Slow Life History Strategy is also protective against hazardously escalated levels of Female Intrasexual Competitiveness.

Rules of Thumb in Life-Cycle Saving Decisions

OpenAIRE

Winter, Joachim; Schlafmann, Kathrin; Rodepeter, Ralf

2011-01-01

We analyse life-cycle saving decisions when households use simple heuristics, or rules of thumb, rather than solve the underlying intertemporal optimization problem. We simulate life-cycle saving decisions using three simple rules and compute utility losses relative to the solution of the optimization problem. Our simulations suggest that utility losses induced by following simple decision rules are relatively low. Moreover, the two main saving motives re ected by the canonical life-cyc...

Variability in the developmental life history of the genus Gorilla.

Science.gov (United States)

Stoinski, Tara S; Perdue, Bonnie; Breuer, Thomas; Hoff, Michael P

2013-10-01

Life history is influenced by factors both intrinsic (e.g., body and relative brain size) and extrinsic (e.g., diet, environmental instability) to organisms. In this study, we examine the prediction that energetic risk influences the life history of gorillas. Recent comparisons suggest that the more frugivorous western lowland gorilla shows increased infant dependence, and thus a slower life history, than the primarily folivorous mountain gorilla to buffer against the risk of starvation during periods of food unpredictability. We further tested this hypothesis by incorporating additional life history data from wild western lowland gorillas and captive western lowland gorillas with the assumption that the latter live under ecological conditions of energetic risk that more closely resemble those of mountain gorillas and thus should show faster life histories than wild members of the species. Overall, we found captive western lowland and wild mountain gorillas to have faster developmental life histories than wild western lowland gorillas, weaning their infants approximately a year earlier and thus reducing interbirth intervals by a year. These results provide support that energetic risk plays an important role in determining gorilla life history. Unlike previous assertions, gorillas do not have substantially faster life histories, at least at the genus level, than other great apes. This calls for a re-evaluation of theories concerning comparative ape life history and evolution and highlights the need for data from additional populations that vary in energetic risk. Copyright © 2013 Wiley Periodicals, Inc.

Parasitism shaping host life-history evolution

DEFF Research Database (Denmark)

Fredensborg, Brian Lund; Poulin, R

2006-01-01

1. Variation in life-history strategies among conspecific populations indicates the action of local selective pressures; recently, parasitism has been suggested as one of these local forces. 2. Effects of trematode infections on reproductive effort, juvenile growth, size at maturity and susceptib......1. Variation in life-history strategies among conspecific populations indicates the action of local selective pressures; recently, parasitism has been suggested as one of these local forces. 2. Effects of trematode infections on reproductive effort, juvenile growth, size at maturity...

Multistate analysis of life histories with R

CERN Document Server

Willekens, Frans

2014-01-01

This book provides an introduction to multistate event history analysis. It is an extension of survival analysis, in which a single terminal event (endpoint) is considered and the time-to-event is studied. Multistate models focus on life histories or trajectories, conceptualized as sequences of states and sequences of transitions between states. Life histories are modeled as realizations of continuous-time Markov processes. The model parameters, transition rates, are estimated from data on event counts and populations at risk, using the statistical theory of counting processes. The Comprehensive R Network Archive (CRAN) includes several packages for multistate modeling. This book is about Biograph. The package is designed to (a) enhance exploratory analysis of life histories and (b) make multistate modeling accessible. The package incorporates utilities that connect to several packages for multistate modeling, including survival, eha, Epi, mvna, etm, mstate, msm, and TraMineR for sequence analysis. The book ...

Oxidative stress and life histories: unresolved issues and current needs

OpenAIRE

Speakman, John R.; Blount, Jonathan D.; Bronikowski, Anne M.; Buffenstein, Rochelle; Isaksson, Caroline; Kirkwood, Tom B. L.; Monaghan, Pat; Ozanne, Susan E.; Beaulieu, Micha?l; Briga, Michael; Carr, Sarah K.; Christensen, Louise L.; Cochem?, Helena M.; Cram, Dominic L.; Dantzer, Ben

2015-01-01

Abstract Life?history theory concerns the trade?offs that mold the patterns of investment by animals between reproduction, growth, and survival. It is widely recognized that physiology plays a role in the mediation of life?history trade?offs, but the details remain obscure. As life?history theory concerns aspects of investment in the soma that influence survival, understanding the physiological basis of life histories is related, but not identical, to understanding the process of aging. One i...

Oxidative stress and life histories : Unresolved issues and current needs

NARCIS (Netherlands)

Speakman, John R.; Blount, Jonathan D.; Bronikowski, Anne M.; Buffenstein, Rochelle; Isaksson, Caroline; Kirkwood, Tom B. L.; Monaghan, Pat; Ozanne, Susan E.; Beaulieu, Michael; Briga, Michael; Carr, Sarah K.; Christensen, Louise L.; Cocheme, Helena M.; Cram, Dominic L.; Dantzer, Ben; Harper, Jim M.; Jurk, Diana; King, Annette; Noguera, Jose C.; Salin, Karine; Sild, Elin; Simons, Mirre J. P.; Smith, Shona; Stier, Antoine; Tobler, Michael; Vitikainen, Emma; Peaker, Malcolm; Selman, Colin

2015-01-01

Life-history theory concerns the trade-offs that mold the patterns of investment by animals between reproduction, growth, and survival. It is widely recognized that physiology plays a role in the mediation of life-history trade-offs, but the details remain obscure. As life-history theory concerns

Life-History Patterns of Lizards of the World.

Science.gov (United States)

Mesquita, Daniel O; Costa, Gabriel C; Colli, Guarino R; Costa, Taís B; Shepard, Donald B; Vitt, Laurie J; Pianka, Eric R

2016-06-01

Identification of mechanisms that promote variation in life-history traits is critical to understand the evolution of divergent reproductive strategies. Here we compiled a large life-history data set (674 lizard populations, representing 297 species from 263 sites globally) to test a number of hypotheses regarding the evolution of life-history traits in lizards. We found significant phylogenetic signal in most life-history traits, although phylogenetic signal was not particularly high. Climatic variables influenced the evolution of many traits, with clutch frequency being positively related to precipitation and clutches of tropical lizards being smaller than those of temperate species. This result supports the hypothesis that in tropical and less seasonal climates, many lizards tend to reproduce repeatedly throughout the season, producing smaller clutches during each reproductive episode. Our analysis also supported the hypothesis that viviparity has evolved in lizards as a response to cooler climates. Finally, we also found that variation in trait values explained by clade membership is unevenly distributed among lizard clades, with basal clades and a few younger clades showing the most variation. Our global analyses are largely consistent with life-history theory and previous results based on smaller and scattered data sets, suggesting that these patterns are remarkably consistent across geographic and taxonomic scales.

Life history evolution in social insects : A female perspective

NARCIS (Netherlands)

Negroni, Matteo Antoine; Jongepier, Evelien; Feldmeyer, Barbara; Kramer, Boris H.; Foitzik, Susanne

2016-01-01

Social insects are known for their unusual life histories with fecund, long-lived queens and sterile, short-lived workers. We review ultimate factors underlying variation in life history strategies in female social insects, whose social life reshapes common trade-offs, such as the one between

Life History Trade-offs

NARCIS (Netherlands)

Smallegange, I.M.; Kliman, R.M.

2016-01-01

Trade-offs play a central role in life history theory. This article explains why they exist, how they arise, how they can be measured, and briefly discusses their evolution. Three important trade-offs are discussed in detail: the trade-off between current reproduction and survival, between current

Oxidative stress and life histories: unresolved issues and current needs.

Science.gov (United States)

Speakman, John R; Blount, Jonathan D; Bronikowski, Anne M; Buffenstein, Rochelle; Isaksson, Caroline; Kirkwood, Tom B L; Monaghan, Pat; Ozanne, Susan E; Beaulieu, Michaël; Briga, Michael; Carr, Sarah K; Christensen, Louise L; Cochemé, Helena M; Cram, Dominic L; Dantzer, Ben; Harper, Jim M; Jurk, Diana; King, Annette; Noguera, Jose C; Salin, Karine; Sild, Elin; Simons, Mirre J P; Smith, Shona; Stier, Antoine; Tobler, Michael; Vitikainen, Emma; Peaker, Malcolm; Selman, Colin

2015-12-01

Life-history theory concerns the trade-offs that mold the patterns of investment by animals between reproduction, growth, and survival. It is widely recognized that physiology plays a role in the mediation of life-history trade-offs, but the details remain obscure. As life-history theory concerns aspects of investment in the soma that influence survival, understanding the physiological basis of life histories is related, but not identical, to understanding the process of aging. One idea from the field of aging that has gained considerable traction in the area of life histories is that life-history trade-offs may be mediated by free radical production and oxidative stress. We outline here developments in this field and summarize a number of important unresolved issues that may guide future research efforts. The issues are as follows. First, different tissues and macromolecular targets of oxidative stress respond differently during reproduction. The functional significance of these changes, however, remains uncertain. Consequently there is a need for studies that link oxidative stress measurements to functional outcomes, such as survival. Second, measurements of oxidative stress are often highly invasive or terminal. Terminal studies of oxidative stress in wild animals, where detailed life-history information is available, cannot generally be performed without compromising the aims of the studies that generated the life-history data. There is a need therefore for novel non-invasive measurements of multi-tissue oxidative stress. Third, laboratory studies provide unrivaled opportunities for experimental manipulation but may fail to expose the physiology underpinning life-history effects, because of the benign laboratory environment. Fourth, the idea that oxidative stress might underlie life-history trade-offs does not make specific enough predictions that are amenable to testing. Moreover, there is a paucity of good alternative theoretical models on which contrasting

The enactment stage of end-of-life decision-making for children.

Science.gov (United States)

Sullivan, Jane Elizabeth; Gillam, Lynn Heather; Monagle, Paul Terence

2018-01-11

Typically pediatric end-of-life decision-making studies have examined the decision-making process, factors, and doctors' and parents' roles. Less attention has focussed on what happens after an end-of-life decision is made; that is, decision enactment and its outcome. This study explored the views and experiences of bereaved parents in end-of-life decision-making for their child. Findings reported relate to parents' experiences of acting on their decision. It is argued that this is one significant stage of the decision-making process. A qualitative methodology was used. Semi-structured interviews were conducted with bereaved parents, who had discussed end-of-life decisions for their child who had a life-limiting condition and who had died. Data were thematically analysed. Twenty-five bereaved parents participated. Findings indicate that, despite differences in context, including the child's condition and age, end-of-life decision-making did not end when an end-of-life decision was made. Enacting the decision was the next stage in a process. Time intervals between stages and enactment pathways varied, but the enactment was always distinguishable as a separate stage. Decision enactment involved making further decisions - parents needed to discern the appropriate time to implement their decision to withdraw or withhold life-sustaining medical treatment. Unexpected events, including other people's actions, impacted on parents enacting their decision in the way they had planned. Several parents had to re-implement decisions when their child recovered from serious health issues without medical intervention. Significance of results A novel, critical finding was that parents experienced end-of-life decision-making as a sequence of interconnected stages, the final stage being enactment. The enactment stage involved further decision-making. End-of-life decision-making is better understood as a process rather than a discrete once-off event. The enactment stage has particular

Life history trade-offs imposed by dragline use in two money spiders.

Science.gov (United States)

Bonte, Dries; Verduyn, Lieselot; Braeckman, Bart P

2016-01-01

Trade-offs among life history traits are central to understanding the limits of adaptations to stress. In animals, virtually all decisions taken during life are expected to have downstream consequences. To what degree rare, but energy-demanding, decisions carry over to individual performance is rarely studied in arthropods. We used spiders as a model system to test how single investments in silk use - for dispersal or predator escape - affect individual performance. Silk produced for safe lines and as threads for ballooning is of the strongest kind and is energetically costly, especially when resources are limited. We induced dragline spinning in two species of money spider at similar quantities to that under natural conditions and tested trade-offs with lifespan and egg sac production under unlimited prey availability and a dietary restriction treatment. We demonstrate strong trade-offs between dragline spinning and survival and fecundity. Survival trade-offs were additive to those imposed by the dietary treatment, but a reduction in eggs produced after silk use was only prevalent under conditions where food was restricted during the spider's life. Because draglines are not recycled after their use for dispersal or predator escape, their spinning incurs substantial fitness costs in dispersal, especially in environments with prey limitation. Rare but energetically costly decisions related to dispersal or predator escape may thus carry over to adult performance and explain phenotypic heterogeneity in natural populations. © 2016. Published by The Company of Biologists Ltd.

The effect of life expectancy on aggression and generativity: a life history perspective.

Science.gov (United States)

Dunkel, Curtis S; Mathes, Eugene; Papini, Dennis R

2010-09-23

Following a model that is inclusive of both dispositional and situational influences on life-history behaviors and attitudes, the effect of life expectancies on aggression and generativity was examined. Consistent with the hypotheses it was found that shorter life expectancies led to an increase in the desire to aggress and a decrease in the desire to engage in generative behaviors. The results are discussed in terms of how life history theory can be used to frame research on person-situation interactions.

Implications of life-history strategies for obesity.

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Maner, Jon K; Dittmann, Andrea; Meltzer, Andrea L; McNulty, James K

2017-08-08

The association between low socioeconomic status (SES) and obesity is well documented. In the current research, a life history theory (LHT) framework provided an explanation for this association. Derived from evolutionary behavioral science, LHT emphasizes how variability in exposure to unpredictability during childhood gives rise to individual differences in a range of social psychological processes across the life course. Consistent with previous LHT research, the current findings suggest that exposure to unpredictability during childhood (a characteristic common to low SES environments) is associated with the adoption of a fast life-history strategy, one marked by impulsivity and a focus on short-term goals. We demonstrate that a fast life-history strategy, in turn, was associated with dysregulated weight-management behaviors (i.e., eating even in the absence of hunger), which were predictive of having a high body mass index (BMI) and being obese. In both studies, findings held while controlling for participants' current socioeconomic status, suggesting that obesity is rooted in childhood experiences. A serial mediation model in study 2 confirmed that effects of childhood SES on adult BMI and obesity can be explained in part by exposure to unpredictability, the adoption of a fast life-history strategy, and dysregulated-eating behaviors. These findings suggest that weight problems in adulthood may be rooted partially in early childhood exposure to unpredictable events and environments. LHT provides a valuable explanatory framework for understanding the root causes of obesity.

Human evolution, life history theory, and the end of biological reproduction.

Science.gov (United States)

Last, Cadell

2014-01-01

Throughout primate history there have been three major life history transitions towards increasingly delayed sexual maturation and biological reproduction, as well as towards extended life expectancy. Monkeys reproduce later and live longer than do prosimians, apes reproduce later and live longer than do monkeys, and humans reproduce later and live longer than do apes. These life history transitions are connected to increased encephalization. During the last life history transition from apes to humans, increased encephalization co-evolved with increased dependence on cultural knowledge for energy acquisition. This led to a dramatic pressure for more energy investment in growth over current biological reproduction. Since the industrial revolution socioeconomic development has led to even more energy being devoted to growth over current biological reproduction. I propose that this is the beginning of an ongoing fourth major primate life history transition towards completely delayed biological reproduction and an extension of the evolved human life expectancy. I argue that the only fundamental difference between this primate life history transition and previous life history transitions is that this transition is being driven solely by cultural evolution, which may suggest some deeper evolutionary transition away from biological evolution is already in the process of occurring.

End-of-Life Decisions and Advanced Old Age

Directory of Open Access Journals (Sweden)

Stoyles

2014-07-01

Full Text Available Despite the fact that most people die in advanced old age, little attention is given to cases involving older people in debates about the moral and legal dimensions of end-of-life decision making. The purpose of this paper is to establish some of the ways our discussions should change as we pay attention to important factors influencing end-of-life decisions for people in advanced old age. Focusing on the prevalence of comorbidities and the likelihood that people in advanced old age will experience an extended period of declining function before death, I argue that our debates should be expanded to include greater consideration of how we want to live in the final stages of life. With this, I am arguing against the tendency to think that “end-of-life” decision making concerns only making decisions about when and how it is appropriate to terminate a person’s life. I argue, further, that we should move away from the medicalization of dying.

The Dark Triad Traits from a Life History Perspective in Six Countries

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Peter K. Jonason

2017-08-01

Full Text Available Work on the Dark Triad traits has benefited from the use of a life history framework but it has been limited to primarily Western samples and indirect assessments of life history strategies. Here, we examine how the Dark Triad traits (i.e., psychopathy, Machiavellianism, and narcissism relate to two measures of individual differences in life history strategies. In Study 1 (N = 937, we replicated prior observed links between life history strategies, as measured by the Mini-K, and the Dark Triad traits using samples recruited from three countries. In Study 2 (N = 1032, we measured life history strategies using the Consideration of Future Consequences Scale and correlated it with the Dark Triad traits in samples recruited from three additional countries. While there was some variability across participants’ sex and country, the results were generally consistent in that psychopathy and (to a lesser extent Machiavellianism were related to faster life history strategies and narcissism was related to slower life history strategies. These results add cross-cultural data and the use of two measures of life history speed to understand the Dark Triad traits from a life history perspective.

Competence and Quality in Real-Life Decision Making

OpenAIRE

Geisler, Martin; Allwood, Carl Martin

2015-01-01

What distinguishes a competent decision maker and how should the issue of decision quality be approached in a real-life context? These questions were explored in three studies. In Study 1, using a web-based questionnaire and targeting a community sample, we investigated the relationships between objective and subjective indicators of real-life decision-making success. In Study 2 and 3, targeting two different samples of professionals, we explored if the prevalent cognitively oriented definiti...

Life History and Identity

Science.gov (United States)

Tierney, William G.

2013-01-01

This article uses the life history method to chronicle the challenges of a low-income, first-generation student en route to college. The paper addresses three questions: how Manuel navigates college and related topics such as roommates, family, and money; how he creates social networks; and how he works with adults such as teachers and…

Risk taking and adult attention deficit/hyperactivity disorder: A gap between real life behavior and experimental decision making.

Science.gov (United States)

Pollak, Yehuda; Shalit, Reut; Aran, Adi

2018-01-01

Adults with attention deficit/hyperactivity disorder (ADHD) are prone to suboptimal decision making and risk taking. The aim of this study was to test performance on a theoretically-based probabilistic decision making task in well-characterized adults with and without ADHD, and examine the relation between experimental risk taking and history of real-life risk-taking behavior, defined as cigarette, alcohol, and street drug use. University students with and without ADHD completed a modified version of the Cambridge Gambling Test, in which they had to choose between alternatives varied by level of risk, and reported their history of substance use. Both groups showed similar patterns of risk taking on the experimental decision making task, suggesting that ADHD is not linked to low sensitivity to risk. Past and present substance use was more prevalent in adults with ADHD. These finding question the validity of experimental probabilistic decision making task as a valid model for ADHD-related risk-taking behavior. Copyright © 2017 Elsevier B.V. All rights reserved.

History dependence in insect flight decisions during odor tracking.

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Pang, Rich; van Breugel, Floris; Dickinson, Michael; Riffell, Jeffrey A; Fairhall, Adrienne

2018-02-01

Natural decision-making often involves extended decision sequences in response to variable stimuli with complex structure. As an example, many animals follow odor plumes to locate food sources or mates, but turbulence breaks up the advected odor signal into intermittent filaments and puffs. This scenario provides an opportunity to ask how animals use sparse, instantaneous, and stochastic signal encounters to generate goal-oriented behavioral sequences. Here we examined the trajectories of flying fruit flies (Drosophila melanogaster) and mosquitoes (Aedes aegypti) navigating in controlled plumes of attractive odorants. While it is known that mean odor-triggered flight responses are dominated by upwind turns, individual responses are highly variable. We asked whether deviations from mean responses depended on specific features of odor encounters, and found that odor-triggered turns were slightly but significantly modulated by two features of odor encounters. First, encounters with higher concentrations triggered stronger upwind turns. Second, encounters occurring later in a sequence triggered weaker upwind turns. To contextualize the latter history dependence theoretically, we examined trajectories simulated from three normative tracking strategies. We found that neither a purely reactive strategy nor a strategy in which the tracker learned the plume centerline over time captured the observed history dependence. In contrast, "infotaxis", in which flight decisions maximized expected information gain about source location, exhibited a history dependence aligned in sign with the data, though much larger in magnitude. These findings suggest that while true plume tracking is dominated by a reactive odor response it might also involve a history-dependent modulation of responses consistent with the accumulation of information about a source over multi-encounter timescales. This suggests that short-term memory processes modulating decision sequences may play a role in

Deferred Personal Life Decisions of Women Physicians.

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Bering, Jamie; Pflibsen, Lacey; Eno, Cassie; Radhakrishnan, Priya

2018-05-01

Inadequate work-life balance can have significant implications regarding individual performance, retention, and on the future of the workforce in medicine. The purpose of this study was to determine whether women physicians defer personal life decisions in pursuit of their medical career. We conducted a survey study of women physicians ages 20-80 from various medical specialties using a combination of social media platforms and women physicians' professional listservs with 801 survey responses collected from May through November 2015. The primary endpoint was whether women physicians deferred personal life decisions in pursuit of their medical career. Secondary outcomes include types of decisions deferred and correlations with age, hours worked per week, specialty, number of children, and career satisfaction. Respondents were categorized into deferred and nondeferred groups. Personal decision deferments were reported by 64% of respondents. Of these, 86% reported waiting to have children and 22% reported waiting to get married. Finally, while 85% of women in the nondeferment group would choose medicine again as a career, only 71% of women in the deferment group would do so (p job satisfaction, and insurance/administrative burden. The results of this survey have significant implications on the future of the workforce in medicine. Overall, our analysis shows that 64% of women physicians defer important life decisions in pursuit of their medical career. With an increase in the number of women physicians entering the workforce, lack of support and deferred personal decisions have a potential negative impact on individual performance and retention. Employers must consider the economic impact and potential workforce shortages that may develop if these issues are not addressed.

What influences parents' decisions to limit or withdraw life support?

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Sharman, Mahesh; Meert, Kathleen L; Sarnaik, Ashok P

2005-09-01

Decisions to forgo life support from critically ill children are commonly faced by parents and physicians. Previous research regarding parents' perspectives on the decision-making process has been limited by retrospective methods and the use of closed-ended questionnaires. We prospectively identified and described parents' self-reported influences on decisions to forgo life support from their children. Deeper understanding of parents' views will allow physicians to focus end-of-life discussions on factors important to parents and help resolve conflicts. Prospective, qualitative pilot study. Pediatric intensive care unit of a university-affiliated children's hospital. A total of 14 parents of ten children whose pediatric intensive care unit physician had made a recommendation to limit or withdraw life support. : In-depth, semistructured interviews were conducted with parents during their decision-making process. Factors influencing the parents in this study in their decision to forgo life support included their previous experience with death and end-of-life decision making for others, their personal observations of their child's suffering, their perceptions of their child's will to survive, their need to protect and advocate for their child, and the family's financial resources and concerns regarding life-long care. Parents in this study expressed the desire to do what is best for their child but struggled with feelings of selfishness, guilt, and the need to avoid agony and sorrow. Physician recommendations, review of options, and joint formulation of a plan helped parents gain a sense of control over their situation. Parents of eight children agreed to forgo life support and parents of two did not. Prospective interviews with open-ended questions identified factors influencing parents' decision making not previously described in the critical care literature such as parents' past experiences with end-of-life decisions and their anticipated emotional adjustments and

The Tsimane Health and Life History Project: Integrating anthropology and biomedicine.

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Gurven, Michael; Stieglitz, Jonathan; Trumble, Benjamin; Blackwell, Aaron D; Beheim, Bret; Davis, Helen; Hooper, Paul; Kaplan, Hillard

2017-04-01

The Tsimane Health and Life History Project, an integrated bio-behavioral study of the human life course, is designed to test competing hypotheses of human life-history evolution. One aim is to understand the bidirectional connections between life history and social behavior in a high-fertility, kin-based context lacking amenities of modern urban life (e.g. sanitation, banks, electricity). Another aim is to understand how a high pathogen burden influences health and well-being during development and adulthood. A third aim addresses how modernization shapes human life histories and sociality. Here we outline the project's goals, history, and main findings since its inception in 2002. We reflect on the implications of current findings and highlight the need for more coordinated ethnographic and biomedical study of contemporary nonindustrial populations to address broad questions that can situate evolutionary anthropology in a key position within the social and life sciences. © 2017 The Authors Evolutionary Anthropology: Issues, News, and Reviews Published by Wiley Periodicals, Inc.

Development of a diagnostic decision tree for obstructive pulmonary diseases based on real-life data

Directory of Open Access Journals (Sweden)

Esther I. Metting

2016-01-01

Full Text Available The aim of this study was to develop and explore the diagnostic accuracy of a decision tree derived from a large real-life primary care population. Data from 9297 primary care patients (45% male, mean age 53±17 years with suspicion of an obstructive pulmonary disease was derived from an asthma/chronic obstructive pulmonary disease (COPD service where patients were assessed using spirometry, the Asthma Control Questionnaire, the Clinical COPD Questionnaire, history data and medication use. All patients were diagnosed through the Internet by a pulmonologist. The Chi-squared Automatic Interaction Detection method was used to build the decision tree. The tree was externally validated in another real-life primary care population (n=3215. Our tree correctly diagnosed 79% of the asthma patients, 85% of the COPD patients and 32% of the asthma–COPD overlap syndrome (ACOS patients. External validation showed a comparable pattern (correct: asthma 78%, COPD 83%, ACOS 24%. Our decision tree is considered to be promising because it was based on real-life primary care patients with a specialist's diagnosis. In most patients the diagnosis could be correctly predicted. Predicting ACOS, however, remained a challenge. The total decision tree can be implemented in computer-assisted diagnostic systems for individual patients. A simplified version of this tree can be used in daily clinical practice as a desk tool.

Development of a diagnostic decision tree for obstructive pulmonary diseases based on real-life data

Science.gov (United States)

in ’t Veen, Johannes C.C.M.; Dekhuijzen, P.N. Richard; van Heijst, Ellen; Kocks, Janwillem W.H.; Muilwijk-Kroes, Jacqueline B.; Chavannes, Niels H.; van der Molen, Thys

2016-01-01

The aim of this study was to develop and explore the diagnostic accuracy of a decision tree derived from a large real-life primary care population. Data from 9297 primary care patients (45% male, mean age 53±17 years) with suspicion of an obstructive pulmonary disease was derived from an asthma/chronic obstructive pulmonary disease (COPD) service where patients were assessed using spirometry, the Asthma Control Questionnaire, the Clinical COPD Questionnaire, history data and medication use. All patients were diagnosed through the Internet by a pulmonologist. The Chi-squared Automatic Interaction Detection method was used to build the decision tree. The tree was externally validated in another real-life primary care population (n=3215). Our tree correctly diagnosed 79% of the asthma patients, 85% of the COPD patients and 32% of the asthma–COPD overlap syndrome (ACOS) patients. External validation showed a comparable pattern (correct: asthma 78%, COPD 83%, ACOS 24%). Our decision tree is considered to be promising because it was based on real-life primary care patients with a specialist's diagnosis. In most patients the diagnosis could be correctly predicted. Predicting ACOS, however, remained a challenge. The total decision tree can be implemented in computer-assisted diagnostic systems for individual patients. A simplified version of this tree can be used in daily clinical practice as a desk tool. PMID:27730177

Evolution, human-microbe interactions, and life history plasticity.

Science.gov (United States)

Rook, Graham; Bäckhed, Fredrik; Levin, Bruce R; McFall-Ngai, Margaret J; McLean, Angela R

2017-07-29

A bacterium was once a component of the ancestor of all eukaryotic cells, and much of the human genome originated in microorganisms. Today, all vertebrates harbour large communities of microorganisms (microbiota), particularly in the gut, and at least 20% of the small molecules in human blood are products of the microbiota. Changing human lifestyles and medical practices are disturbing the content and diversity of the microbiota, while simultaneously reducing our exposures to the so-called old infections and to organisms from the natural environment with which human beings co-evolved. Meanwhile, population growth is increasing the exposure of human beings to novel pathogens, particularly the crowd infections that were not part of our evolutionary history. Thus some microbes have co-evolved with human beings and play crucial roles in our physiology and metabolism, whereas others are entirely intrusive. Human metabolism is therefore a tug-of-war between managing beneficial microbes, excluding detrimental ones, and channelling as much energy as is available into other essential functions (eg, growth, maintenance, reproduction). This tug-of-war shapes the passage of each individual through life history decision nodes (eg, how fast to grow, when to mature, and how long to live). Copyright © 2017 Elsevier Ltd. All rights reserved.

End-of-life decision making in the ICU.

Science.gov (United States)

Siegel, Mark D

2009-03-01

A large proportion of deaths, particularly in the developed world, follows admission to an ICU. Therefore, end-of life decision making is an essential facet of critical care practice. For intensivists, managing death in the critically ill has become a key professional skill. They must be thoroughly familiar with the ethical framework that guides end-of-life decision making. Decisions should generally be made collaboratively by clinicians partnering with patients' families. Treatment choices should be crafted to meet specific, achievable goals. A rational, empathic approach to working with families should encourage appropriate, mutually satisfactory outcomes.

Life history theory and breast cancer risk: methodological and theoretical challenges: Response to "Is estrogen receptor negative breast cancer risk associated with a fast life history strategy?".

Science.gov (United States)

Aktipis, Athena

2016-01-01

In a meta-analysis published by myself and co-authors, we report differences in the life history risk factors for estrogen receptor negative (ER-) and estrogen receptor positive (ER+) breast cancers. Our meta-analysis did not find the association of ER- breast cancer risk with fast life history characteristics that Hidaka and Boddy suggest in their response to our article. There are a number of possible explanations for the differences between their conclusions and the conclusions we drew from our meta-analysis, including limitations of our meta-analysis and methodological challenges in measuring and categorizing estrogen receptor status. These challenges, along with the association of ER+ breast cancer with slow life history characteristics, may make it challenging to find a clear signal of ER- breast cancer with fast life history characteristics, even if that relationship does exist. The contradictory results regarding breast cancer risk and life history characteristics illustrate a more general challenge in evolutionary medicine: often different sub-theories in evolutionary biology make contradictory predictions about disease risk. In this case, life history models predict that breast cancer risk should increase with faster life history characteristics, while the evolutionary mismatch hypothesis predicts that breast cancer risk should increase with delayed reproduction. Whether life history tradeoffs contribute to ER- breast cancer is still an open question, but current models and several lines of evidence suggest that it is a possibility. © The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

Exploring Teachers' Curriculum Decision Making: Insights from History Education

Science.gov (United States)

Harris, Richard; Reynolds, Rosemary

2018-01-01

This paper explores teachers' decision making by examining the topics that 11 history teachers from 10 schools in England chose to teach and how they approached teaching these topics. Data were gathered from curriculum documents and semi-structured interviews in which teachers' topic choices and approaches to history were explored. Most teachers…

Interrupting Life History: The Evolution of Relationship within Research

Science.gov (United States)

Hallett, Ronald E.

2013-01-01

In this paper the author explores how relationships are defined within the context of constructing a life history. The life history of Benjamin, a homeless young man transitioning to adulthood, is used to illustrate how difficult it is to define the parameters of the research environment. During an "ethically important moment" in the…

Life history of the Harlequin ladybird, Harmonia axyridis; a global meta-analysis

NARCIS (Netherlands)

Raak-van den Berg, C.L.; Hemerik, A.; Werf, van der W.; Jong, de P.W.; Lenteren, van J.C.

2017-01-01

Data collected en used for a meta analysis on life history data of H. axyridis. And the resulting 20 best models for each life history characteristic. Published in the paper: Life history of the Harlequin ladybird, Harmonia axyridis; a global meta-analysis.

The life trajectories modality of oral history

Directory of Open Access Journals (Sweden)

Rita de Cássia Gonçalves

2007-05-01

Full Text Available This article seeks to explore the potential of qualitative research. It presents the life trajectory modality of the oral history method, to discuss the possibility of its utilization in scientific research in the Social Work profession. The epistemological foundations of oral history are discussed to establish its scientific character. The life trajectories modality is presented as a historic and social construction that utilizes different interview techniques to give voice to previously invisible subjects, indicating the principal phases of the methodological procedures used in this approach. The conclusions highlight the importance of the construction of this model and its projection as a research proposal that implies a process of understanding and analyzing the social universes that are contextualized and interconnected, considering the realities of the life trajectories of the subjects studied.

A brief history of decision making.

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Buchanan, Leigh; O'Connell, Andrew

2006-01-01

Sometime around the middle of the past century, telephone executive Chester Barnard imported the term decision making from public administration into the business world. There it began to replace narrower terms, like "resource allocation" and "policy making," shifting the way managers thought about their role from continuous, Hamlet-like deliberation toward a crisp series of conclusions reached and actions taken. Yet, decision making is, of course, a broad and ancient human pursuit, flowing back to a time when people sought guidance from the stars. From those earliest days, we have strived to invent better tools for the purpose, from the Hindu-Arabic systems for numbering and algebra, to Aristotle's systematic empiricism, to friar Occam's advances in logic, to Francis Bacon's inductive reasoning, to Descartes's application of the scientific method. A growing sophistication with managing risk, along with a nuanced understanding of human behavior and advances in technology that support and mimic cognitive processes, has improved decision making in many situations. Even so, the history of decision-making strategies--captured in this time line and examined in the four accompanying essays on risk, group dynamics, technology, and instinct--has not marched steadily toward perfect rationalism. Twentieth-century theorists showed that the costs of acquiring information lead executives to make do with only good-enough decisions. Worse, people decide against their own economic interests even when they know better. And in the absence of emotion, it's impossible to make any decisions at all. Erroneous framing, bounded awareness, excessive optimism: The debunking of Descartes's rational man threatens to swamp our confidence in our choices. Is it really surprising, then, that even as technology dramatically increases our access to information, Malcolm Gladwell extols the virtues of gut decisions made, literally, in the blink of an eye?

Variation in adult life history and stress resistance across five ...

Indian Academy of Sciences (India)

Unknown

Life-history evolution in Drosophila has been extensively studied, and .... Overall, if one looks at studies of adult life history and ...... Thus, if the balance of biotic and abiotic selective ... these four species, and indicate that more detailed work on.

Frustration influences impact of history and disciplinary attitudes on physical discipline decision making.

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Russa, Mary B; Rodriguez, Christina M; Silvia, Paul J

2014-01-01

Although intergenerational patterns of punitive physical punishment garner considerable research attention, the mechanisms by which historical, cognitive, and contextual factors interplay to influence disciplinary responding remains poorly understood. Disciplinary attitudes have been shown to mediate the association between disciplinary history and disciplinary responding. The present study investigated whether frustration influences these mediation effects. Half of a sample of 330 undergraduates was randomly assigned to frustration induction. Structural equation modeling confirmed that, for participants in the frustration condition, the relation between disciplinary history and physical discipline decision-making was fully mediated by attitudes approving physical discipline. In contrast, for respondents in the no-frustration condition, the pathway from disciplinary history to discipline decision-making was only partially mediated by attitudes. Under conditions of frustration, attitudes may become a more central means by which personal disciplinary history is associated with disciplinary decision-making. © 2013 Wiley Periodicals, Inc.

Late-life and life history predictors of older adults' high-risk alcohol consumption and drinking problems.

Science.gov (United States)

Moos, Rudolf H; Schutte, Kathleen K; Brennan, Penny L; Moos, Bernice S

2010-04-01

This prospective, longitudinal study focused on late-life and life history predictors of high-risk alcohol consumption and drinking problems during a 20-year interval as adults matured from age 55-65 to 75-85. A sample of older community residents (N=719) who had consumed alcohol in the past year or shortly before was surveyed at baseline and 10 and 20 years later. At each contact point, participants completed an inventory that assessed their alcohol consumption, drinking problems, and personal and life context factors. Participants also provided information about their life history of drinking and help-seeking. Older adults who, at baseline, had more friends who approved of drinking, relied on substances for tension reduction, and had more financial resources were more likely to engage in high-risk alcohol consumption and to incur drinking problems at 10- and 20-year follow-ups. With respect to life history factors, drinking problems by age 50 were associated with a higher likelihood of late-life high-risk alcohol consumption and drinking problems; having tried to cut down on drinking and participation in Alcoholics Anonymous were associated with a lower likelihood of high-risk consumption and problems. Specific late-life and life history factors can identify older adults likely to engage in excessive alcohol consumption 10 and 20 years later. Targeted screening that considers current alcohol consumption and life context, and history of drinking problems and help-seeking, could help identify older adults at higher risk for excessive or problematic drinking. Published by Elsevier Ireland Ltd.

The life-history basis of behavioural innovations.

Science.gov (United States)

Sol, Daniel; Sayol, Ferran; Ducatez, Simon; Lefebvre, Louis

2016-03-19

The evolutionary origin of innovativeness remains puzzling because innovating means responding to novel or unusual problems and hence is unlikely to be selected by itself. A plausible alternative is considering innovativeness as a co-opted product of traits that have evolved for other functions yet together predispose individuals to solve problems by adopting novel behaviours. However, this raises the question of why these adaptations should evolve together in an animal. Here, we develop the argument that the adaptations enabling animals to innovate evolve together because they are jointly part of a life-history strategy for coping with environmental changes. In support of this claim, we present comparative evidence showing that in birds, (i) innovative propensity is linked to life histories that prioritize future over current reproduction, (ii) the link is in part explained by differences in brain size, and (iii) innovative propensity and life-history traits may evolve together in generalist species that frequently expose themselves to novel or unusual conditions. Combined with previous evidence, these findings suggest that innovativeness is not a specialized adaptation but more likely part of a broader general adaptive system to cope with changes in the environment. © 2016 The Author(s).

Timing of seasonal migration in mule deer: effects of climate, plant phenology, and life-history characteristics

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Monteith, Kevin L.; Bleich, Vernon C.; Stephenson, Thomas R.; Pierce, Beck M.; Conner, Mary M.; Klaver, Robert W.; Bowyer, R. Terry

2011-01-01

Phenological events of plants and animals are sensitive to climatic processes. Migration is a life-history event exhibited by most large herbivores living in seasonal environments, and is thought to occur in response to dynamics of forage and weather. Decisions regarding when to migrate, however, may be affected by differences in life-history characteristics of individuals. Long-term and intensive study of a population of mule deer (Odocoileus hemionus) in the Sierra Nevada, California, USA, allowed us to document patterns of migration during 11 years that encompassed a wide array of environmental conditions. We used two new techniques to properly account for interval-censored data and disentangle effects of broad-scale climate, local weather patterns, and plant phenology on seasonal patterns of migration, while incorporating effects of individual life-history characteristics. Timing of autumn migration varied substantially among individual deer, but was associated with the severity of winter weather, and in particular, snow depth and cold temperatures. Migratory responses to winter weather, however, were affected by age, nutritional condition, and summer residency of individual females. Old females and those in good nutritional condition risked encountering severe weather by delaying autumn migration, and were thus risk-prone with respect to the potential loss of foraging opportunities in deep snow compared with young females and those in poor nutritional condition. Females that summered on the west side of the crest of the Sierra Nevada delayed autumn migration relative to east-side females, which supports the influence of the local environment on timing of migration. In contrast, timing of spring migration was unrelated to individual life-history characteristics, was nearly twice as synchronous as autumn migration, differed among years, was related to the southern oscillation index, and was influenced by absolute snow depth and advancing phenology of plants

Bluefin Tuna Life History (1972-1979)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Catch and size data for animals from which a collection of fish parts were done for life history studies. These samples will be used in comparison studies with more...

Life history theory predicts fish assemblage response to hydrologic regimes.

Science.gov (United States)

Mims, Meryl C; Olden, Julian D

2012-01-01

The hydrologic regime is regarded as the primary driver of freshwater ecosystems, structuring the physical habitat template, providing connectivity, framing biotic interactions, and ultimately selecting for specific life histories of aquatic organisms. In the present study, we tested ecological theory predicting directional relationships between major dimensions of the flow regime and life history composition of fish assemblages in perennial free-flowing rivers throughout the continental United States. Using long-term discharge records and fish trait and survey data for 109 stream locations, we found that 11 out of 18 relationships (61%) tested between the three life history strategies (opportunistic, periodic, and equilibrium) and six hydrologic metrics (two each describing flow variability, predictability, and seasonality) were statistically significant (P history strategies, with 82% of all significant relationships observed supporting predictions from life history theory. Specifically, we found that (1) opportunistic strategists were positively related to measures of flow variability and negatively related to predictability and seasonality, (2) periodic strategists were positively related to high flow seasonality and negatively related to variability, and (3) the equilibrium strategists were negatively related to flow variability and positively related to predictability. Our study provides important empirical evidence illustrating the value of using life history theory to understand both the patterns and processes by which fish assemblage structure is shaped by adaptation to natural regimes of variability, predictability, and seasonality of critical flow events over broad biogeographic scales.

Issues surrounding end-of-life decision-making

Directory of Open Access Journals (Sweden)

Tejwani V

2013-08-01

Full Text Available Vickram Tejwani,1,* YiFan Wu,1,* Sabrina Serrano,2 Luis Segura,2 Michael Bannon,3 Qi Qian1 1Department of Medicine, Division of Nephrology and Hypertension, 2Mayo Graduate School, 3Department of Trauma, Critical Care, and General Surgery, Mayo Clinic College of Medicine, Rochester, MN, USA *These authors contributed equally to this work Abstract: End-of-life decision-making is a complex process that can be extremely challenging. We describe a 42-year-old woman in an irreversible coma without an advance directive. The case serves to illustrate the complications that can occur in end-of-life decision-making and challenges in resolving difficult futility disputes. We review the role of advance directives in planning end-of-life care, the responsibility and historical performance of patient surrogates, the genesis of futility disputes, and approaches to resolving disputes. Keywords: end-of-life care, advance directive, surrogate, futility dispute, conflict resolution

Inadvertent Exemplars: Life History Portraits of Two Socially Just Principals

Science.gov (United States)

Scanlan, Martin

2012-01-01

This study creates life history portraits of two White middle-class native-English-speaking principals demonstrating commitments to social justice in their work in public elementary schools serving disproportionately high populations of students who are marginalized by poverty, race, and linguistic heritage. Through self-reported life histories of…

To Fairly Tell: Social Mobility, Life Histories, and the Anthropologist

Science.gov (United States)

Benei, Veronique

2010-01-01

This article focuses on social agents' own understandings of socio-economic mobility and social achievement, exploring the possibilities offered by the tool of "family" life history in the context of formerly Untouchable communities in western India, Maharashtra. While arguing in favour of family life histories as both resource and…

Life-oriented approach for urban policy decision-making: Surveys and applications

OpenAIRE

Junyi Zhang; Yubing Xiong; Minh Tu Tran

2014-01-01

In this study, we propose an additional approach, called life-oriented approach, for supporting urban policy decisions. The life-oriented approach argues that people's decisions on various life choices are not independent of each other and that an understanding of life choices should not be constrained by the boundary of any single discipline. People's life choices are closely linked with the quality of life (QOL), which can be roughly captured from the perspective of life domains such as res...

Scaffolding across the lifespan in history-dependent decision-making.

Science.gov (United States)

Cooper, Jessica A; Worthy, Darrell A; Gorlick, Marissa A; Maddox, W Todd

2013-06-01

We examined the relationship between pressure and age-related changes in decision-making using a task for which currently available rewards depend on the participant's previous history of choices. Optimal responding in this task requires the participant to learn how his or her current choices affect changes in the future rewards given for each option. Building on the scaffolding theory of aging and cognition, we predicted that when additional frontal resources are available, compensatory recruitment leads to increased monitoring and increased use of heuristic-based strategies, ultimately leading to better performance. Specifically, we predicted that scaffolding would result in an age-related performance advantage under no pressure conditions. We also predicted that, although younger adults would engage in scaffolding under pressure, older adults would not have additional resources available for increased scaffolding under pressure-packed conditions, leading to an age-related performance deficit. Both predictions were supported by the data. In addition, computational models were used to evaluate decision-making strategies employed by each participant group. As expected, older adults under no pressure conditions and younger adults under pressure conditions showed increased use of heuristic-based strategies relative to older adults under pressure and younger adults under no pressure, respectively. These results are consistent with the notion that scaffolding can occur across the life span in the face of an environmental challenge. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Assessing the quality of life history information in publicly available databases.

Science.gov (United States)

Thorson, James T; Cope, Jason M; Patrick, Wesley S

2014-01-01

Single-species life history parameters are central to ecological research and management, including the fields of macro-ecology, fisheries science, and ecosystem modeling. However, there has been little independent evaluation of the precision and accuracy of the life history values in global and publicly available databases. We therefore develop a novel method based on a Bayesian errors-in-variables model that compares database entries with estimates from local experts, and we illustrate this process by assessing the accuracy and precision of entries in FishBase, one of the largest and oldest life history databases. This model distinguishes biases among seven life history parameters, two types of information available in FishBase (i.e., published values and those estimated from other parameters), and two taxa (i.e., bony and cartilaginous fishes) relative to values from regional experts in the United States, while accounting for additional variance caused by sex- and region-specific life history traits. For published values in FishBase, the model identifies a small positive bias in natural mortality and negative bias in maximum age, perhaps caused by unacknowledged mortality caused by fishing. For life history values calculated by FishBase, the model identified large and inconsistent biases. The model also demonstrates greatest precision for body size parameters, decreased precision for values derived from geographically distant populations, and greatest between-sex differences in age at maturity. We recommend that our bias and precision estimates be used in future errors-in-variables models as a prior on measurement errors. This approach is broadly applicable to global databases of life history traits and, if used, will encourage further development and improvements in these databases.

Life history strategy of the honey bee, Apis mellifera.

Science.gov (United States)

Seeley, Thomas D

1978-01-01

The feral honey bee queens (colonies) of central New York State (USA) show a K-type life history strategy. Their demographic characteristics include low early life mortality, low reproductive rate, long lifespan, high population stability and repeated reproductions. Identifying the life history strategy of these bees reveals the general pattern of selection for competitive ability, rather than productivity, which has shaped their societies. Selection for competitive power explains the adaptiveness (compared with alternatives found in many other insect societies) of the large perennial colonies, infrequent but expensive offspring, and efficient foraging which characterize the social organization of these bees.

Late-Life and Life History Predictors of Older Adults of High-Risk Alcohol Consumption and Drinking Problems

Science.gov (United States)

Moos, Rudolf H.; Schutte, Kathleen K.; Brennan, Penny L.; Moos, Bernice S.

2009-01-01

Aims This prospective, longitudinal study focused on late-life and life history predictors of high-risk alcohol consumption and drinking problems during a 20-year interval as adults matured from age 55–65 to age 75–85. Design, Setting, Participants A sample of older community residents (N=719) who had consumed alcohol in the past year or shortly before was surveyed at baseline and 10 years and 20 years later. Measurements At each contact point, participants completed an inventory that assessed their alcohol consumption, drinking problems, and personal and life context factors. Participants also provided information about their life history of drinking and help-seeking. Results Older adults who, at baseline, had more friends who approved of drinking, relied on substances for tension reduction, and had more financial resources were more likely to engage in high-risk alcohol consumption and to incur drinking problems at 10-year and 20-year follow-ups. With respect to life history factors, drinking problems by age 50 were associated with a higher likelihood of late-life high-risk alcohol consumption and drinking problems; having tried to cut down on drinking and participation in Alcoholics Anonymous were associated with a lower likelihood of high-risk consumption and problems. Conclusion Specific late-life and life history factors can identify older adults likely to engage in excessive alcohol consumption 10 and 20 years later. Targeted screening that considers current alcohol consumption and life context, and history of drinking problems and help-seeking, could help identify older adults at higher risk for excessive or problematic drinking. PMID:19969428

Our nuclear history

International Nuclear Information System (INIS)

Marx, G.

1986-01-01

The article on nuclear history is contained in a booklet on the Revised Nuffield Advanced Physics Course. The author shows how the difficult decisions about energy supplies at the end of the twentieth century can be seen as a consequence of the history and evolution of the Universe and of life, and mankind's activities on earth. The topics discussed include:-the origin of the Universe, formation of light elements, formation of carbon and oxygen, supernovae and nuclear equilibrium, formation of planets, development of life on earth, mankind and the use of fuels, and the nuclear valley. (UK)

Life history strategies of fish species and biodiversity in eastern USA streams

Science.gov (United States)

Meador, Michael R.; Brown, Larry M.

2015-01-01

Predictive models have been used to determine fish species that occur less frequently than expected (decreasers) and those that occur more frequently than expected (increasers) in streams in the eastern U.S. Coupling life history traits with 51 decreaser and 38 increaser fish species provided the opportunity to examine potential mechanisms associated with predicted changes in fish species distributions in eastern streams. We assigned six life history traits – fecundity, longevity, maturation age, maximum total length, parental care, and spawning season duration – to each fish species. Decreaser species were significantly smaller in size and shorter-lived with reduced fecundity and shorter spawning seasons compared to increaser species. Cluster analysis of traits revealed correspondence with a life history model defining equilibrium (low fecundity, high parental care), opportunistic (early maturation, low parental care), and periodic (late maturation, high fecundity, low parental care) end-point strategies. Nearly 50 % of decreaser species were associated with an intermediate opportunistic-periodic strategy, suggesting that abiotic factors such as habitat specialization and streamflow alteration may serve as important influences on life history traits and strategies of decreaser species. In contrast, the percent of increaser species among life history strategy groups ranged from 21 to 32 %, suggesting that life history strategies of increaser species were more diverse than those of decreaser species. This study highlights the utility of linking life history theory to biodiversity to better understand mechanisms that contribute to fish species distributions in the eastern U.S.

Using life-histories to predict and interpret variability in yolk hormones.

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Love, O P; Gilchrist, H G; Bêty, J; Wynne-Edwards, K E; Berzins, L; Williams, T D

2009-09-01

Variation in yolk hormones is assumed to provide the plasticity necessary for mothers to individually optimize reproductive decisions via changes in offspring phenotype, the benefit being to maximise fitness. However, rather than routinely expecting adaptive variation within all species, the pattern and magnitude of yolk hormone deposition should theoretically relate to variation in life-histories. Here we present data on intra-clutch variation in yolk corticosterone in three species along a developmental continuum (European starling (Sturnus vulgaris): fully altricial; black guillemot (Cepphus grylle): semi-precocial; common eider (Somateria mollissima): fully precocial) to examine how and why variation in life-histories might relate to the evolution of variation in yolk steroids. Starlings and guillemots showed a significant increase in yolk corticosterone across the laying sequence; however, we found no pattern within eider clutches. Moreover, starlings showed the largest difference (94.6%) in yolk corticosterone between first- and last-laid eggs, whereas guillemots showed a moderate difference (58.9%). Despite these general species-specific patterns, individuals showed marked variation in the intra-clutch patterns of yolk corticosterone within each species indicating potential differences in intra-clutch flexibility among females. It is well documented that exposure to elevated yolk glucocorticoids reduces offspring quality at birth/hatching in many taxa and it has therefore been proposed that elevated yolk levels may modulate offspring competition and/or facilitate brood reduction under harsh conditions in birds. Our data suggests that intra-clutch variation in yolk corticosterone has the potential to act as an adaptive maternal effect in species where modulation of competition between nest-bound offspring would benefit mothers (starlings and guillemots). However, in precocial species where mothers would not benefit from a modulation of offspring quality

Nuclear plant life - A business decision

International Nuclear Information System (INIS)

Joosten, J.K.

1995-01-01

Regarding the future of the nuclear power option, many scenarios have been put forth over the years. The most commonly accepted projections for installed nuclear capacity show it growing at a rate of about 2% per year throughout the next few decades. These projections appear modes on the surface. However, underlying the projections are critical assumptions and sometimes misconceptions about the lifetimes of existing reactors and how they are determined. The notion of a 40 year plant life is very common. Consequently, many projections start either with the assumption that no plants will be retired in the near terms or with the assumption that each retired plant will be replaced by another nuclear plant after 40 years. Effectively, these assumptions yield future projections for installed capacity that might be characterized as low growth, medium growth and high growth scenarios - or grow, grow, grow. The question remains as to whether or not these assumptions accurately model the driving forces and constraints to nuclear development. After all, there is no scientific basis for believing that all plants, PWRs BWRs, RBMKs, etc., should have the same 40 year life. Most power plant owners purchase the plant for the main reason of supplying electrical power to their consumer. For these owners, electricity production is a day to day commercial activity with various alternatives on how to achieve the prime objective. The decision of which electricity generation alternative to select (gas, coal, nuclear or renewable energy) and how long to operate the plant before replacing it with a new one is essentially a business decision. The paper discusses ageing, the nuclear plant life decision process, the factors which influence the decision and their ramifications regarding the near term growth of nuclear power capacity. The modelling of nuclear plant lifetimes is also discussed. (author). 5 refs, 10 figs, 1 tab

The Digital Life History Project: Intergenerational Collaborative Research

Science.gov (United States)

Loe, Meika

2013-01-01

This article describes the Digital Life History Project, a 10-week "lab" linked to a course on aging, in which students and community-dwelling elders work together to create a short digital story honoring the elder's life. After two interview sessions, the pair works together to produce a 3- to 5-minute digital life story narrated by the elder.…

Fast-slow continuum and reproductive strategies structure plant life-history variation worldwide

DEFF Research Database (Denmark)

Salguero-Gómez, Roberto; Jones, Owen R; Jongejans, Eelke

2016-01-01

The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous...... variation in life history are poorly understood. We use demographic data from 418 plant species in the wild, from annual herbs to supercentennial trees, to examine how growth form, habitat, and phylogenetic relationships structure plant life histories and to develop a framework to predict population...

Adaptable history biases in human perceptual decisions.

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Abrahamyan, Arman; Silva, Laura Luz; Dakin, Steven C; Carandini, Matteo; Gardner, Justin L

2016-06-21

When making choices under conditions of perceptual uncertainty, past experience can play a vital role. However, it can also lead to biases that worsen decisions. Consistent with previous observations, we found that human choices are influenced by the success or failure of past choices even in a standard two-alternative detection task, where choice history is irrelevant. The typical bias was one that made the subject switch choices after a failure. These choice history biases led to poorer performance and were similar for observers in different countries. They were well captured by a simple logistic regression model that had been previously applied to describe psychophysical performance in mice. Such irrational biases seem at odds with the principles of reinforcement learning, which would predict exquisite adaptability to choice history. We therefore asked whether subjects could adapt their irrational biases following changes in trial order statistics. Adaptability was strong in the direction that confirmed a subject's default biases, but weaker in the opposite direction, so that existing biases could not be eradicated. We conclude that humans can adapt choice history biases, but cannot easily overcome existing biases even if irrational in the current context: adaptation is more sensitive to confirmatory than contradictory statistics.

Revolutionaries, wanderers, converts, and compliants: Life histories of extreme right activists

NARCIS (Netherlands)

Linden, A.; Klandermans, P.G.

2007-01-01

Life-history interviews were conducted with thirty-six extreme right activists in the Netherlands (1996-1998). Becoming an activist was a matter of continuity, of conversion, or of compliance. Continuity denotes life histories wherein movement membership and participation are a natural consequence

Explaining density-dependent regulation in earthworm populations using life-history analysis

NARCIS (Netherlands)

Kammenga, J.E.; Spurgeon, D.J.; Svendsen, C.; Weeks, J.M.

2003-01-01

At present there is little knowledge about how density regulates population growth rate and to what extent this is determined by life-history patterns. We compared density dependent population consequences in the Nicholsonian sense based oil experimental observations and life-history modeling for

On the Psychometric Study of Human Life History Strategies.

Science.gov (United States)

Richardson, George B; Sanning, Blair K; Lai, Mark H C; Copping, Lee T; Hardesty, Patrick H; Kruger, Daniel J

2017-01-01

This article attends to recent discussions of validity in psychometric research on human life history strategy (LHS), provides a constructive critique of the extant literature, and describes strategies for improving construct validity. To place the psychometric study of human LHS on more solid ground, our review indicates that researchers should (a) use approaches to psychometric modeling that are consistent with their philosophies of measurement, (b) confirm the dimensionality of life history indicators, and (c) establish measurement invariance for at least a subset of indicators. Because we see confirming the dimensionality of life history indicators as the next step toward placing the psychometrics of human LHS on more solid ground, we use nationally representative data and structural equation modeling to test the structure of middle adult life history indicators. We found statistically independent mating competition and Super-K dimensions and the effects of parental harshness and childhood unpredictability on Super-K were consistent with past research. However, childhood socioeconomic status had a moderate positive effect on mating competition and no effect on Super-K, while unpredictability did not predict mating competition. We conclude that human LHS is more complex than previously suggested-there does not seem to be a single dimension of human LHS among Western adults and the effects of environmental components seem to vary between mating competition and Super-K.

On the Psychometric Study of Human Life History Strategies

Directory of Open Access Journals (Sweden)

George B. Richardson

2017-02-01

Full Text Available This article attends to recent discussions of validity in psychometric research on human life history strategy (LHS, provides a constructive critique of the extant literature, and describes strategies for improving construct validity. To place the psychometric study of human LHS on more solid ground, our review indicates that researchers should (a use approaches to psychometric modeling that are consistent with their philosophies of measurement, (b confirm the dimensionality of life history indicators, and (c establish measurement invariance for at least a subset of indicators. Because we see confirming the dimensionality of life history indicators as the next step toward placing the psychometrics of human LHS on more solid ground, we use nationally representative data and structural equation modeling to test the structure of middle adult life history indicators. We found statistically independent mating competition and Super-K dimensions and the effects of parental harshness and childhood unpredictability on Super-K were consistent with past research. However, childhood socioeconomic status had a moderate positive effect on mating competition and no effect on Super-K, while unpredictability did not predict mating competition. We conclude that human LHS is more complex than previously suggested—there does not seem to be a single dimension of human LHS among Western adults and the effects of environmental components seem to vary between mating competition and Super-K.

Behavioural mediators of genetic life-history trade-offs: a test of the pace-of-life syndrome hypothesis in field crickets.

Science.gov (United States)

Santostefano, Francesca; Wilson, Alastair J; Niemelä, Petri T; Dingemanse, Niels J

2017-10-11

The pace-of-life syndrome (POLS) hypothesis predicts associations between life history and 'risky' behaviours. Individuals with 'fast' lifestyles should develop faster, reproduce earlier, exhibit more risk-prone behaviours, and die sooner than those with 'slow' lifestyles. While support for POLS has been equivocal to date, studies have relied on individual-level (phenotypic) patterns in which genetic trade-offs may be masked by environmental effects on phenotypes. We estimated genetic correlations between life history (development, lifespan, size) and risky behaviours (exploration, aggression) in a pedigreed population of Mediterranean field crickets ( Gryllus bimaculatus ). Path analyses showed that behaviours mediated some genetic relationships between life history traits, though not those involved in trade-offs. Thus, while specific predictions of POLS theory were not supported, genetic integration of behaviour and life history was present. This implies a major role for risky behaviours in life history evolution. © 2017 The Author(s).

Life-history variation of a neotropical thrush challenges food limitation theory

Science.gov (United States)

Ferretti, V.; Llambias, P.E.; Martin, T.E.

2005-01-01

Since David Lack first proposed that birds rear as many young as they can nourish, food limitation has been accepted as the primary explanation for variation in clutch size and other life-history traits in birds. The importance of food limitation in life-history variation, however, was recently questioned on theoretical grounds. Here, we show that clutch size differences between two populations of a neotropical thrush were contrary to expectations under Lack's food limitation hypothesis. Larger clutch sizes were found in a population with higher nestling starvation rate (i.e. greater food limitation). We experimentally equalized clutches between populations to verify this difference in food limitation. Our experiment confirmed greater food limitation in the population with larger mean clutch size. In addition, incubation bout length and nestling growth rate were also contrary to predictions of food limitation theory. Our results demonstrate the inability of food limitation to explain differences in several life-history traits: clutch size, incubation behaviour, parental feeding rate and nestling growth rate. These life-history traits were better explained by inter-population differences in nest predation rates. Food limitation may be less important to life history evolution in birds than suggested by traditional theory. ?? 2005 The Royal Society.

What shall I do now? State-dependent variations of life-history traits with aging in Wandering Albatrosses.

Science.gov (United States)

Pardo, Deborah; Barbraud, Christophe; Weimerskirch, Henri

2014-02-01

Allocation decisions depend on an organism's condition which can change with age. Two opposite changes in life-history traits are predicted in the presence of senescence: either an increase in breeding performance in late age associated with terminal investment or a decrease due to either life-history trade-offs between current breeding and future survival or decreased efficiency at old age. Age variation in several life-history traits has been detected in a number of species, and demographic performances of individuals in a given year are influenced by their reproductive state the previous year. Few studies have, however, examined state-dependent variation in life-history traits with aging, and they focused mainly on a dichotomy of successful versus failed breeding and non-breeding birds. Using a 50-year dataset on the long-lived quasi-biennial breeding wandering albatross, we investigated variations in life-history traits with aging according to a gradient of states corresponding to potential costs of reproduction the previous year (in ascending order): non-breeding birds staying at sea or present at breeding grounds, breeding birds that failed early, late or were successful. We used multistate models to study survival and decompose reproduction into four components (probabilities of return, breeding, hatching, and fledging), while accounting for imperfect detection. Our results suggest the possible existence of two strategies in the population: strict biennial breeders that exhibited almost no reproductive senescence and quasi-biennial breeders that showed an increased breeding frequency with a strong and moderate senescence on hatching and fledging probabilities, respectively. The patterns observed on survival were contrary to our predictions, suggesting an influence of individual quality rather than trade-offs between reproduction and survival at late ages. This work represents a step further into understanding the evolutionary ecology of senescence and its

Labelling of end-of-life decisions by physicians

NARCIS (Netherlands)

Deyaert, J.; Chambaere, K.; Cohen, J.; Roelands, M.; Deliens, L.

2014-01-01

Objectives: Potentially life-shortening medical end-oflife practices (end-of-life decisions (ELDs)) remain subject to conceptual vagueness. This study evaluates how physicians label these practices by examining which of their own practices (described according to the precise act, the intention, the

Life History Consequences of the Facultative Expression of a Dispersal Life Stage in the Phoretic Bulb Mite (Rhizoglyphus robini.

Directory of Open Access Journals (Sweden)

Jacques A Deere

Full Text Available Life history traits play an important role in population dynamics and correlate, both positively and negatively, with dispersal in a wide range of taxa. Most invertebrate studies on trade-offs between life history traits and dispersal have focused on dispersal via flight, yet much less is known about how life history trade-offs influence species that disperse by other means. In this study, we identify effects of investing in dispersal morphology (dispersal expression on life history traits in the male dimorphic bulb mite (Rhizoglyphus robini. This species has a facultative juvenile life stage (deutonymph during which individuals can disperse by phoresy. Further, adult males are either fighters (which kill other mites or benign scramblers. Here, in an experiment, we investigate the effects of investing in dispersal on size at maturity, sex and male morph ratio, and female lifetime reproductive success. We show that life history traits correlate negatively with the expression of the dispersal stage. Remarkably, all males that expressed the dispersal life stage developed into competitive fighters and none into scramblers. This suggests that alternative, male reproductive strategies and dispersal should not be viewed in isolation but considered concurrently.

Evolutionary assembly rules for fish life histories

DEFF Research Database (Denmark)

Charnov, E.L.; Gislason, Henrik; Pope, J.G.

2012-01-01

length along the growth trajectory within the species. We then interpret K in terms of the VBGE in mass , and show that the previous equation is itself equivalent to a -1/3 power function rule between M and the mass at first reproduction (W α); this new -1/3 power function emerges directly from the life...... history that maximizes Darwinian fitness in non-growing populations. We merge this M, W α power function with other power functions to produce general across-species scaling rules for yearly reproductive allocation, reproductive effort and age at first reproduction in fish. We then suggest a new way...... to classify habitats (or lifestyles) as to the life histories they should contain, and we contrast our scheme with the widely used Winemiller-Rose fish lifestyle classification...

Sleep-Wake State Tradeoffs, Impulsivity and Life History Theory

Directory of Open Access Journals (Sweden)

Alissa A. Miller

2012-04-01

Full Text Available Evolutionary ecological theory predicts that sleep-wake state tradeoffs may be related to local environmental conditions and should therefore correlate to alterations in behavioral life history strategies. It was predicted that firefighters who slept more and reported better quality sleep on average would exhibit lower impulsivity inclinations related to slower life history trajectories. UPPS impulsivity scores and self-reported sleep averages were analyzed and indicated a negative association between sleep variables and urgency and a positive association with premeditation. Perseverance, and in some cases premeditation, however, disclosed an unpredicted marginally significant positive association between increased and emergency nighttime waking-related sleep deprivation. Sensation seeking was not associated with sleep variables, but was strongly associated with number of biological children. This research contributes to understanding the implications of human sleep across ecological and behavioral contexts and implies further research is necessary for constructing evolutionarily oriented measures of impulsivity inclination and its meaning in the context of life history strategies.

Daily life historyasmodern direction of urban history of Englandof High Middle Ages

Directory of Open Access Journals (Sweden)

O. S. Okhrimenko

2014-07-01

Full Text Available Historiographical review of recent research is an important aspect of the scientific study of the problems of medieval urban history of England. In 2000s there was marked the beginning of years of studying the history of everyday of medieval towns. The most important works in this field are the studies of Professor C. Dyer. Studying the history of everyday life of the city the researcher has identified as «standards of living». One of the modern directions of the history of everyday life is a history of food. There is the significant research of Professor M. Carlin on the history of English feasting of urban residents of the Middle Ages. In the article Fast food and urban living standards in medieval England, she looked anew at the narrative sources XII-XIV centuries. Another area of daily life history is a history of clothes (fashion. L. A. Wilson in his work De novo modo: The birth of fashion in the Middle Ages analyzes comprehensively the written, visual, and archaeological evidence. Modern interpretations of medieval hygiene (including sanitation of medieval towns related to research in the area of a history body. Its appointed destination for British urban sources dealing D. Jorgensen, D. Keene, U. Ewert, G. Geltner, J. Lee etc. They revised the traditional view medievalists of the nineteenth century. At the present period the historiography of medieval towns of England are mostly social history. Towards the history of everyday life there is a tendency to positive characteristics of urban life in the English Middle Ages. Contemporary scholars refer to the current trends in the world. Active urbanization processes forced researchers to seek appeal of such a way of life in previous centuries, particularly in the Middle Ages. The key features of everyday modern city (commercialization, fast food, fashion, high standards of hygiene etc. historians find their roots in the past.

Decision making across the life span

NARCIS (Netherlands)

Li, S.C.; Ridderinkhof, K.R.; Samanez-Larkin, G.R.

2014-01-01

Learning to choose adaptively between different behavioral options in order to reach goals is a pervasive task in life for people of all ages. Individuals are often confronted with complex, uncertain situations that nonetheless require decisive actions that would facilitate the pursuit of short-term

Linking habitat structure to life history strategy: Insights from a Mediterranean killifish

Science.gov (United States)

Cavraro, Francesco; Daouti, Irini; Leonardos, Ioannis; Torricelli, Patrizia; Malavasi, Stefano

2014-01-01

Modern theories of life history evolution deal with finding links between environmental factors, demographic structure of animal populations and the optimal life history strategy. Small-sized teleost fish, occurring in fragmented populations under contrasting environments, have been widely used as study models to investigate these issues. In the present study, the Mediterranean killifish Aphanius fasciatus was used to investigate the relationships between some habitat features and life history strategy. We selected four sites in the Venice lagoon inhabited by this species, exhibiting different combinations of two factors: overall adult mortality, related to intertidal water coverage and a consequent higher level of predator exposure, and the level of sediment organic matter, as indicator of habitat trophic richness. Results showed that these were the two most important factors influencing demography and life history traits in the four sites. Fish from salt marshes with high predator pressure were smaller and produced a higher number of eggs, whereas bigger fish and a lower reproductive investment were found in the two closed, not tidally influenced habitats. Habitat richness was positively related with population density, but negatively related with growth rate. In particular the synergy between high resources and low predation level was found to be important in shaping peculiar life history traits. Results were discussed in the light of the interactions between selective demographic forces acting differentially on age/size classes, such as predation, and habitat trophic richness that may represent an important energetic constraint on life history traits. The importance to link habitat productivity and morphology to demographic factors for a better understanding of the evolution of life history strategy under contrasting environments was finally suggested.

Nurse involvement in end-of-life decision making: the ETHICUS Study

DEFF Research Database (Denmark)

Benbenishty, Julie; Ganz, Freda DeKeyser; Lippert, Anne

2006-01-01

The purpose was to investigate physicians' perceptions of the role of European intensive care nurses in end-of-life decision making.......The purpose was to investigate physicians' perceptions of the role of European intensive care nurses in end-of-life decision making....

Dynamics of body time, social time and life history at adolescence.

Science.gov (United States)

Worthman, Carol M; Trang, Kathy

2018-02-21

Recent opposing trends towards earlier physical maturation and later social maturation present a conundrum of apparent biological-social mismatch. Here we use life history analysis from evolutionary ecology to identify forces that drive these shifts. Together with findings in developmental science, our life history analysis indicates that adolescence is a distinctive period for biological embedding of culture. Ethnographic evidence shows that mass education is a novel feature of the globalizing cultural configurations of adolescence, which are driven by transformations in labour, livelihood and lifestyle. Evaluation of the life history trade-offs and sociocultural ecologies that are experienced by adolescents may offer a practical basis for enhancing their development.

Dynamics of body time, social time and life history at adolescence

Science.gov (United States)

Worthman, Carol M.; Trang, Kathy

2018-02-01

Recent opposing trends towards earlier physical maturation and later social maturation present a conundrum of apparent biological-social mismatch. Here we use life history analysis from evolutionary ecology to identify forces that drive these shifts. Together with findings in developmental science, our life history analysis indicates that adolescence is a distinctive period for biological embedding of culture. Ethnographic evidence shows that mass education is a novel feature of the globalizing cultural configurations of adolescence, which are driven by transformations in labour, livelihood and lifestyle. Evaluation of the life history trade-offs and sociocultural ecologies that are experienced by adolescents may offer a practical basis for enhancing their development.

Dyadic fertility decisions in a life course perspective.

Science.gov (United States)

Bauer, Gerrit; Kneip, Thorsten

2014-09-01

This paper focuses on how couples arrive at joint decisions with regard to fertility behaviour. We build upon previous work on decision rules that couples might apply as heuristics in order to arrive at joint action in cases in which partners' fertility preferences differ. Previous research found either stronger effects of women's desires or symmetrical effects of both spouses' desires and net benefits associated with (further) children on proceptive behaviour. The latter finding is in line with the notion of household utility maximisation, in which both partners' preferences enter into a joint utility function with equal weight. On the other hand, some evidence indicates that one partner can exercise a 'veto' if he or she anticipates individual utility losses from a further child (due to opportunity costs arising in other life domains). We now enhance previous research by applying a life-course perspective. Our analysis makes use of variation in initial conditions due to previous births: couples decide on fertility in different situations as they find themselves in different life course stages and have had certain experiences. Parity-specific differences affect not only fertility outcomes but also the decision-making process itself. Our findings show that the decision to have a first child is made jointly, and each partner may exercise a veto. On the other hand, women appear to dominate decisions on higher parity births, not per se, but because they are (still) the ones more affected by the concomitant housework. Copyright © 2013 Elsevier Ltd. All rights reserved.

Protocol for implementation of family health history collection and decision support into primary care using a computerized family health history system

Directory of Open Access Journals (Sweden)

Agbaje Astrid B

2011-10-01

Full Text Available Abstract Background The CDC's Family History Public Health Initiative encourages adoption and increase awareness of family health history. To meet these goals and develop a personalized medicine implementation science research agenda, the Genomedical Connection is using an implementation research (T3 research framework to develop and integrate a self-administered computerized family history system with built-in decision support into 2 primary care clinics in North Carolina. Methods/Design The family health history system collects a three generation family history on 48 conditions and provides decision support (pedigree and tabular family history, provider recommendation report and patient summary report for 4 pilot conditions: breast cancer, ovarian cancer, colon cancer, and thrombosis. All adult English-speaking, non-adopted, patients scheduled for well-visits are invited to complete the family health system prior to their appointment. Decision support documents are entered into the medical record and available to provider's prior to the appointment. In order to optimize integration, components were piloted by stakeholders prior to and during implementation. Primary outcomes are change in appropriate testing for hereditary thrombophilia and screening for breast cancer, colon cancer, and ovarian cancer one year after study enrollment. Secondary outcomes include implementation measures related to the benefits and burdens of the family health system and its impact on clinic workflow, patients' risk perception, and intention to change health related behaviors. Outcomes are assessed through chart review, patient surveys at baseline and follow-up, and provider surveys. Clinical validity of the decision support is calculated by comparing its recommendations to those made by a genetic counselor reviewing the same pedigree; and clinical utility is demonstrated through reclassification rates and changes in appropriate screening (the primary outcome

A psycho-societal approach to life histories

DEFF Research Database (Denmark)

Olesen, Henning Salling

2016-01-01

Life histories represent lived lives past, present and anticipated future. As such they are interpretations of individuals’ experiences of the way in which societal dynamics take place in the individual body and mind, either by the individual him/herself or by another biographer. I have been...... particularly interested in the relations between the culturally mediated and the sensory/bodily aspects of experience processes because this is the boundary zones of knowledge and seat of the dynamics of learning. My psycho-societal approach was developing from interpreting autobiographical and later certain...... other forms of language interactive material as moments of life history, i.e. it is basically a hermeneutic approach. Talking about a psycho-societal approach indicates the ambition of attacking the dichotomy of the social and the psychic, both in the interpretation procedure and in some main...

Predicting life-history adaptations to pollutants

Energy Technology Data Exchange (ETDEWEB)

Maltby, L. [Univ. of Sheffield (United Kingdom). Dept. of Animal and Plant Sciences

1995-12-31

Animals may adapt to pollutant stress so that individuals from polluted environments are less susceptible than those from unpolluted environments. In addition to such direct adaptations, animals may respond to pollutant stress by life-history modifications; so-called indirect adaptations. This paper will demonstrate how, by combining life-history theory and toxicological data, it is possible to predict stress-induced alterations in reproductive output and offspring size. Pollutant-induced alterations in age-specific survival in favor of adults and reductions in juvenile growth, conditions are predicted to select for reduced investment in reproduction and the allocation of this investment into fewer, larger offspring. Field observations on the freshwater crustaceans, Asellus aquaticus and Gammarus pulex, support these predictions. Females from metal-polluted sites had lower investment in reproduction and produced larger offspring than females of the same species from unpolluted sites. Moreover, interpopulation differences in reproductive biology persisted in laboratory cultures indicating that they had a genetic basis and were therefore due to adaptation rather than acclimation. The general applicability of this approach will be considered.

Host responses in life-history traits and tolerance to virus infection in Arabidopsis thaliana.

Directory of Open Access Journals (Sweden)

Israel Pagán

2008-08-01

Full Text Available Knowing how hosts respond to parasite infection is paramount in understanding the effects of parasites on host populations and hence host-parasite co-evolution. Modification of life-history traits in response to parasitism has received less attention than other defence strategies. Life-history theory predicts that parasitised hosts will increase reproductive effort and accelerate reproduction. However, empirical analyses of these predictions are few and mostly limited to animal-parasite systems. We have analysed life-history trait responses in 18 accessions of Arabidopsis thaliana infected at two different developmental stages with three strains of Cucumber mosaic virus (CMV. Accessions were divided into two groups according to allometric relationships; these groups differed also in their tolerance to CMV infection. Life-history trait modification upon virus infection depended on the host genotype and the stage at infection. While all accessions delayed flowering, only the more tolerant allometric group modified resource allocation to increase the production of reproductive structures and progeny, and reduced the length of reproductive period. Our results are in agreement with modifications of life-history traits reported for parasitised animals and with predictions from life-history theory. Thus, we provide empirical support for the general validity of theoretical predictions. In addition, this experimental approach allowed us to quantitatively estimate the genetic determinism of life-history trait plasticity and to evaluate the role of life-history trait modification in defence against parasites, two largely unexplored issues.

A decision-making framework for effective maintenance management using life cycle costing (LCC in a rolling stock environment

Directory of Open Access Journals (Sweden)

Fourie, Cornelius Jacobus

2016-12-01

Full Text Available In this paper, a life cycle costing (LCC framework for effective maintenance management is investigated and developed for use in a railway rolling stock environment. The framework consists of combining typical mission-critical components together with their failure and maintenance history. All costs related to the operation and maintenance of these components throughout their life cycle are also determined. The next step involves considering different scenarios under which the components can be used in relation to operations, maintenance, and replacements. The decision about which scenario to take is based on the one with the most favourable net present value after life cycle costing is performed over a specified period of time. A typical railway rolling-stock maintenance organisation in South Africa was used to highlight the practical implications of such a framework and how the company could make informed and appropriate decisions. The conclusion of this study is that such a framework is useful, and that it can be used as a basis for estimating LCC across a spectrum of critical assets found in the rolling stock environment.

Using Age-Based Life History Data to Investigate the Life Cycle and Vulnerability of Octopus cyanea

Science.gov (United States)

Herwig, Jade N.; Depczynski, Martial; Roberts, John D.; Semmens, Jayson M.; Gagliano, Monica; Heyward, Andrew J.

2012-01-01

Octopus cyanea is taken as an unregulated, recreationally fished species from the intertidal reefs of Ningaloo, Western Australia. Yet despite its exploitation and importance in many artisanal fisheries throughout the world, little is known about its life history, ecology and vulnerability. We used stylet increment analysis to age a wild O. cyanea population for the first time and gonad histology to examine their reproductive characteristics. O. cyanea conforms to many cephalopod life history generalisations having rapid, non-asymptotic growth, a short life-span and high levels of mortality. Males were found to mature at much younger ages and sizes than females with reproductive activity concentrated in the spring and summer months. The female dominated sex-ratios in association with female brooding behaviours also suggest that larger conspicuous females may be more prone to capture and suggests that this intertidal octopus population has the potential to be negatively impacted in an unregulated fishery. Size at age and maturity comparisons between our temperate bordering population and lower latitude Tanzanian and Hawaiian populations indicated stark differences in growth rates that correlate with water temperatures. The variability in life history traits between global populations suggests that management of O. cyanea populations should be tailored to each unique set of life history characteristics and that stylet increment analysis may provide the integrity needed to accurately assess this. PMID:22912898

Evolution of monogamy, paternal investment, and female life history in Peromyscus.

Science.gov (United States)

Jašarević, Eldin; Bailey, Drew H; Crossland, Janet P; Dawson, Wallace D; Szalai, Gabor; Ellersieck, Mark R; Rosenfeld, Cheryl S; Geary, David C

2013-02-01

The timing of reproductive development and associated trade-offs in quantity versus quality of offspring produced across the life span are well documented in a wide range of species. The relation of these aspects of maternal life history to monogamy and paternal investment in offspring is not well studied in mammals, due in part to the rarity of the latter. By using five large, captive-bred populations of Peromyscus species that range from promiscuous mating with little paternal investment (P. maniculatus bairdii) to social and genetic monogamy with substantial paternal investment (P. californicus insignis), we modeled the interaction between monogamy and female life history. Monogamy and high paternal investment were associated with smaller litter size, delayed maternal reproduction that extended over a longer reproductive life span, and larger, higher quality offspring. The results suggest monogamy and paternal investment can alter the evolution of female life-history trajectories in mammals. PsycINFO Database Record (c) 2013 APA, all rights reserved

A Life History of a Korean Adolescent Girl Who Attempted Suicide

Science.gov (United States)

Yang, Sungeun

2012-01-01

The present study explores the life history of a South Korean adolescent girl who attempted suicide. The study focuses on how sociocultural values affected her suicide attempt and how she made meaning out of the experience. The results revealed that her life history was a process of seeking independence and autonomy, and freeing herself from…

The role of life histories and trophic interactions in population recovery.

Science.gov (United States)

Audzijonyte, Asta; Kuparinen, Anna

2016-08-01

Factors affecting population recovery from depletion are at the focus of wildlife management. Particularly, it has been debated how life-history characteristics might affect population recovery ability and productivity. Many exploited fish stocks have shown temporal changes towards earlier maturation and reduced adult body size, potentially owing to evolutionary responses to fishing. Whereas such life-history changes have been widely documented, their potential role on stock's ability to recover from exploitation often remains ignored by traditional fisheries management. We used a marine ecosystem model parameterized for Southeastern Australian ecosystem to explore how changes towards "faster" life histories might affect population per capita growth rate r. We show that for most species changes towards earlier maturation during fishing have a negative effect (3-40% decrease) on r during the recovery phase. Faster juvenile growth and earlier maturation were beneficial early in life, but smaller adult body sizes reduced the lifetime reproductive output and increased adult natural mortality. However, both at intra- and inter-specific level natural mortality and trophic position of the species were as important in determining r as species longevity and age of maturation, suggesting that r cannot be predicted from life-history traits alone. Our study highlights that factors affecting population recovery ability and productivity should be explored in a multi-species context, where both age-specific fecundity and survival schedules are addressed simultaneously. It also suggests that contemporary life-history changes in harvested species are unlikely to increase their resilience and recovery ability. © 2016 Society for Conservation Biology.

Effects of maternal history of depression and early life maltreatment on children's health-related quality of life.

Science.gov (United States)

Dittrich, Katja; Fuchs, Anna; Bermpohl, Felix; Meyer, Justus; Führer, Daniel; Reichl, Corinna; Reck, Corinna; Kluczniok, Dorothea; Kaess, Michael; Hindi Attar, Catherine; Möhler, Eva; Bierbaum, Anna-Lena; Zietlow, Anna-Lena; Jaite, Charlotte; Winter, Sibylle Maria; Herpertz, Sabine C; Brunner, Romuald; Bödeker, Katja; Resch, Franz

2018-01-01

There is a well-established link between maternal depression and child mental health. Similar effects have been found for maternal history of early life maltreatment (ELM). However, studies investigating the relationship of children's quality of life and maternal depression are scarce and none have been conducted for the association with maternal ELM. The aim of the present study was to investigate the effects of maternal history of ELM and depression on children's health-related quality of life and to identify mediating factors accounting for these effects. Our study involved 194 mothers with and without history of depression and/or ELM and their children between five and 12 years. Children's health-related quality of life was assessed by maternal proxy- and child self-ratings using the KIDSCREEN. We considered maternal sensitivity and maternal parenting stress as potential mediators. We found an effect of maternal history of depression but not of maternal history of ELM on health-related quality of life. Maternal stress and sensitivity mediated the effects of maternal depression on child global health-related quality of life, as well as on the dimensions Autonomy & Parent Relation, School Environment (maternal and child rating), and Physical Wellbeing (child rating). Due to the cross-sectional design of the study, causal interpretations must be made with caution. Some scales yielded low internal consistency. Maternal impairments in areas of parenting which possibly developed during acute depression persist even after remission of acute affective symptoms. Interventions should target parenting stress and sensitivity in parents with prior depression. Copyright © 2017 Elsevier B.V. All rights reserved.

Histoires de vie et Formation de Nouveaux Savoirs Vitaux (Life Histories and the Formation of New Life Knowledge).

Science.gov (United States)

Pineau, Gaston

1994-01-01

Describes the use of life histories as a means for making sense of personal events and their application to education. Distinguishes three models for the use of life histories in education: the biographical model, the autobiographical model, and the dialectical model. (22 citations) (MAB)

Medical futility in children's nursing: making end-of-life decisions.

Science.gov (United States)

Brien, Irene O; Duffy, Anita; Shea, Ellen O

Caring for infants at end of life is challenging and distressing for parents and healthcare professionals, especially in relation to making decisions regarding withholding or withdrawal of treatment. The concept of medical futility must be considered under these circumstances. Parents and healthcare professionals should be involved together in making these difficult decisions. However, for some parents, emotions and guilt often are unbearable and, understandably, parents can be reluctant to make a decision. Despite the recognition of parental autonomy, if parents disagree with a decision made by medical staff, the case will be referred to and solved by the courts. The courts' decisions are often based on the best interest of the child. In this article, the authors discuss the concepts of 'parental autonomy' and 'the child's best interests' when determining medical futility for infants or neonates. The role of the nurse when caring for the dying child and their family is multifaceted. While nurses do not have a legitimate role in decision making at the end of life, it is often nurses who, through their advocacy role, inform doctors about parents' wishes and it is often nurses who support parents during this difficult time. Furthermore, nurses caring for dying children should be familiar to the family, experienced in end-of-life care and comfortable talking to parents about death and dying and treatment choices. Children's nurses therefore require advanced communication skills and an essential understanding of the ethical and legal knowledge relating to medical futility in end-of-life children's nursing.

Medical futility in children's nursing: making end-of-life decisions.

LENUS (Irish Health Repository)

Brien, Irene O

2012-02-01

Caring for infants at end of life is challenging and distressing for parents and healthcare professionals, especially in relation to making decisions regarding withholding or withdrawal of treatment. The concept of medical futility must be considered under these circumstances. Parents and healthcare professionals should be involved together in making these difficult decisions. However, for some parents, emotions and guilt often are unbearable and, understandably, parents can be reluctant to make a decision. Despite the recognition of parental autonomy, if parents disagree with a decision made by medical staff, the case will be referred to and solved by the courts. The courts\\' decisions are often based on the best interest of the child. In this article, the authors discuss the concepts of \\'parental autonomy\\' and \\'the child\\'s best interests\\' when determining medical futility for infants or neonates. The role of the nurse when caring for the dying child and their family is multifaceted. While nurses do not have a legitimate role in decision making at the end of life, it is often nurses who, through their advocacy role, inform doctors about parents\\' wishes and it is often nurses who support parents during this difficult time. Furthermore, nurses caring for dying children should be familiar to the family, experienced in end-of-life care and comfortable talking to parents about death and dying and treatment choices. Children\\'s nurses therefore require advanced communication skills and an essential understanding of the ethical and legal knowledge relating to medical futility in end-of-life children\\'s nursing.

Fast-slow continuum and reproductive strategies structure plant life-history variation worldwide.

Science.gov (United States)

Salguero-Gómez, Roberto; Jones, Owen R; Jongejans, Eelke; Blomberg, Simon P; Hodgson, David J; Mbeau-Ache, Cyril; Zuidema, Pieter A; de Kroon, Hans; Buckley, Yvonne M

2016-01-05

The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous variation in life history are poorly understood. We use demographic data from 418 plant species in the wild, from annual herbs to supercentennial trees, to examine how growth form, habitat, and phylogenetic relationships structure plant life histories and to develop a framework to predict population performance. We show that 55% of the variation in plant life-history strategies is adequately characterized using two independent axes: the fast-slow continuum, including fast-growing, short-lived plant species at one end and slow-growing, long-lived species at the other, and a reproductive strategy axis, with highly reproductive, iteroparous species at one extreme and poorly reproductive, semelparous plants with frequent shrinkage at the other. Our findings remain consistent across major habitats and are minimally affected by plant growth form and phylogenetic ancestry, suggesting that the relative independence of the fast-slow and reproduction strategy axes is general in the plant kingdom. Our findings have similarities with how life-history strategies are structured in mammals, birds, and reptiles. The position of plant species populations in the 2D space produced by both axes predicts their rate of recovery from disturbances and population growth rate. This life-history framework may complement trait-based frameworks on leaf and wood economics; together these frameworks may allow prediction of responses of plants to anthropogenic disturbances and changing environments.

Real-life decision making in college students. I: Consistency across specific decisions.

Science.gov (United States)

Galotti, Kathleen M; Wiener, Hillary J D; Tandler, Jane M

2014-01-01

First-year undergraduates participated in a short-term longitudinal study of real-life decision making over their first 14 months of college. They were surveyed about 7 different decisions: choosing courses for an upcoming term (3 different terms), choosing an academic major (twice), planning for the upcoming summer, and planning for sophomore-year housing. Participants showed moderate levels of consistency in the options they considered and in the criteria they used to decide between options, with about half of the options or criteria being used at 2 different points on the decision repeatedly studied. Participants varied somewhat in structural consistency, the tendency to consider the same number of options or criteria across decisions. They also varied in the way they integrated information across decision-making tasks. We suggest that people attempt to keep the information demands of the task within workable limits, sometimes sacrificing consistency as a result.

Life History Theory and Social Deviance: The Mediating Role of Executive Function

Science.gov (United States)

Wenner, C. J.; Bianchi, J.; Figueredo, A. J.; Rushton, J. Philippe; Jacobs, W. J.

2013-01-01

The present work examined predicted relations among Life History strategies, Executive Functions, socially antagonistic attitudes, socially antagonistic behaviors, and general intelligence. Life History (LH) theory predicts that Executive Functions and socially antagonistic attitudes and behaviors underpin an interrelated and coherent set of…

Plant life history and above–belowground interactions

NARCIS (Netherlands)

Deyn, de Gerlinde

2017-01-01

The importance of above–belowground interactions for plant growth and community dynamics became clear in the last decades, whereas the numerous studies on plant life history improved our knowledge on eco-evolutionary dynamics. However, surprisingly few studies have linked both research fields

Telling Modernization: Three Voices. Life History, Gender and the Discourse of Modernization. Roskilde University Life History Project Paper.

Science.gov (United States)

Anderson, Linda

The relationship between life history, gender, and the discourse of modernization was examined from the perspective of a researcher with extensive experience performing evaluations about modernization within human services in Denmark. Three stories about site-based management in two human service institutionsa youth center and a boarding school…

Early-Life Characteristics, Psychiatric History, and Cognition Trajectories in Later Life

Science.gov (United States)

Brown, Maria Teresa

2010-01-01

Purpose of the Study: Although considerable attention has been paid to the relationship between later-life depression and cognitive function, the relationship between a history of psychiatric problems and cognitive function is not very well documented. Few studies of relationships between childhood health, childhood disadvantage, and cognitive…

The association between parental life history and offspring phenotype in Atlantic salmon.

Science.gov (United States)

Van Leeuwen, Travis E; McLennan, Darryl; McKelvey, Simon; Stewart, David C; Adams, Colin E; Metcalfe, Neil B

2016-02-01

In many taxa there is considerable intraspecific variation in life history strategies from within a single population, reflecting alternative routes through which organisms can achieve successful reproduction. Atlantic salmon Salmo salar (Linnaeus) show some of the greatest within-population variability in life history strategies amongst vertebrates, with multiple discrete male and female life histories co-existing and interbreeding on many spawning grounds, although the effect of the various combinations of life histories on offspring traits remains unknown. Using crosses of wild fish we show here that the life history strategy of both parents was significantly associated with a range of offspring traits. Mothers that had spent longer at sea (2 versus 1 year) produced offspring that were heavier, longer and in better condition at the time of first feeding. However, these relationships disappeared shortly after fry had begun feeding exogenously. At this stage, the juvenile rearing environment (i.e. time spent in fresh water as juveniles) of the mother was a better predictor of offspring traits, with mothers that were faster to develop in fresh water (migrating to sea after two rather than three years of age) producing offspring that had higher maximal metabolic rates, aerobic scopes, and that grew faster. Faster developing fathers (1 year old sneaker males) tended to produce offspring that had higher maximal metabolic rates, were in better body condition and grew faster. The results suggest that both genetic effects and those related to parental early and late life history contribute to offspring traits. © 2016. Published by The Company of Biologists Ltd.

Economic modelling for life extension decision making

International Nuclear Information System (INIS)

Farber, M.A.; Harrison, D.L.; Carlson, D.D.

1987-01-01

This paper presents a methodology for the economic and financial analysis of nuclear plant life extension under uncertainty and demonstrates its use in a case analysis. While the economic and financial evaluation of life extension does not require new analytical tools, such studies should be based on the following three premises. First, the methodology should examine effects at the level of the company or utility system, because the most important economic implications of life extension relate to the altered generation system expansion plan. Second, it should focus on the implications of uncertainty in order to understand the factors that most affect life extension benefits and identify risk management efforts. Third, the methodology should address multiple objectives, at a minimum, both economic and financial objectives. An analysis of the role of life extension for Virginia Power's generating system was performed using the MIDAS model, developed by the Electric Power Research Institute. MIDAS is particularly well suited to this type of study because of its decision analysis framework. The model incorporates modules for load analysis, capacity expansion, production costing, financial analysis, and rates. The decision tree structure facilitates the multiple-scenario analysis of uncertainty. The model's output includes many economic and financial measures, including capital expenditures, fuel and purchases power costs, revenue requirements, average rates, external financing requirements, and coverage ratio. Based on findings for Virginia Power's Surry 1 plant, nuclear plant life extension has economic benefits for a utility's customers and financial benefits for the utility's investors. These benefits depend on a number of economic, technical and regulatory factors. The economic analysis presented in this paper identifies many of the key factors and issues relevant to life extension planning

Life-history parameters of white stumpnose Rhabdosargus ...

African Journals Online (AJOL)

Life-history parameters of white stumpnose Rhabdosargus globiceps (Pisces: Sparidae) in Saldanha Bay, South Africa, with evidence of stock separation. ... Seasonal variation in the condition index suggests a slightly greater investment in reproduction by males than females. Females grew slightly faster than males and ...

Can understanding squid life-history strategies and recruitment ...

African Journals Online (AJOL)

Can understanding squid life-history strategies and recruitment improve management? ... range of potentially limiting conditions in different years, they store genetic diversity and stabilize recruitment in time. ... AJOL African Journals Online.

Do pioneers have r-selected traits? Life history patterns among colonizing terrestrial gastropods.

Science.gov (United States)

Bengtsson, J; Baur, B

1993-05-01

We examine whether pioneer species of terrestrial gastropods (snails and slugs) possess particular life history traits commonly associated with r-selection, using data on gastropod colonization in four areas in north-west Europe (the Kvarken and Tvärminne archipelagos in the Baltic, polder woods in IJsselmeer, and a rehabilitated quarry near Maastricht). Data on age at first reproduction, longevity, clutch size, egg size and lifetime fecundity were gathered from the literature. In order to control for potentially confounding effects of body size on life history traits, we compared the residuals from the allometric relations between life history traits and body size for pioneers and non-pioneers. In snails, all life history traits examined were related to body size. In slugs, all traits except age at first reproduction scaled with body size. Body sizes did not differ between pioneers and non-pioneers in any area. In all four areas, there were no significant differences between pioneers and non-pioneers in any of the life history traits examined, after body size had been taken into account. This indicates that pioneer terrestrial gastropods generally cannot be regarded as r-selected. Pioneer species may possess any of several life history strategies, and the combinations of traits shown by them may have little in common with the r-K selection concept.

Connecting proximate mechanisms and evolutionary patterns: pituitary gland size and mammalian life history.

Science.gov (United States)

Kamilar, J M; Tecot, S R

2015-11-01

At the proximate level, hormones are known to play a critical role in influencing the life history of mammals, including humans. The pituitary gland is directly responsible for producing several hormones, including those related to growth and reproduction. Although we have a basic understanding of how hormones affect life history characteristics, we still have little knowledge of this relationship in an evolutionary context. We used data from 129 mammal species representing 14 orders to investigate the relationship between pituitary gland size and life history variation. Because pituitary gland size should be related to hormone production and action, we predicted that species with relatively large pituitaries should be associated with fast life histories, especially increased foetal and post-natal growth rates. Phylogenetic analyses revealed that total pituitary size and the size of the anterior lobe of the pituitary significantly predicted a life history axis that was correlated with several traits including body mass, and foetal and post-natal growth rates. Additional models directly examining the association between relative pituitary size and growth rates produced concordant results. We also found that relative pituitary size variation across mammals was best explained by an Ornstein-Uhlenbeck model of evolution, suggesting an important role of stabilizing selection. Our results support the idea that the size of the pituitary is linked to life history variation through evolutionary time. This pattern is likely due to mediating hormone levels but additional work is needed. We suggest that future investigations incorporating endocrine gland size may be critical for understanding life history evolution. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Life history tradeoffs of pathogens and the treatment principle of antibiogenesis

Directory of Open Access Journals (Sweden)

Rui-An Wang

2017-09-01

Full Text Available There are no eternal individual lives so life continues by relaying with reproduction. Consequently, lifespan and fecundity are two essential genetic traits of life. The life history tradeoffs theory holds that there is an inverse relationship between lifespan and fecundity. This paper proposes two new concepts, i.e., “lifespan of pathogens” and treatment of infections by “antibiogenesis”. The lifespan of pathogens is the time limitation of those tiny lives just as other large creatures. Notably, the lifespan of bacterium is the time interval from the cell division by which it is produced to next division by then its life ends and transforms to two new lives, or dies. Antibiogenesis means inhibiting generation of new lives. By the principle of life history tradeoffs, the lifespan of pathogens determines the speed of their proliferations and consequently the modality of infection. The treatment principle of antibiogenesis requires the duration of treatment to be determined by the lifespan of infected pathogens. The life history tradeoffs theory and the two concepts are helpful to understanding the pathobiology and shaping the clinical aspects of infectious diseases.

Phytoplankton models and life history strategies | Eilertsen | African ...

African Journals Online (AJOL)

Phytoplankton models and life history strategies. ... Chaetoceros bloom of the growth season usually starts in mid March, initiated by C. socialis. ... in some species, inoculation events are controlled by endogenous biological clocks.

Attitudes of Dutch nurses towards their involvement in end-of-life decisions with a possible life-shortening effect.

NARCIS (Netherlands)

Albers, G.; Francke, A.L.; Veer, A.J. de; Onwuteaka-Philipsen, B.D.

2012-01-01

Background: Nurses are often involved in end-of-life decision making as they play an important role in caring for terminally ill patients. Aim: To investigate nurses’ attitudes towards their involvement in end-of-life decisions with a possible lifeshortening effect, and a possible relationship with

Dissecting molecular stress networks: identifying nodes of divergence between life-history phenotypes.

Science.gov (United States)

Schwartz, Tonia S; Bronikowski, Anne M

2013-02-01

The complex molecular network that underlies physiological stress response is comprised of nodes (proteins, metabolites, mRNAs, etc.) whose connections span cells, tissues and organs. Variable nodes are points in the network upon which natural selection may act. Thus, identifying variable nodes will reveal how this molecular stress network may evolve among populations in different habitats and how it might impact life-history evolution. Here, we use physiological and genetic assays to test whether laboratory-born juveniles from natural populations of garter snakes (Thamnophis elegans), which have diverged in their life-history phenotypes, vary concomitantly at candidate nodes of the stress response network, (i) under unstressed conditions and (ii) in response to an induced stress. We found that two common measures of stress (plasma corticosterone and liver gene expression of heat shock proteins) increased under stress in both life-history phenotypes. In contrast, the phenotypes diverged at four nodes both under unstressed conditions and in response to stress: circulating levels of reactive oxygen species (superoxide, H(2)O(2)); liver gene expression of GPX1 and erythrocyte DNA damage. Additionally, allele frequencies for SOD2 diverge from neutral markers, suggesting diversifying selection on SOD2 alleles. This study supports the hypothesis that these life-history phenotypes have diverged at the molecular level in how they respond to stress, particularly in nodes regulating oxidative stress. Furthermore, the differences between the life-history phenotypes were more pronounced in females. We discuss the responses to stress in the context of the associated life-history phenotype and the evolutionary pressures thought to be responsible for divergence between the phenotypes. © 2012 Blackwell Publishing Ltd.

Generation time, life history and the substitution rate of neutral mutations.

Science.gov (United States)

Lehtonen, Jussi; Lanfear, Robert

2014-11-01

Our understanding of molecular evolution is hampered by a lack of quantitative predictions about how life-history (LH) traits should correlate with substitution rates. Comparative studies have shown that neutral substitution rates vary substantially between species, and evidence shows that much of this diversity is associated with variation in LH traits. However, while these studies often agree, some unexplained and contradictory results have emerged. Explaining these results is difficult without a clear theoretical understanding of the problem. In this study, we derive predictions for the relationships between LH traits and substitution rates in iteroparous species by using demographic theory to relate commonly measured life-history traits to genetic generation time, and by implication to neutral substitution rates. This provides some surprisingly simple explanations for otherwise confusing patterns, such as the association between fecundity and substitution rates. The same framework can be applied to more complex life histories if full life-tables are available. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Consilience and Life History Theory: From Genes to Brain to Reproductive Strategy

Science.gov (United States)

Figueredo, Aurelio Jose; Vasquez, Geneva; Brumbach, Barbara H.; Schneider, Stephanie M. R.; Sefcek, Jon A.; Tal, Ilanit R.; Hill, Dawn; Wenner, Christopher J.; Jacobs, W. Jake

2006-01-01

We describe an integrated theory of individual differences that traces the behavioral development of life history from genes to brain to reproductive strategy. We provide evidence that a single common factor, the K-Factor, underpins a variety of life-history parameters, including an assortment of sexual, reproductive, parental, familial, and…

Evolution of boldness and life-history in response to selective harvesting

DEFF Research Database (Denmark)

Andersen, Ken Haste; Marty, Lise; Arlinghaus, Robert

2018-01-01

Whether intensive harvesting alters the behavioral repertoire of exploited fishes is currently unknown, but plausible. We extend a fish life-history model to account for boldness as a personality trait that affects foraging intensity, which affects energy intake and risk from predation and fishing...... gear. We systematically investigate life-history and behavioral trait evolution along the boldness–timidity axis in response to the full range of common selectivity and exploitation patterns in fisheries. In agreement with previous studies, we find that any type of harvesting selects for fast life...... histories and that merely elevated, yet unselective, fishing mortality favors boldness. We also find that timid-selective fishing (which can be expected in species targeted by active gear types) selects for increased boldness. By contrast, increased timidity is predicted when fishing targets bolder...

Brief Self-Report Scales Assessing Life History Dimensions of Mating and Parenting Effort

Directory of Open Access Journals (Sweden)

Daniel J. Kruger

2017-02-01

Full Text Available Life history theory (LHT is a powerful evolutionary framework for understanding physiological, psychological, and behavioral variation both between and within species. Researchers and theorists are increasingly integrating LHT into evolutionary psychology, as it provides a strong foundation for research across many topical areas. Human life history variation has been represented in psychological and behavioral research in several ways, including indicators of conditions in the developmental environment, indicators of conditions in the current environment, and indicators of maturation and life milestones (e.g., menarche, initial sexual activity, first pregnancy, and in self-report survey scale measures. Survey scale measures have included constructs such as time perspective and future discounting, although the most widely used index is a constellation of indicators assessing the K-factor, thought to index general life history speed (from fast to slow. The current project examined the utility of two brief self-report survey measures assessing the life history dimensions of mating effort and parenting effort with a large undergraduate sample in the United States. Consistent with the theory, items reflected two inversely related dimensions. In regressions including the K-factor, the Mating Effort Scale proved to be a powerful predictor of other constructs and indicators related to life history variation. The Parenting Effort Scale had less predictive power overall, although it explained unique variance across several constructs and was the only unique predictor of the number of long-term (serious and committed relationships. These scales may be valuable additions to self-report survey research projects examining life history variation.

Hormonal correlates of male life history stages in wild white-faced capuchin monkeys (Cebus capucinus).

Science.gov (United States)

Jack, Katharine M; Schoof, Valérie A M; Sheller, Claire R; Rich, Catherine I; Klingelhofer, Peter P; Ziegler, Toni E; Fedigan, Linda

2014-01-01

Much attention has been paid to hormonal variation in relation to male dominance status and reproductive seasonality, but we know relatively little about how hormones vary across life history stages. Here we examine fecal testosterone (fT), dihydrotestosterone (fDHT), and glucocorticoid (fGC) profiles across male life history stages in wild white-faced capuchins (Cebus capucinus). Study subjects included 37 males residing in three habituated social groups in the Área de Conservacíon Guanacaste, Costa Rica. Male life history stages included infant (0 to Life history stage was a significant predictor of fT; levels were low throughout the infant and juvenile phases, doubled in subadult and subordinate adults, and were highest for alpha males. Life history stage was not a significant predictor of fDHT, fDHT:fT, or fGC levels. Puberty in white-faced capuchins appears to begin in earnest during the subadult male phase, indicated by the first significant rise in fT. Given their high fT levels and exaggerated secondary sexual characteristics, we argue that alpha adult males represent a distinctive life history stage not experienced by all male capuchins. This study is the first to physiologically validate observable male life history stages using patterns of hormone excretion in wild Neotropical primates, with evidence for a strong association between fT levels and life history stage. Copyright © 2013 Elsevier Inc. All rights reserved.

Decision-making heuristics and biases across the life span

Science.gov (United States)

Strough, JoNell; Karns, Tara E.; Schlosnagle, Leo

2013-01-01

We outline a contextual and motivational model of judgment and decision-making (JDM) biases across the life span. Our model focuses on abilities and skills that correspond to deliberative, experiential, and affective decision-making processes. We review research that addresses links between JDM biases and these processes as represented by individual differences in specific abilities and skills (e.g., fluid and crystallized intelligence, executive functioning, emotion regulation, personality traits). We focus on two JDM biases—the sunk-cost fallacy (SCF) and the framing effect. We trace the developmental trajectory of each bias from preschool through middle childhood, adolescence, early adulthood, and later adulthood. We conclude that life-span developmental trajectories differ depending on the bias investigated. Existing research suggests relative stability in the framing effect across the life span and decreases in the SCF with age, including in later life. We highlight directions for future research on JDM biases across the life span, emphasizing the need for process-oriented research and research that increases our understanding of JDM biases in people’s everyday lives. PMID:22023568

Decision-making heuristics and biases across the life span.

Science.gov (United States)

Strough, Jonell; Karns, Tara E; Schlosnagle, Leo

2011-10-01

We outline a contextual and motivational model of judgment and decision-making (JDM) biases across the life span. Our model focuses on abilities and skills that correspond to deliberative, experiential, and affective decision-making processes. We review research that addresses links between JDM biases and these processes as represented by individual differences in specific abilities and skills (e.g., fluid and crystallized intelligence, executive functioning, emotion regulation, personality traits). We focus on two JDM biases-the sunk-cost fallacy (SCF) and the framing effect. We trace the developmental trajectory of each bias from preschool through middle childhood, adolescence, early adulthood, and later adulthood. We conclude that life-span developmental trajectories differ depending on the bias investigated. Existing research suggests relative stability in the framing effect across the life span and decreases in the SCF with age, including in later life. We highlight directions for future research on JDM biases across the life span, emphasizing the need for process-oriented research and research that increases our understanding of JDM biases in people's everyday lives. © 2011 New York Academy of Sciences.

Life history and population dynamics of an estuarine amphipod, Eriopisa chilkensis Chilton (Gammaridae)

Digital Repository Service at National Institute of Oceanography (India)

Aravind, N.P.; Sheeba, P.; Nair, K.K.C.; Achuthankutty, C.T.

Life history and Population Dynamics of an Estuarine Amphipod –Eriopisa chilkensis Chilton (Gammaridae) Nisha. P. Aravind, P. Sheeba, K.K.C. Nair and C.T.Achuthankutty* National Institute of Oceanography, Regional Centre, Cochin 682018, India... of laboratory data to the field suggests that E. chilkensis in Cochin estuary has a multivoltine life cycle. Key words: - Eriopisa chilkensis, Amphipoda, life cycle, population dynamics, Cochin estuary, India 2 1. Introduction Life-history traits of 214 amphipod...

Material security, life history, and moralistic religions: A cross-cultural examination

Science.gov (United States)

Ross, Cody T.; Apicella, Coren; Atkinson, Quentin D.; Cohen, Emma; McNamara, Rita Anne; Willard, Aiyana K.; Xygalatas, Dimitris; Norenzayan, Ara; Henrich, Joseph

2018-01-01

Researchers have recently proposed that “moralistic” religions—those with moral doctrines, moralistic supernatural punishment, and lower emphasis on ritual—emerged as an effect of greater wealth and material security. One interpretation appeals to life history theory, predicting that individuals with “slow life history” strategies will be more attracted to moralistic traditions as a means to judge those with “fast life history” strategies. As we had reservations about the validity of this application of life history theory, we tested these predictions with a data set consisting of 592 individuals from eight diverse societies. Our sample includes individuals from a wide range of traditions, including world religions such as Buddhism, Hinduism and Christianity, but also local traditions rooted in beliefs in animism, ancestor worship, and worship of spirits associated with nature. We first test for the presence of associations between material security, years of formal education, and reproductive success. Consistent with popular life history predictions, we find evidence that material security and education are associated with reduced reproduction. Building on this, we then test whether or not these demographic factors predict the moral concern, punitiveness, attributed knowledge-breadth, and frequency of ritual devotions towards two deities in each society. Here, we find no reliable evidence of a relationship between number of children, material security, or formal education and the individual-level religious beliefs and behaviors. We conclude with a discussion of why life-history theory is an inadequate interpretation for the emergence of factors typifying the moralistic traditions. PMID:29513766

Prey nutrient composition has different effects on Pardosa wolf spiders with dissimilar life histories

DEFF Research Database (Denmark)

Jensen, Kim; Mayntz, David; Toft, Søren

2011-01-01

The nutritional composition of prey is known to influence predator life histories, but how the life history strategies of predators affect their susceptibility to nutrient imbalance is less investigated. We used two wolf spider species with different life histories as model predators: Pardosa...... amentata, which have a fixed annual life cycle, and Pardosa prativaga, which reproduce later and can extend development across 2 years. We fed juvenile spiders of the two species ad libitum diets of one of six Drosophila melanogaster fly types varying in lipid:protein composition during three instars, from...

What parents want from doctors in end-of-life decision-making for children.

Science.gov (United States)

Sullivan, J; Monagle, P; Gillam, L

2014-03-01

End-of-life decision-making is difficult for everyone involved, as many studies have shown. Within this complexity, there has been little information on how parents see the role of doctors in end-of-life decision-making for children. This study aimed to examine parents' views and experiences of end-of-life decision-making. A qualitative method with a semistructured interview design was used. Parent participants were living in the community. Twenty-five bereaved parents. Parents reported varying roles taken by doctors: being the provider of information without opinion; giving information and advice as to the decision that should be taken; and seemingly being the decision maker for the child. The majority of parents found their child's doctor enabled them to be the ultimate decision maker for their child, which was what they very clearly wanted to be, and consequently enabled them to exercise their parental autonomy. Parents found it problematic when doctors took over decision-making. A less frequently reported, yet significant role for doctors was to affirm decisions after they had been made by parents. Other important aspects of the doctor's role were to provide follow-up support and referral. Understanding the role that doctors take in end-of-life decisions, and the subsequent impact of that role from the perspective of parents can form the basis of better informed clinical practice.

Masked expression of life-history traits in a highly variable environment

Science.gov (United States)

DeBoer, Jason A.; Fontaine, Joseph J.; Chizinski, Christopher J.; Pope, Kevin L.

2015-01-01

Differing life-history strategies may act as a constraint on reproductive expression that ultimately limits the ability of individual species to respond to changes in the magnitude or frequency of environmental variation, and potentially underlies the variation often inherent in phenotypic and evolved responses to anthropogenic change. Alternatively, if there are environmental cues that predict reproductive potential, differential expression of life-history strategies may represent differences in the adaptive capacity to optimize current reproductive value given variation in environmental conditions. We compared several aspects of walleye Sander vitreus spawning ecology at two reservoirs that differ in environmental variability (i.e., annual water-level fluctuation) to identify the capacity of phenotypic expression and the corresponding association with age. Despite significant differences in female body and liver masses between reservoirs that differ in environmental variability, we found no difference in reproductive investment measured by egg size and fecundity. Walleye in a highly variable environment appear to exhibit reproductive traits more typical of a short-lived life-history strategy, which may be resultant from the interaction of environmental and anthropogenic pressures. This finding emphasizes the need to identify the degree to which life-history expression represents physiological constraints versus ecological optimization, particularly as anthropogenic change continues to alter environmental conditions. 

Life History Trade-Offs Modulate the Speed of Senescence

DEFF Research Database (Denmark)

Salguero-Gómez, Roberto; Jones, Owen

2017-01-01

that the speed of senescence varies dramatically across the Tree of Life and that it has a moderate phylogenetic signal when considering both plants and animals but that this signal is stronger in animals than in plants, indicating that the strength of selection on the trait may differ between kingdoms. We next...... examined the speed of senescence at two taxonomic levels: comparing kingdoms, with plants more likely to postpone senescence than animals, and, when the data allowed for it, comparing taxonomic classes, where we found that pine trees are particularly slow to senesce, followed by reptiles and sponges. Most...... puzzling and worthy of investigation in itself. We used two open-data repositories of high-quality demographic information for animals and plants to present a novel overview of the degree of variation in life-history strategies and their component life-history traits, including the speed of senescence...

END-OF-LIFE DECISIONS IN DUTCH NEONATOLOGY

NARCIS (Netherlands)

Moratti, Sofia

2010-01-01

This contribution describes the regulation of end-of-life decisions in neonatology in the Netherlands. An account is given of the process of formulating rules, which includes a report by the Dutch Association for Paediatrics, two Court rulings, a report by a Consultation Group appointed by the

Biologic History and the Cardinal Rule of Life

Science.gov (United States)

Schopf, J. W.

2004-12-01

In broad perspective, the history of life is remarkably static -- once set, a system that has changed little over all of geological time. The basic chemistry of living systems (CHONSP, and the monomers and polymers they compose), the genetics and cellular structure of life, even the ecologic division of the biologic world into "eaters" (heterotrophs) and "eatees" (autotrophs), are innovations all dating from the Archean that have carried over to the present. Throughout Earth history, biology has followed the Cardinal Rule of Life -- avoid change, never evolve at all! Biology maintains the status quo, opportunistically responding only if conditions change. Life's credo might well be "if it ain't broken, don't fix it." Of course, biomolecules do get "broken," by mutations, but living systems have many biochemical repair mechanisms. Evolution is a result of small changes that slip through unfixed. We see the results of evolution in the fossil record only because of the vastness, the true enormity, of geological time. What events punctuated this static underpinning to produce the modern living world? Only three, each in its own way shaping the course of life's history. The earliest, photosynthesis, freed life from dependence on foodstuffs made by nonbiologic processes. The advent of the advanced form of this process, oxygenic ("green plant") photosynthesis -- also an Archean innovation -- pumped oxygen into the environment (markedly increasing energy yields), "rusted the Earth" (evidenced by banded iron-formations), and, by ˜2,300 Ma ago, led to establishment of an aerobic-anaerobic ecosystem like that today. Not surprisingly, given the Cardinal Rule of Life, the inventors of this innovation, microbial cyanobacteria, evolved little over billions of years. The second major innovation was sex. In the modern world, this reproductive process is exhibited only by nucleated (eukaryotic) cells, derived from non-sexual eukaryotic ancestors. Although eukaryotes date from ˜2

Life course experiences and lay diagnosis explain low-income parents' child dental decisions: a qualitative study.

Science.gov (United States)

Muirhead, Vanessa; Levine, Alissa; Nicolau, Belinda; Landry, Anne; Bedos, Christophe

2013-02-01

This study aimed to better understand low-income parents' child dental care decisions through a life course approach that captured parents' experiences within the social context of poverty. We conducted 43 qualitative life history interviews with 10 parents, who were long-term social assistance recipients living in Montreal, Canada. Thematic analysis involved interview debriefing, transcript coding, theme identification and data interpretation. Our interviews identified two emergent themes: lay diagnosis and parental oral health management. Parents described a process of 'lay diagnosis' that consisted of examining their children's teeth and interpreting their children's oral signs and symptoms based on their observations. These lay diagnoses were also shaped by their own dental crises, care experiences and oral health knowledge gained across a life course of poverty and dental disadvantage. Parents' management strategies included monitoring and managing their children's oral health themselves or by seeking professional recourse. Parents' management strategies were influenced both by their lay diagnoses and their perceived ability to manage their children's oral health. Parents felt responsible for their children's dental care, empowered to manage their oral health and sometimes forgo dental visits for their children because of their own self-management life history. This original approach revealed insights that help to understand why low-income parents may underutilize free dental services. Further research should consider how dental programs can nurture parental empowerment and capitalize on parents' perceived ability to diagnose and manage their children's oral health.

Life-history evolution and the microevolution of intermediary metabolism: activities of lipid-metabolizing enzymes in life-history morphs of a wing-dimorphic cricket.

Science.gov (United States)

Zera, Anthony J; Zhao, Zhangwu

2003-03-01

Although a considerable amount of information is available on the ecology, genetics, and physiology of life-history traits, much more limited data are available on the biochemical and genetic correlates of life-history variation within species. Specific activities of five enzymes of lipid biosynthesis and two enzymes of amino acid catabolism were compared among lines selected for flight-capable (LW[f]) versus flightless (SW) morphs of the cricket Gryllus firmus. These morphs, which exist in natural populations, differ genetically in ovarian growth (100-400% higher in SW) and aspects of flight capability including the size of wings and flight muscles, and the concentration of triglyceride flight fuel (40% greater in LW[f]). Consistently higher activity of each enzyme in LW(f) versus SW-selected lines, and strong co-segregation between morph and enzyme activity, demonstrated genetically based co-variance between wing morph and enzyme activity. Developmental profiles of enzyme activities strongly paralleled profiles of triglyceride accumulation during adulthood and previous measures of in vivo lipid biosynthesis. These data strongly imply that genetically based elevation in activities of lipogenic enzymes, and enzymes controlling the conversion of amino acids into lipids, is an important cause underlying the elevated accumulation of triglyceride in the LW(f) morph, a key biochemical component of the trade-off between elevated early fecundity and flight capability. Global changes in lipid and amino-acid metabolism appear to have resulted from microevolutionary alteration of regulators of metabolism. Finally, strong genotype x environment (diet) interactions were observed for most enzyme activities. Future progress in understanding the functional causes of life-history evolution requires a more detailed synthesis of the fields of life-history evolution and metabolic biochemistry. Wing polymorphism is a powerful experimental model in such integrative studies.

Seed after-ripening and dormancy determine adult life history independently of germination timing.

Science.gov (United States)

de Casas, Rafael Rubio; Kovach, Katherine; Dittmar, Emily; Barua, Deepak; Barco, Brenden; Donohue, Kathleen

2012-05-01

• Seed dormancy can affect life history through its effects on germination time. Here, we investigate its influence on life history beyond the timing of germination. • We used the response of Arabidopsis thaliana to chilling at the germination and flowering stages to test the following: how seed dormancy affects germination responses to the environment; whether variation in dormancy affects adult phenology independently of germination time; and whether environmental cues experienced by dormant seeds have an effect on adult life history. • Dormancy conditioned the germination response to low temperatures, such that prolonged periods of chilling induced dormancy in nondormant seeds, but stimulated germination in dormant seeds. The alleviation of dormancy through after-ripening was associated with earlier flowering, independent of germination date. Experimental dormancy manipulations showed that prolonged chilling at the seed stage always induced earlier flowering, regardless of seed dormancy. Surprisingly, this effect of seed chilling on flowering time was observed even when low temperatures did not induce germination. • In summary, seed dormancy influences flowering time and hence life history independent of its effects on germination timing. We conclude that the seed stage has a pronounced effect on life history, the influence of which goes well beyond the timing of germination. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

Functional Linkages for the Pace of Life, Life-history, and Environment in Birds

OpenAIRE

Williams, Joseph B.; Miller, Richard A.; Harper, James M.; Wiersma, Popko

2010-01-01

For vertebrates, body mass underlies much of the variation in metabolism, but among animals of the same body mass, metabolism varies six-fold. Understanding how natural selection can influence variation in metabolism remains a central focus of Physiological Ecologists. Life-history theory postulates that many physiological traits, such as metabolism, may be understood in terms of key maturational and reproductive characteristics over an organism’s life-span. Although it is widely acknowledged...

Experiences and attitudes towards end-of-life decisions amongst Danish physicians

DEFF Research Database (Denmark)

Folker, Anna Paldam; Holtug, Nils; Jensen, Annette B

1996-01-01

In this survey we have investigated the experiences and attitudes of Danish physicians regarding end-of-life decisions. Most respondents have made decisions that involve hastening the death of a patient, and almost all find it acceptable to do so. Such decisions are made more often, and considered...

Life history variation in Barents Sea fish: implications for sensitivity to fishing in a changing environment.

Science.gov (United States)

Wiedmann, Magnus A; Primicerio, Raul; Dolgov, Andrey; Ottesen, Camilla A M; Aschan, Michaela

2014-09-01

Under exploitation and environmental change, it is essential to assess the sensitivity and vulnerability of marine ecosystems to such stress. A species' response to stress depends on its life history. Sensitivity to harvesting is related to the life history "fast-slow" continuum, where "slow" species (i.e., large, long lived, and late maturing) are expected to be more sensitive to fishing than "fast" ones. We analyze life history traits variation for all common fish species in the Barents Sea and rank fishes along fast-slow gradients obtained by ordination analyses. In addition, we integrate species' fast-slow ranks with ecosystem survey data for the period 2004-2009, to assess life history variation at the community level in space and time. Arctic fishes were smaller, had shorter life spans, earlier maturation, larger offspring, and lower fecundity than boreal ones. Arctic fishes could thus be considered faster than the boreal species, even when body size was corrected for. Phylogenetically related species possessed similar life histories. Early in the study period, we found a strong spatial gradient, where members of fish assemblages in the southwestern Barents Sea displayed slower life histories than in the northeast. However, in later, warmer years, the gradient weakened caused by a northward movement of boreal species. As a consequence, the northeast experienced increasing proportions of slower fish species. This study is a step toward integrating life history traits in ecosystem-based areal management. On the basis of life history traits, we assess the fish sensitivity to fishing, at the species and community level. We show that climate warming promotes a borealization of fish assemblages in the northeast, associated with slower life histories in that area. The biology of Arctic species is still poorly known, and boreal species that now establish in the Arctic are fishery sensitive, which calls for cautious ecosystem management of these areas.

How Metamorphosis Is Different in Plethodontids: Larval Life History Perspectives on Life-Cycle Evolution

Science.gov (United States)

Beachy, Christopher K.; Ryan, Travis J.; Bonett, Ronald M.

2017-01-01

Plethodontid salamanders exhibit biphasic, larval form paedomorphic, and direct developing life cycles. This diversity of developmental strategies exceeds that of any other family of terrestrial vertebrate. Here we compare patterns of larval development among the three divergent lineages of biphasic plethodontids and other salamanders. We discuss how patterns of life-cycle evolution and larval ecology might have produced a wide array of larval life histories. Compared with many other salamanders, most larval plethodontids have relatively slow growth rates and sometimes exceptionally long larval periods (up to 60 mo). Recent phylogenetic analyses of life-cycle evolution indicate that ancestral plethodontids were likely direct developers. If true, then biphasic and paedomorphic lineages might have been independently derived through different developmental mechanisms. Furthermore, biphasic plethodontids largely colonized stream habitats, which tend to have lower productivity than seasonally ephemeral ponds. Consistent with this, plethodontid larvae grow very slowly, and metamorphic timing does not appear to be strongly affected by growth history. On the basis of this, we speculate that feeding schedules and stress hormones might play a comparatively reduced role in governing the timing of metamorphosis of stream-dwelling salamanders, particularly plethodontids. PMID:29269959

Life stress and family history for depression: the moderating role of past depressive episodes.

Science.gov (United States)

Monroe, Scott M; Slavich, George M; Gotlib, Ian H

2014-02-01

Three of the most consistently reported and powerful predictors of depression are a recent major life event, a positive family history for depression, and a personal history of past depressive episodes. Little research, however, has evaluated the inter-relations among these predictors in depressed samples. Such information is descriptively valuable and potentially etiologically informative. In the present article we summarize the existing literature and test four predictions in a sample of 62 clinically depressed individuals: (1) participants who experienced a major life event prior to onset would be less likely than participants who did not experience a major life event to have a positive family history for depression; (2) participants with a recent major life event would have fewer lifetime episodes of depression than would participants without; (3) participants with a positive family history for depression would have more lifetime episodes of depression than would participants with a negative family history for depression; and (4) we would obtain a 3-way interaction in which participants with a positive family history and without a major life event would have the most lifetime episodes, whereas participants with a negative family history and a major life event would have the fewest lifetime episodes. The first three predictions were confirmed, and the fourth prediction partially confirmed. These novel findings begin to elucidate the complex relations among these three prominent risk factors for depression, and point to avenues of research that may help illuminate the origins of depressive episodes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Functional linkages for the pace of life, life-history, and environment in birds.

Science.gov (United States)

Williams, Joseph B; Miller, Richard A; Harper, James M; Wiersma, Popko

2010-11-01

For vertebrates, body mass underlies much of the variation in metabolism, but among animals of the same body mass, metabolism varies six-fold. Understanding how natural selection can influence variation in metabolism remains a central focus of Physiological Ecologists. Life-history theory postulates that many physiological traits, such as metabolism, may be understood in terms of key maturational and reproductive characteristics over an organism's life-span. Although it is widely acknowledged that physiological processes serve as a foundation for life-history trade-offs, the physiological mechanisms that underlie the diversification of life-histories remain elusive. Data show that tropical birds have a reduced basal metabolism (BMR), field metabolic rate, and peak metabolic rate compared with temperate counterparts, results consistent with the idea that a low mortality, and therefore increased longevity, and low productivity is associated with low mass-specific metabolic rate. Mass-adjusted BMR of tropical and temperate birds was associated with survival rate, in accordance with the view that animals with a slow pace of life tend to have increased life spans. To understand the mechanisms responsible for a reduced rate of metabolism in tropical birds compared with temperate species, we summarized an unpublished study, based on data from the literature, on organ masses for both groups. Tropical birds had smaller hearts, kidneys, livers, and pectoral muscles than did temperate species of the same body size, but they had a relatively larger skeletal mass. Direct measurements of organ masses for tropical and temperate birds showed that the heart, kidneys, and lungs were significantly smaller in tropical birds, although sample sizes were small. Also from an ongoing study, we summarized results to date on connections between whole-organism metabolism in tropical and temperate birds and attributes of their dermal fibroblasts grown in cell culture. Cells derived from

Communication and Decision-Making About End-of-Life Care in the Intensive Care Unit.

Science.gov (United States)

Brooks, Laura Anne; Manias, Elizabeth; Nicholson, Patricia

2017-07-01

Clinicians in the intensive care unit commonly face decisions involving withholding or withdrawing life-sustaining therapy, which present many clinical and ethical challenges. Communication and shared decision-making are key aspects relating to the transition from active treatment to end-of-life care. To explore the experiences and perspectives of nurses and physicians when initiating end-of-life care in the intensive care unit. The study was conducted in a 24-bed intensive care unit in Melbourne, Australia. An interpretative, qualitative inquiry was used, with focus groups as the data collection method. Intensive care nurses and physicians were recruited to participate in a discipline-specific focus group. Focus group discussions were audio-recorded, transcribed, and subjected to thematic data analysis. Five focus groups were conducted; 17 nurses and 11 physicians participated. The key aspects discussed included communication and shared decision-making. Themes related to communication included the timing of end-of-life care discussions and conducting difficult conversations. Implementation and multidisciplinary acceptance of end-of-life care plans and collaborative decisions involving patients and families were themes related to shared decision-making. Effective communication and decision-making practices regarding initiating end-of-life care in the intensive care unit are important. Multidisciplinary implementation and acceptance of end-of-life care plans in the intensive care unit need improvement. Clear organizational processes that support the introduction of nurse and physician end-of-life care leaders are essential to optimize outcomes for patients, family members, and clinicians. ©2017 American Association of Critical-Care Nurses.

Primate enamel evinces long period biological timing and regulation of life history.

Science.gov (United States)

Bromage, Timothy G; Hogg, Russell T; Lacruz, Rodrigo S; Hou, Chen

2012-07-21

The factor(s) regulating the combination of traits that define the overall life history matrix of mammalian species, comprising attributes such as brain and body weight, age at sexual maturity, lifespan and others, remains a complete mystery. The principal objectives of the present research are (1) to provide evidence for a key variable effecting life history integration and (2) to provide a model for how one would go about investigating the metabolic mechanisms responsible for this rhythm. We suggest here that a biological rhythm with a period greater than the circadian rhythm is responsible for observed variation in primate life history. Evidence for this rhythm derives from studies of tooth enamel formation. Enamel contains an enigmatic periodicity in its microstructure called the striae of Retzius, which develops at species specific intervals in units of whole days. We refer to this enamel rhythm as the repeat interval (RI). For primates, we identify statistically significant relationships between RI and all common life history traits. Importantly, RI also correlates with basal and specific metabolic rates. With the exception of estrous cyclicity, all relationships share a dependence upon body mass. This dependence on body mass informs us that some aspect of metabolism is responsible for periodic energy allocations at RI timescales, regulating cell proliferation rates and growth, thus controlling the pace, patterning, and co-variation of life history traits. Estrous cyclicity relates to the long period rhythm in a body mass-independent manner. The mass-dependency and -independency of life history relationships with RI periodicity align with hypothalamic-mediated neurosecretory anterior and posterior pituitary outputs. We term this period the Havers-Halberg Oscillation (HHO), in reference to Clopton Havers, a 17th Century hard tissue anatomist, and Franz Halberg, a long-time explorer of long-period rhythms. We propose a mathematical model that may help elucidate

Caring Decisions: The Development of a Written Resource for Parents Facing End-of-Life Decisions.

Science.gov (United States)

Xafis, Vicki; Gillam, Lynn; Hynson, Jenny; Sullivan, Jane; Cossich, Mary; Wilkinson, Dominic

2015-11-01

Written resources in adult intensive care have been shown to benefit families facing end of life (EoL) decisions. There are few resources for parents making EoL decisions for their child and no existing resources addressing ethical issues. The Caring Decisions handbook and website were developed to fill these gaps. We discuss the development of the resources, modification after reviewer feedback and findings from initial pilot implementation. A targeted literature review-to identify resources and factors that impact on parental EoL decision-making; development phase-guided by the literature and the researchers' expertise; consultation process-comprised a multi-disciplinary panel of experts and parents; pilot evaluation study-hard-copy handbook was distributed as part of routine care at an Australian Children's Hospital. Twelve experts and parents formed the consultation panel. Eight parents of children with life-limiting conditions and clinicians were interviewed in the pilot study. Numerous factors supporting/impeding EoL decisions were identified. Caring Decisions addressed issues identified in the literature and by the multidisciplinary research team. The consultation panel provided overwhelmingly positive feedback. Pilot study parents found the resources helpful and comforting. Most clinicians viewed the resources as very beneficial to parents and identified them as ideal for training purposes. The development of the resources addressed many of the gaps in existing resources. The consultation process and the pilot study suggest these resources could be of significant benefit to parents and clinicians.

Team Leadership and Cancer End-of-Life Decision Making.

Science.gov (United States)

Waldfogel, Julie M; Battle, Dena J; Rosen, Michael; Knight, Louise; Saiki, Catherine B; Nesbit, Suzanne A; Cooper, Rhonda S; Browner, Ilene S; Hoofring, Laura H; Billing, Lynn S; Dy, Sydney M

2016-11-01

End-of-life decision making in cancer can be a complicated process. Patients and families encounter multiple providers throughout their cancer care. When the efforts of these providers are not well coordinated in teams, opportunities for high-quality, longitudinal goals of care discussions can be missed. This article reviews the case of a 55-year-old man with lung cancer, illustrating the barriers and missed opportunities for end-of-life decision making in his care through the lens of team leadership, a key principle in the science of teams. The challenges demonstrated in this case reflect the importance of the four functions of team leadership: information search and structuring, information use in problem solving, managing personnel resources, and managing material resources. Engaging in shared leadership of these four functions can help care providers improve their interactions with patients and families concerning end-of-life care decision making. This shared leadership can also produce a cohesive care plan that benefits from the expertise of the range of available providers while reflecting patient needs and preferences. Clinicians and researchers should consider the roles of team leadership functions and shared leadership in improving patient care when developing and studying models of cancer care delivery.

The life-history of a springtail Folsomia candida living in soil contaminated with nonylphenol

DEFF Research Database (Denmark)

Widarto, T. H.; Krogh, P. H.; Forbes, V.

Nonylphenol (NP) has been known for long time as a suspected endocrine disruptor in animals. We have conducted an experiment to look at the effect of NP on the life-history of the parthenogenetic springtail, Folsomia candida. Six sub-lethal concentrations (0, 8,16, 24, 32, 40 mg/kg dry soil......) were applied to 6 replicates of soil containing an individual of 0-1 day old juvenile. During continuous exposure (63 days), we assessed springtail life-history traits such as: survival, growth rate, molting time, time between molting, time to first reproduction, egg production, and viability...... population growth rate (l). Decomposition analysis to investigate the contribution of each of the affected life-history traits to the effects observed on l, and elasticity analysis to examine the relative sensitivity of l to changes in each of the life history traits provided valuable insight...

End-of-life decision-making for children with severe developmental disabilities: The parental perspective.

Science.gov (United States)

Zaal-Schuller, I H; de Vos, M A; Ewals, F V P M; van Goudoever, J B; Willems, D L

2016-01-01

The objectives of this integrative review were to understand how parents of children with severe developmental disorders experience their involvement in end-of-life decision-making, how they prefer to be involved and what factors influence their decisions. We searched MEDLINE, EMBASE, CINAHL and PsycINFO. The search was limited to articles in English or Dutch published between January 2004 and August 2014. We included qualitative and quantitative original studies that directly investigated the experiences of parents of children aged 0-18 years with severe developmental disorders for whom an end-of-life decision had been considered or made. We identified nine studies that met all inclusion criteria. Reportedly, parental involvement in end-of-life decision-making varied widely, ranging from having no involvement to being the sole decision-maker. Most parents preferred to actively share in the decision-making process regardless of their child's specific diagnosis or comorbidity. The main factors that influenced parents in their decision-making were: their strong urge to advocate for their child's best interests and to make the best (possible) decision. In addition, parents felt influenced by their child's visible suffering, remaining quality of life and the will they perceived in their child to survive. Most parents of children with severe developmental disorders wish to actively share in the end-of-life decision-making process. An important emerging factor in this process is the parents' feeling that they have to stand up for their child's interests in conversations with the medical team. Copyright © 2015 Elsevier Ltd. All rights reserved.

Family Communication about End-of-Life Decisions and the Enactment of the Decision-Maker Role

Directory of Open Access Journals (Sweden)

April R. Trees

2017-06-01

Full Text Available End-of-life (EOL decisions in families are complex and emotional sites of family interaction necessitating family members coordinate roles in the EOL decision-making process. How family members in the United States enact the decision-maker role in EOL decision situations was examined through in-depth interviews with 22 individuals who participated in EOL decision-making for a family member. A number of themes emerged from the data with regard to the enactment of the decision-maker role. Families varied in how decision makers enacted the role in relation to collective family input, with consulting, informing and collaborating as different patterns of behavior. Formal family roles along with gender- and age-based roles shaped who took on the decision-maker role. Additionally, both family members and medical professionals facilitated or undermined the decision-maker’s role enactment. Understanding the structure and enactment of the decision-maker role in family interaction provides insight into how individuals and/or family members perform the decision-making role within a cultural context that values autonomy and self-determination in combination with collective family action in EOL decision-making.

Theories of Health Care Decision Making at the End of Life: A Meta-Ethnography.

Science.gov (United States)

Kim, Kyounghae; Heinze, Katherine; Xu, Jiayun; Kurtz, Melissa; Park, Hyunjeong; Foradori, Megan; Nolan, Marie T

2017-08-01

The aim of this meta-ethnography is to appraise the types and uses of theories relative to end-of-life decision making and to develop a conceptual framework to describe end-of-life decision making among patients with advanced cancers, heart failure, and amyotrophic lateral sclerosis (ALS) and their caregivers or providers. We used PubMed, Embase, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases to extract English-language articles published between January 2002 and April 2015. Forty-three articles were included. The most common theories included decision-making models ( n = 14) followed by family-centered ( n = 11) and behavioral change models ( n = 7). A conceptual framework was developed using themes including context of decision making, communication and negotiation of decision making, characteristics of decision makers, goals of decision making, options and alternatives, and outcomes. Future research should enhance and apply these theories to guide research to develop patient-centered decision-making programs that facilitate informed and shared decision making at the end of life among patients with advanced illness and their caregivers.

Height among Women is Curvilinearly Related to Life History Strategy

Directory of Open Access Journals (Sweden)

Abraham P. Buunk

2009-10-01

Full Text Available It was hypothesized that women of medium height would show a more secure, long-term mating pattern characterized by less jealousy, less intrasexual competition and a “slower” life history strategy. In three samples of female undergraduate students clear support was found for these hypotheses. In Study 1, among 120 participants, height was curvilinearly related to well-established measures of possessive and reactive jealousy, with women of medium height being less jealous than tall as well as short women. In Study 2, among 40 participants, height was curvilinearly related to intrasexual competition, with women of medium height being less competitive towards other women than tall as well as short women. In Study 3, among 299 participants, height was curvilinearly related to the Mini-K, a well-validated measure of “slower” life history strategy, with women of medium height having a slower life history strategy than tall as well as short women. The results suggest that women of medium height tend to follow a different mating strategy than either tall or short women. Various explanations and implications of these results are discussed.

Immune defense and host life history.

Science.gov (United States)

Zuk, Marlene; Stoehr, Andrew M

2002-10-01

Recent interest has focused on immune response in an evolutionary context, with particular attention to disease resistance as a life-history trait, subject to trade-offs against other traits such as reproductive effort. Immune defense has several characteristics that complicate this approach, however; for example, because of the risk of autoimmunity, optimal immune defense is not necessarily maximum immune defense. Two important types of cost associated with immunity in the context of life history are resource costs, those related to the allocation of essential but limited resources, such as energy or nutrients, and option costs, those paid not in the currency of resources but in functional or structural components of the organism. Resource and option costs are likely to apply to different aspects of resistance. Recent investigations into possible trade-offs between reproductive effort, particularly sexual displays, and immunity have suggested interesting functional links between the two. Although all organisms balance the costs of immune defense against the requirements of reproduction, this balance works out differently for males than it does for females, creating sex differences in immune response that in turn are related to ecological factors such as the mating system. We conclude that immune response is indeed costly and that future work would do well to include invertebrates, which have sometimes been neglected in studies of the ecology of immune defense.

"Ant" and "grasshopper" life-history strategies in Saccharomyces cerevisiae.

Science.gov (United States)

Spor, Aymé; Wang, Shaoxiao; Dillmann, Christine; de Vienne, Dominique; Sicard, Delphine

2008-02-13

From the evolutionary and ecological points of view, it is essential to distinguish between the genetic and environmental components of the variability of life-history traits and of their trade-offs. Among the factors affecting this variability, the resource uptake rate deserves particular attention, because it depends on both the environment and the genetic background of the individuals. In order to unravel the bases of the life-history strategies in yeast, we grew a collection of twelve strains of Saccharomyces cerevisiae from different industrial and geographical origins in three culture media differing for their glucose content. Using a population dynamics model to fit the change of population size over time, we estimated the intrinsic growth rate (r), the carrying capacity (K), the mean cell size and the glucose consumption rate per cell. The life-history traits, as well as the glucose consumption rate, displayed large genetic and plastic variability and genetic-by-environment interactions. Within each medium, growth rate and carrying capacity were not correlated, but a marked trade-off between these traits was observed over the media, with high K and low r in the glucose rich medium and low K and high r in the other media. The cell size was tightly negatively correlated to carrying capacity in all conditions. The resource consumption rate appeared to be a clear-cut determinant of both the carrying capacity and the cell size in all media, since it accounted for 37% to 84% of the variation of those traits. In a given medium, the strains that consume glucose at high rate have large cell size and low carrying capacity, while the strains that consume glucose at low rate have small cell size but high carrying capacity. These two contrasted behaviors may be metaphorically defined as "ant" and "grasshopper" strategies of resource utilization. Interestingly, a strain may be "ant" in one medium and "grasshopper" in another. These life-history strategies are discussed

"Ant" and "grasshopper" life-history strategies in Saccharomyces cerevisiae.

Directory of Open Access Journals (Sweden)

Aymé Spor

Full Text Available From the evolutionary and ecological points of view, it is essential to distinguish between the genetic and environmental components of the variability of life-history traits and of their trade-offs. Among the factors affecting this variability, the resource uptake rate deserves particular attention, because it depends on both the environment and the genetic background of the individuals. In order to unravel the bases of the life-history strategies in yeast, we grew a collection of twelve strains of Saccharomyces cerevisiae from different industrial and geographical origins in three culture media differing for their glucose content. Using a population dynamics model to fit the change of population size over time, we estimated the intrinsic growth rate (r, the carrying capacity (K, the mean cell size and the glucose consumption rate per cell. The life-history traits, as well as the glucose consumption rate, displayed large genetic and plastic variability and genetic-by-environment interactions. Within each medium, growth rate and carrying capacity were not correlated, but a marked trade-off between these traits was observed over the media, with high K and low r in the glucose rich medium and low K and high r in the other media. The cell size was tightly negatively correlated to carrying capacity in all conditions. The resource consumption rate appeared to be a clear-cut determinant of both the carrying capacity and the cell size in all media, since it accounted for 37% to 84% of the variation of those traits. In a given medium, the strains that consume glucose at high rate have large cell size and low carrying capacity, while the strains that consume glucose at low rate have small cell size but high carrying capacity. These two contrasted behaviors may be metaphorically defined as "ant" and "grasshopper" strategies of resource utilization. Interestingly, a strain may be "ant" in one medium and "grasshopper" in another. These life-history

Towards cancer-aware life-history modelling

OpenAIRE

Kokko, Hanna; Hochberg, Michael

2015-01-01

Studies of body size evolution, and life-history theory in general, are conducted without taking into account cancer as a factor that can end an organism’s reproductive lifespan. This reflects a tacit assumption that predation, parasitism and starvation are of overriding importance in the wild. We argue here that even if deaths directly attributable to cancer are a rarity in studies of natural populations, it remains incorrect to infer that cancer has not been of importance in shaping observe...

Geographic, genetic and life-history variability in a sex-changing fish

Directory of Open Access Journals (Sweden)

Chiara Benvenuto

2015-11-01

Full Text Available Sequential hermaphroditism, commonly referred to as sex change or sex reversal, is a striking phenomenon in mating-system evolution and the most remarkable example of sexual plasticity. Among vertebrates, it is specific to teleosts. Some fish species reproduce initially as females and then change into males (protogynous hermaphrodites or vice versa (protandrous hermaphrodites. The white sea bream, Diplodus sargus, exhibits a high degree of sexual plasticity: populations have been reported to be gonochoristic, protandrous or digynic (with primary females, derived from intersexual juveniles, and secondary females, derived from males. We analysed populations collected from eight different locations across the species distribution range (between the Mediterranean and the North-Eastern Atlantic. These populations are characterized by different degrees of connectivity, spatial demographics and life histories. Using individual-based analyses, we linked the genetic structure of each specimen with environmental heterogeneity, life-history traits and reproductive modes. Our aim is to gather a better understanding of the variation in reproductive life-history strategies in this sexually plastic species. Diplodus sargus is a valuable candidate organism to investigate sequential hermaphroditism and it also has a commercial value. The application of population genetics tools against the background of life-history theory can bring valuable insights for the management of marine resources. The geographical patterns of sex change (and of age- and size-at-sex change linked with population genetics can be pivotal for both theoretical investigations and conservation and management plans in marine areas.

Ethics of End of Life Decisions in Pediatrics: A Narrative Review of the Roles of Caregivers, Shared Decision-Making, and Patient Centered Values

Directory of Open Access Journals (Sweden)

Jonathan D. Santoro

2018-04-01

Full Text Available Background: This manuscript reviews unique aspects of end of life decision-making in pediatrics. Methods: A narrative literature review of pediatric end of life issues was performed in the English language. Results: While a paternalistic approach is typically applied to children with life-limiting medical prognoses, the cognitive, language, and physical variability in this patient population is wide and worthy of review. In end of life discussions in pediatrics, the consideration of a child’s input is often not reviewed in depth, although a shared decision-making model is ideal for use, even for children with presumed limitations due to age. This narrative review of end of life decision-making in pediatric care explores nomenclature, the introduction of the concept of death, relevant historical studies, limitations to the shared decision-making model, the current state of end of life autonomy in pediatrics, and future directions and needs. Although progress is being made toward a more uniform and standardized approach to care, few non-institutional protocols exist. Complicating factors in the lack of guidelines include the unique facets of pediatric end of life care, including physical age, paternalism, the cognitive and language capacity of patients, subconscious influencers of parents, and normative values of death in pediatrics. Conclusions: Although there have been strides in end of life decision-making in pediatrics, further investigation and research is needed in this field.

Ethics of End of Life Decisions in Pediatrics: A Narrative Review of the Roles of Caregivers, Shared Decision-Making, and Patient Centered Values.

Science.gov (United States)

Santoro, Jonathan D; Bennett, Mariko

2018-04-26

Background: This manuscript reviews unique aspects of end of life decision-making in pediatrics. Methods: A narrative literature review of pediatric end of life issues was performed in the English language. Results: While a paternalistic approach is typically applied to children with life-limiting medical prognoses, the cognitive, language, and physical variability in this patient population is wide and worthy of review. In end of life discussions in pediatrics, the consideration of a child’s input is often not reviewed in depth, although a shared decision-making model is ideal for use, even for children with presumed limitations due to age. This narrative review of end of life decision-making in pediatric care explores nomenclature, the introduction of the concept of death, relevant historical studies, limitations to the shared decision-making model, the current state of end of life autonomy in pediatrics, and future directions and needs. Although progress is being made toward a more uniform and standardized approach to care, few non-institutional protocols exist. Complicating factors in the lack of guidelines include the unique facets of pediatric end of life care, including physical age, paternalism, the cognitive and language capacity of patients, subconscious influencers of parents, and normative values of death in pediatrics. Conclusions: Although there have been strides in end of life decision-making in pediatrics, further investigation and research is needed in this field.

Decision support for life extension of technical systems through virtual age modelling

International Nuclear Information System (INIS)

Pérez Ramírez, Pedro A.; Utne, Ingrid Bouwer

2013-01-01

This article presents a virtual age model for decision support regarding life extension of ageing repairable systems. The aim of the model is to evaluate different life extension decision alternatives and their impact on the future performance of the system. The model can be applied to systems operated continuously (e.g., process systems) and systems operated on demand (e.g., safety systems). Deterioration and efficiency of imperfect maintenance is assessed when there is limited or no degradation data, and only failure and maintenance data is available. Systems that are in operation can be studied, meaning that the systems may be degraded. The current degradation is represented by a “current virtual age”, which is calculated from recorded maintenance data. The model parameters are estimated with the maximum likelihood method. A case study illustrates the application of the model for life extension of two fire water pumps in an oil and gas facility. The performance of the pump system is assessed with respect to number of failures, safety unavailability and costs during the life extension period. -- Highlights: ► Life extension assessment of technical systems using virtual age model is proposed. ► A virtual age model is generalised for systems in stand-by and continuous operation. ► The concept of current virtual age describes technical condition of the system. ► Different decision alternatives for life extension can be easily analysed. ► The decision process is improved even when only scarce failure data is available

The Effect of Providing Life Support on Nurses' Decision Making Regarding Life Support for Themselves and Family Members in Japan.

Science.gov (United States)

Shaku, Fumio; Tsutsumi, Madoka

2016-12-01

Decision making in terminal illness has recently received increased attention. In Japan, patients and their families typically make decisions without understanding either the severity of illness or the efficacy of life-supporting treatments at the end of life. Japanese culture traditionally directs the family to make decisions for the patient. This descriptive study examined the influence of the experiences of 391 Japanese nurses caring for dying patients and family members and how that experience changed their decision making for themselves and their family members. The results were mixed but generally supported the idea that the more experience nurses have in caring for the dying, the less likely they would choose to institute lifesupport measures for themselves and family members. The results have implications for discussions on end-of-life care. © The Author(s) 2016.

Mapping phenotypic plasticity and genotype-environment interactions affecting life-history traits in Caenorhabditis elegans

NARCIS (Netherlands)

Gutteling, E.W.; Riksen, J.A.G.; Bakker, J.; Kammenga, J.E.

2007-01-01

Phenotypic plasticity and genotype-environment interactions (GEI) play an important role in the evolution of life histories. Knowledge of the molecular genetic basis of plasticity and GEI provides insight into the underlying mechanisms of life-history changes in different environments. We used a

Swiss doctors' attitudes towards end-of-life decisions and their determinants: a comparison of three language regions.

Science.gov (United States)

Fischer, Susanne; Bosshard, Georg; Faisst, Karin; Tschopp, Alois; Fischer, Johannes; Bär, Walter; Gutzwiller, Felix

2006-06-10

To investigate attitudes to end-of-life decisions, and the influence of cultural factors and of doctors' personal characteristics on these attitudes. As part of a European research project (EURELD), a study on attitudes towards medical end-of-life decisions was conducted among doctors in the German-, French- and Italian-speaking areas of Switzerland. A written questionnaire was sent to a random sample of nine different types of specialist; it presented 14 statements on end-of-life decisions and doctors were asked whether they agreed or disagreed with them. The response rate was 64%. 1360 questionnaires were studied. The results show general agreement with statements on the alleviation of pain and other symptoms with possible life-shortening effect, as well as on non-treatment decisions. The language region was a strong determinant of agreement on some attitudes towards end-of-life decisions. Agreement on the use of lethal drugs and alleviation of pain and other symptoms with possible life-shortening effect was higher among French-speaking than among German- and Italian-speaking doctors. For nontreatment decisions, agreement was higher in the German-speaking region than in the French- and Italian-speaking regions of the country. Italian-speaking doctors were strongly opposed to any kind of end-of-life decision. Religious believers and those who attended a larger number of terminal patients tended to disagree more often with end-of-life decisions than the other doctors. In end-of-life decision-making, Switzerland represents "Europe in miniature". The impact on end-of-life decisions of cultural factors and the number of terminal patients attended needs further consideration.

Preferences for autonomy in end-of-life decision making in modern Korean society.

Science.gov (United States)

Kim, Su Hyun

2015-03-01

The demand for autonomy in medical decision making is increasing among Korean people, but it is not well known why some people prefer autonomy in decision making but others do not. The aim of this study was to determine the extent to which Korean adults wished to exercise autonomy in the process of decision making regarding end-of-life treatment and to determine whether economic issues and family functioning, in particular, were associated with preferences for participation in decision making in Korean people. This study was a cross-sectional correlational study using a survey. Data were collected using structured questionnaires from 354 patients or their families who visited ambulatory departments at two general hospitals in South Korea, recruited by the proportionate quota sampling method. Data analysis was performed using multinomial logistic regression analyses. The study was approved by the hospitals' directors and the ethics committee of Kyungpook National University Hospital. Written informed consent was given by all participants. A majority of Korean people wanted to make autonomous decisions regarding treatment at the end of life. Preferences for autonomous decision making regarding end-of-life treatment, rather than relying on family, showed a significant increase in association with poor family functioning and low income. Results of this study suggested the necessity for development of alternatives to a dominant traditional "family-centered" approach in Korean people, in order to enhance end-of-life decision making for people who wish to take an active role in the decision-making process. Healthcare providers need to examine not only patients' preferred decision-making style but also any reasons for their choice, in particular, family conflict and financial burden. © The Author(s) 2014.

Life history and bioeconomy of the house mouse.

Science.gov (United States)

Berry, R J; Bronson, F H

1992-11-01

1. More is known about the western European house mouse, Mus (musculus) domesticus than any other non-human mammal. If laboratory and field information is combined, an extremely valuable understanding of the species' bioeconomy could be obtained. 2. The seven stages of mouse life-history are surveyed (up to birth, nest life, sex life, social structure, population statics and stability, senescence, and death), and the interactions between the changing phenotype and the environment are described. 3. These interactions can be used to build up a model of the opportunities and compromises which result in the fitness of individual mice. It is not yet possible to quantify such a model, but this should in principle be achievable.

Diagnosing the dangerous demography of manta rays using life history theory

Directory of Open Access Journals (Sweden)

Nicholas K. Dulvy

2014-05-01

Full Text Available Background. The directed harvest and global trade in the gill plates of mantas, and devil rays, has led to increased fishing pressure and steep population declines in some locations. The slow life history, particularly of the manta rays, is cited as a key reason why such species have little capacity to withstand directed fisheries. Here, we place their life history and demography within the context of other sharks and rays.Methods. Despite the limited availability of data, we use life history theory and comparative analysis to estimate the intrinsic risk of extinction (as indexed by the maximum intrinsic rate of population increase rmax for a typical generic manta ray using a variant of the classic Euler–Lotka demographic model. This model requires only three traits to calculate the maximum intrinsic population growth rate rmax: von Bertalanffy growth rate, annual pup production and age at maturity. To account for the uncertainty in life history parameters, we created plausible parameter ranges and propagate these uncertainties through the model to calculate a distribution of the plausible range of rmax values.Results. The maximum population growth rate rmax of manta ray is most sensitive to the length of the reproductive cycle, and the median rmax of 0.116 year−1 95th percentile [0.089–0.139] is one of the lowest known of the 106 sharks and rays for which we have comparable demographic information.Discussion. In common with other unprotected, unmanaged, high-value large-bodied sharks and rays the combination of very low population growth rates of manta rays, combined with the high value of their gill rakers and the international nature of trade, is highly likely to lead to rapid depletion and potential local extinction unless a rapid conservation management response occurs worldwide. Furthermore, we show that it is possible to derive important insights into the demography extinction risk of data-poor species using well-established life

Diagnosing the dangerous demography of manta rays using life history theory.

Science.gov (United States)

Dulvy, Nicholas K; Pardo, Sebastián A; Simpfendorfer, Colin A; Carlson, John K

2014-01-01

Background. The directed harvest and global trade in the gill plates of mantas, and devil rays, has led to increased fishing pressure and steep population declines in some locations. The slow life history, particularly of the manta rays, is cited as a key reason why such species have little capacity to withstand directed fisheries. Here, we place their life history and demography within the context of other sharks and rays. Methods. Despite the limited availability of data, we use life history theory and comparative analysis to estimate the intrinsic risk of extinction (as indexed by the maximum intrinsic rate of population increase r max) for a typical generic manta ray using a variant of the classic Euler-Lotka demographic model. This model requires only three traits to calculate the maximum intrinsic population growth rate r max: von Bertalanffy growth rate, annual pup production and age at maturity. To account for the uncertainty in life history parameters, we created plausible parameter ranges and propagate these uncertainties through the model to calculate a distribution of the plausible range of r max values. Results. The maximum population growth rate r max of manta ray is most sensitive to the length of the reproductive cycle, and the median r max of 0.116 year(-1) 95th percentile [0.089-0.139] is one of the lowest known of the 106 sharks and rays for which we have comparable demographic information. Discussion. In common with other unprotected, unmanaged, high-value large-bodied sharks and rays the combination of very low population growth rates of manta rays, combined with the high value of their gill rakers and the international nature of trade, is highly likely to lead to rapid depletion and potential local extinction unless a rapid conservation management response occurs worldwide. Furthermore, we show that it is possible to derive important insights into the demography extinction risk of data-poor species using well-established life history theory.

The origin of parental care in relation to male and female life history.

Science.gov (United States)

Klug, Hope; Bonsall, Michael B; Alonzo, Suzanne H

2013-04-01

The evolution of maternal, paternal, and bi-parental care has been the focus of a great deal of research. Males and females vary in basic life-history characteristics (e.g., stage-specific mortality, maturation) in ways that are unrelated to parental investment. Surprisingly, few studies have examined the effect of this variation in male and female life history on the evolution of care. Here, we use a theoretical approach to determine the sex-specific life-history characteristics that give rise to the origin of paternal, maternal, or bi-parental care from an ancestral state of no care. Females initially invest more into each egg than males. Despite this inherent difference between the sexes, paternal, maternal, and bi-parental care are equally likely when males and females are otherwise similar. Thus, sex differences in initial zygotic investment do not explain the origin of one pattern of care over another. However, sex differences in adult mortality, egg maturation rate, and juvenile survival affect the pattern of care that will be most likely to evolve. Maternal care is more likely if female adult mortality is high, whereas paternal care is more likely if male adult mortality is high. These findings suggest that basic life-history differences between the sexes can alone explain the origin of maternal, paternal, and bi-parental care. As a result, the influence of life-history characteristics should be considered as a baseline scenario in studies examining the origin of care.

Early Life Histories of Fishes: New Developmental, Ecological and ...

African Journals Online (AJOL)

ontogeny and life history models revisited' which is an unabridged .... Hamburg, Germany, in August 1984. The papers are ..... Cambridge University Press, Cambridge, New York and ... lessons to be learnt from the well-illustrated keys and for.

Road–side herbaceous vegetation: life history groups and habitat preferences

Czech Academy of Sciences Publication Activity Database

Šerá, Božena

2010-01-01

Roč. 58, č. 1 (2010), s. 69-79 ISSN 1505-2249 R&D Projects: GA MŠk(CZ) OC 350.002 Institutional research plan: CEZ:AV0Z60870520 Keywords : road-side vegetation * road ecology * life form * life history * habitat preference * alien species Subject RIV: EH - Ecology, Behaviour Impact factor: 0.542, year: 2010

Variations in morphological and life-history traits under extreme ...

Indian Academy of Sciences (India)

Two extremely stressful temperatures (18°C and 32°C) and one standard ... and non-stressful environments on the morphological and life-history traits in males and ... Genetics Laboratory, Department of Zoology, Banaras Hindu University, ...

The Montreal Protocol treaty and its illuminating history of science-policy decision-making

Science.gov (United States)

Grady, C.

2017-12-01

The Montreal Protocol on Substances that Deplete the Ozone Layer, hailed as one of the most effective environmental treaties of all time, has a thirty year history of science-policy decision-making. The partnership between Parties to the Montreal Protocol and its technical assessment panels serve as a basis for understanding successes and evaluating stumbles of global environmental decision-making. Real-world environmental treaty negotiations can be highly time-sensitive, politically motivated, and resource constrained thus scientists and policymakers alike are often unable to confront the uncertainties associated with the multitude of choices. The science-policy relationship built within the framework of the Montreal Protocol has helped constrain uncertainty and inform policy decisions but has also highlighted the limitations of the use of scientific understanding in political decision-making. This talk will describe the evolution of the scientist-policymaker relationship over the history of the Montreal Protocol. Examples will illustrate how the Montreal Protocol's technical panels inform decisions of the country governments and will characterize different approaches pursued by different countries with a particular focus on the recently adopted Kigali Amendment. In addition, this talk will take a deeper dive with an analysis of the historic technical panel assessments on estimating financial resources necessary to enable compliance to the Montreal Protocol compared to the political financial decisions made through the Protocol's Multilateral Fund replenishment negotiation process. Finally, this talk will describe the useful lessons and challenges from these interactions and how they may be applicable in other environmental management frameworks across multiple scales under changing climatic conditions.

Local adaptation in brown trout early life-history traits: implications for climate change adaptability

DEFF Research Database (Denmark)

Jensen, L.F.; Hansen, Michael Møller; Pertoldi, C.

2008-01-01

to adapt. Temperature-related adaptability in traits related to phenology and early life history are expected to be particularly important in salmonid fishes. We focused on the latter and investigated whether four populations of brown trout (Salmo trutta) are locally adapted in early life-history traits...

Intersections of life histories and science identities: the stories of three preservice elementary teachers

Science.gov (United States)

Avraamidou, Lucy

2016-03-01

Grounded within Connelly and Clandinin's conceptualization of teachers' professional identity in terms of 'stories to live by' and through a life-history lens, this multiple case study aimed to respond to the following questions: (a) How do three preservice elementary teachers view themselves as future science teachers? (b) How have the participants' life histories shaped their science identity trajectories? In order to characterize the participants' formation of science identities over time, various data regarding their life histories in relation to science were collected: science biographies, self-portraits, interviews, reflective journals, lesson plans, and classroom observations. The analysis of the data illustrated how the three participants' identities have been in formation from the early years of their lives and how various events, experiences, and interactions had shaped their identities through time and across contexts. These findings are discussed alongside implications for theory, specifically, identity and life-history intersections, for teacher preparation, and for research related to explorations of beginning elementary teachers' identity trajectories.

Putting all your eggs in one basket: life-history strategies, bet hedging, and diversification.

Science.gov (United States)

White, Andrew Edward; Li, Yexin Jessica; Griskevicius, Vladas; Neuberg, Steven L; Kenrick, Douglas T

2013-05-01

Diversification of resources is a strategy found everywhere from the level of microorganisms to that of giant Wall Street investment firms. We examine the functional nature of diversification using life-history theory-a framework for understanding how organisms navigate resource-allocation trade-offs. This framework suggests that diversification may be adaptive or maladaptive depending on one's life-history strategy and that these differences should be observed under conditions of threat. In three studies, we found that cues of mortality threat interact with one index of life-history strategy, childhood socioeconomic status (SES), to affect diversification. Among those from low-SES backgrounds, mortality threat increased preferences for diversification. However, among those from high-SES backgrounds, mortality threat had the opposite effect, inclining people to put all their eggs in one basket. The same interaction pattern emerged with a potential biomarker of life-history strategy, oxidative stress. These findings highlight when, and for whom, different diversification strategies can be advantageous.

Book Review: Evolutionary Ecology of Birds: Life Histories, Mating ...

African Journals Online (AJOL)

Abstract. Book Title: Evolutionary Ecology of Birds: Life Histories, Mating Systems and Extinction. Book Authors: P.M. Bennett & I.P.F. Owens. Oxford University. Press. 2002. Pp. 272. Price £24.95 (paperback). ISBN 0 19 851089 6.

Caring Decisions: The Development of a Written Resource for Parents Facing End-of-Life Decisions

OpenAIRE

Xafis, Vicki; Gillam, Lynn; Hynson, Jenny; Sullivan, Jane; Cossich, Mary; Wilkinson, Dominic

2015-01-01

Background: Written resources in adult intensive care have been shown to benefit families facing end of life (EoL) decisions. There are few resources for parents making EoL decisions for their child and no existing resources addressing ethical issues. TheCaring Decisionshandbook and website were developed to fill these gaps. Aim: We discuss the development of the resources, modification after reviewer feedback and findings from initial pilot implementation. Design: A targeted...

End-of-life decisions in Malaysia: Adequacies of ethical codes and developing legal standards.

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Kassim, Puteri Nemie Jahn; Alias, Fadhlina

2015-06-01

End-of-life decision-making is an area of medical practice in which ethical dilemmas and legal interventions have become increasingly prevalent. Decisions are no longer confined to clinical assessments; rather, they involve wider considerations such as a patient's religious and cultural beliefs, financial constraints, and the wishes and needs of family members. These decisions affect everyone concerned, including members of the community as a whole. Therefore it is imperative that clear ethical codes and legal standards are developed to help guide the medical profession on the best possible course of action for patients. This article considers the relevant ethical, codes and legal provisions in Malaysia governing certain aspects of end-of-life decision-making. It highlights the lack of judicial decisions in this area as well as the limitations with the Malaysian regulatory system. The article recommends the development of comprehensive ethical codes and legal standards to guide end-of-life decision-making in Malaysia.

Parental care trade-offs and life-history relationships in insects.

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Gilbert, James D J; Manica, Andrea

2010-08-01

Insect parental care is extensive and varied, but its life-history implications have never been comparatively tested. Using original and literature data, we tested predictions about egg size, egg number (lifetime fecundity), and body size under different parental care modes across a phylogeny of 287 insect species. Life-history theory and both comparative and intraspecific evidence from ectotherms suggest parental care should select for bigger, fewer eggs, but that allometric scaling of egg size and lifetime fecundity may depend on whether care consists of provisioning (density-dependent offspring survival) or merely guarding (density-independent offspring survival). Against expectation, egg size was indistinguishable among parental care modes, covarying only with body size. This refutes most theory of egg size evolution under parental care. Lifetime fecundity scaled differently depending on parental investment-positively under no care and guarding, as in most ectotherms, but negatively under provisioning. Reproductive allocation in provisioning insects resembled that in mammals and birds, also groups with obligate provisioning. We propose that the metabolic demands of multiple offspring must scale with species body size more steeply than the parent's provisioning capacity, resulting in larger females laying fewer eggs. These patterns lay the groundwork for a more general understanding of parental care and life history.

Can understanding squid life-history strategies and recruitment ...

African Journals Online (AJOL)

Current views of the links between life-history strategies and recruitment processes in fish are contrasted with the pattern emerging for squid. A general perspective is that the roles of space and time are reversed in the two groups, suggesting that management strategies also should differ. The space/time reversal appears to ...

Family communication and decision making at the end of life: a literature review.

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Wallace, Cara L

2015-06-01

Patients and families coping with a terminal illness are faced with a number of decisions over the course of their disease. The role that family communication plays in the process of decision making is an important one. The objectives for this review are to examine the current state of empirical literature on the relationship between family communication and decision making about end-of-life care, to identify gaps, and to discuss implications for policy, practice, and future research. Articles were identified using systematic keyword searches within the following relevant databases: Academic Search Complete, CINAHL Plus, Communications and Mass Media Complete, ERIC, PsychINFO, MEDLINE, SocINDEX, and ProQuest. The three bodies of relevant literature that emerged during this review include: (1) the importance of family communication at the end of life (EoL); (2) family decision making at the EoL; and (3) the interrelationship of communication (both within the family and with healthcare professionals) and decision making at the EoL. While the literature highlights the role of communication between medical professionals and the patient or family members, there is very little focus on the process of how family communication among the family members themselves contributes to decision making at the end of life. Barriers to end-of-life care are important considerations for helping patients to access timely and appropriate services. Understanding the pertinent role of family communication as it relates to the decision for EoL care is the first step in working to provide another avenue for overcoming these barriers.

Old world versus new world: life-history alterations in a successful invader introduced across Europe.

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Fox, Michael G; Copp, Gordon H

2014-02-01

We examined differences in pumpkinseed (Lepomis gibbosus) life-history traits between native North American and introduced European populations, and tested three life-history predictions related to the effect of temperature, growth, waterbody size, and the presence/absence of predators on native and non-native populations. Pumpkinseed populations exhibit more 'opportunistic' traits (earlier maturity, smaller size at maturity, and higher reproductive allocation) in their introduced European range than those in their native range. Predictions of life-history traits were improved when indicators of juvenile growth rate (mean length at age 2), waterbody size (surface area), and thermal regime (air temperature degree-days above 10 °C) were incorporated into models along with continental location, but European pumpkinseed populations exhibit more opportunistic life-history traits than North American populations even when these factors are accounted for. Native pumpkinseed in waterbodies containing piscivores mature later and at a larger size, and have lower gonadosomatic indices than those in waterbodies lacking piscivores, whereas there is no significant difference in the same three life-history traits between European waterbodies containing or lacking piscivores. Because congeneric competitors of the pumpkinseed are absent from Europe, the apparent absence of a predator life-history effect there could also be due to the absence of the major sunfish competitors. In either case, the evolution and maintenance of more opportunistic traits in European pumpkinseed can likely be attributed to enemy release, and this may explain the successful establishment and spread of pumpkinseed in many parts of Europe.

Perceived risks around choice and decision making at end-of-life: a literature review.

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Wilson, F; Gott, M; Ingleton, C

2013-01-01

the World Health Organization identifies meeting patient choice for care as central to effective palliative care delivery. Little is known about how choice, which implies an objective balancing of options and risks, is understood and enacted through decision making at end-of-life. to explore how perceptions of 'risk' may inform decision-making processes at end-of-life. an integrative literature review was conducted between January and February 2010. Papers were reviewed using Hawker et al.'s criteria and evaluated according to clarity of methods, analysis and evidence of ethical consideration. All literature was retained as background data, but given the significant international heterogeneity the final analysis specifically focused on the UK context. the databases Medline, PsycINFO, Assia, British Nursing Index, High Wire Press and CINAHL were explored using the search terms decision*, risk, anxiety, hospice and palliative care, end-of-life care and publication date of 1998-2010. thematic analysis of 25 papers suggests that decision making at end-of-life is multifactorial, involving a balancing of risks related to caregiver support; service provider resources; health inequalities and access; challenges to information giving; and perceptions of self-identity. Overall there is a dissonance in understandings of choice and decision making between service providers and service users. the concept of risk acknowledges the factors that shape and constrain end-of-life choices. Recognition of perceived risks as a central factor in decision making would be of value in acknowledging and supporting meaningful decision making processes for patients with palliative care needs and their families.

Life history and the evolution of parental care.

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Klug, Hope; Bonsall, Michael B

2010-03-01

Patterns of parental care are strikingly diverse in nature, and parental care is thought to have evolved repeatedly multiple times. Surprisingly, relatively little is known about the most general conditions that lead to the origin of parental care. Here, we use a theoretical approach to explore the basic life-history conditions (i.e., stage-specific mortality and maturation rates, reproductive rates) that are most likely to favor the evolution of some form of parental care from a state of no care. We focus on parental care of eggs and eggs and juveniles and consider varying magnitudes of the benefits of care. Our results suggest that parental care can evolve under a range of life-history conditions, but in general will be most strongly favored when egg death rate in the absence of care is high, juvenile survival in the absence of care is low (for the scenario in which care extends into the juvenile stage), adult death rate is relatively high, egg maturation rate is low, and the duration of the juvenile stage is relatively short. Additionally, parental care has the potential to be favored at a broad range of adult reproductive rates. The relative importance of these life-history conditions in favoring or limiting the evolution of care depends on the magnitude of the benefits of care, the relationship between initial egg allocation and subsequent offspring survival, and whether care extends into the juvenile stage. The results of our model provide a general set of predictions regarding when we would expect parental care to evolve from a state of no care, and in conjunction with other work on the topic, will enhance our understanding of the evolutionary dynamics of parental care and facilitate comparative analyses.

Integration of Social Aspects in Decision Support, Based on Life Cycle Thinking

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Pere Fullana-i-Palmer

2011-03-01

Full Text Available Recently increasing attention has been paid to complementing environmental Life Cycle Assessment (LCA with social aspects. The paper discusses the selection of social impacts and indicators from existing frameworks like Social Life Cycle Assessment (SLCA and Social Impact Assessment (SIA. Two ongoing case studies, addressing sustainability assessment within decision support, were considered: (1 Integrated Water Resources Management (IWRM in Indonesia; and (2 Integrated Packaging Waste Management in Spain and Portugal (FENIX. The focus was put on social impacts occurring due to decisions within these systems, such as choice of technologies, practices or suppliers. Thus, decision makers—here understood as intended users of the studies’ results—are not consumers that buy (or do not buy a product, such as in recent SLCA case-studies, but mainly institutions that decide about the design of the water or packaging waste management system. Therefore, in the FENIX project, a list of social impacts identified from literature was sent to the intended users to be ranked according to their priorities. Finally, the paper discusses to what extent the entire life cycle is reflected in SLCA impact categories and indicators, and explains how both life-cycle and on-site-related social impacts were chosen to be assessed. However, not all indicators in the two projects will assess all stages of the life cycle, because of their varying relevance in the different stages, data availability and practical interest of decision makers.

Age and life course location as interpretive resources for decisions regarding disclosure of HIV to parents and children: Findings from the HIV and later life study.

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Rosenfeld, Dana; Ridge, Damien; Catalan, Jose; Delpech, Valerie

2016-08-01

Studies of disclosure amongst older people living with HIV (PLWH) are uninformed by critical social-gerontological approaches that can help us to appreciate how older PLWH see and treat age as relevant to disclosure of their HIV status. These approaches include an ethnomethodologically-informed social constructionism that explores how 'the' life course (a cultural framework depicting individuals' movement through predictable developmental stages from birth to death) is used as an interpretive resource for determining self and others' characteristics, capacities, and social circumstances: a process Rosenfeld and Gallagher (2002) termed 'lifecoursing'. Applying this approach to our analysis of 74 life-history interviews and three focus groups with older (aged 50+) people living with HIV in the United Kingdom, we uncover the central role that lifecoursing plays in participants' decision-making surrounding disclosure of their HIV to their children and/or older parents. Analysis of participants' accounts uncovered four criteria for disclosure: the relevance of their HIV to the other, the other's knowledge about HIV, the likelihood of the disclosure causing the other emotional distress, and the other's ability to keep the disclosed confidential. To determine if these criteria were met in relation to specific children and/or elders, participants engaged in lifecoursing, evaluating the other's knowledge of HIV, and capacity to appropriately manage the disclosure, by reference to their age. The use of assumptions about age and life-course location in decision-making regarding disclosure of HIV reflects a more nuanced engagement with age in the disclosure decision-making process than has been captured by previous research into HIV disclosure, including on the part of people aging with HIV. Copyright © 2016 Elsevier Inc. All rights reserved.

Life history and demographic drivers of reservoir competence for three tick-borne zoonotic pathogens.

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Richard S Ostfeld

Full Text Available Animal and plant species differ dramatically in their quality as hosts for multi-host pathogens, but the causes of this variation are poorly understood. A group of small mammals, including small rodents and shrews, are among the most competent natural reservoirs for three tick-borne zoonotic pathogens, Borrelia burgdorferi, Babesia microti, and Anaplasma phagocytophilum, in eastern North America. For a group of nine commonly-infected mammals spanning >2 orders of magnitude in body mass, we asked whether life history features or surrogates for (unknown encounter rates with ticks, predicted reservoir competence for each pathogen. Life history features associated with a fast pace of life generally were positively correlated with reservoir competence. However, a model comparison approach revealed that host population density, as a proxy for encounter rates between hosts and pathogens, generally received more support than did life history features. The specific life history features and the importance of host population density differed somewhat between the different pathogens. We interpret these results as supporting two alternative but non-exclusive hypotheses for why ecologically widespread, synanthropic species are often the most competent reservoirs for multi-host pathogens. First, multi-host pathogens might adapt to those hosts they are most likely to experience, which are likely to be the most abundant and/or frequently bitten by tick vectors. Second, species with fast life histories might allocate less to certain immune defenses, which could increase their reservoir competence. Results suggest that of the host species that might potentially be exposed, those with comparatively high population densities, small bodies, and fast pace of life will often be keystone reservoirs that should be targeted for surveillance or management.

Mental competence and surrogate decision-making towards the end of life.

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Strätling, M; Scharf, V E; Schmucker, P

2004-01-01

German legislation demands that decisions about the treatment of mentally incompetent patients require an 'informed consent'. If this was not given by the patient him-/herself before he/she became incompetent, it has to be sought by the physician from a guardian, who has to be formally legitimized before. Additionally this surrogate has to seek the permission of a Court of Guardianship (Vormundschaftsgericht), if he/she intends to consent to interventions, which pose significant risks to the health or the life of the person under his/her care. This includes 'end-of-life decisions'. Deviations from this procedure are only allowed in acute emergencies or cases of 'medical futility'. On the basis of epidemiological and demographical data it can be shown that the vast majority of surrogate decisions on incompetent patients in Germany is not covered by legally valid consent. Moreover, the data suggests that if consent were to be requested according to the legal regulations, both the legal and medical system could realistically never cope with the practical consequences of this. Additionally, empiric research has revealed serious deficits concerning medical 'end of life-decisions' and practical performance in palliative care. As a consequence a multidisciplinary discussion has developed in Germany about the reform of present legislation with respect to key-issues like the assessment of mental competence, the options for exercising patient self-determination via advance directives and durable powers of attorney, the improvement of palliative care facilities, the clarification of formal procedures for surrogate decision-making in health care and towards the end of life and the possibilities and their limitations of controlling these decision-making processes 'externally' (e.g., by Guardianship Courts or committees). The authors discuss those proposals, which clearly dominate the present debate: They all aim to comply with the scientific basis of German law, jurisdiction

Molecular phylogenetics of the genus Neoconocephalus (orthoptera, tettigoniidae and the evolution of temperate life histories.

Directory of Open Access Journals (Sweden)

Robert L Snyder

Full Text Available BACKGROUND: The katydid genus Neoconocephalus (25+ species has a prominent acoustic communication system and occurs in large parts of the Neotropics and Nearctic. This group has been subject of numerous behavioral, physiological, and evolutionary studies of its acoustic communication system. Two distinct life histories occur in this group: The tropical life history incorporates multiple generations/year and direct egg development without environmental triggers. Temperate life history is characterized by overwintering in the egg stage, cold trigger of egg development, and one generation/year. This study reconstructs the phylogenetic relationships within the genus to (1 determine the evolutionary history of the temperate life history, and (2 to support comparative studies of evolutionary and physiological problems in this genus. METHODOLOGY/PRINCIPAL FINDINGS: We used Amplified Fragment Length Polymorphisms (AFLP, and sequences of two nuclear loci and one mitochondrial locus to reconstruct phylogenetic relationships. The analysis included 17 ingroup and two outgroup species. AFLP and mitochondrial data provided resolution at the species level while the two nuclear loci revealed only deeper nodes. The data sets were combined in a super-matrix to estimate a total evidence tree. Seven of the temperate species form a monophyletic group; however, three more temperate species were placed as siblings of tropical species. CONCLUSIONS/SIGNIFICANCE: Our analyses support the reliability of the current taxonomic treatment of the Neoconocephalus fauna of Caribbean, Central, and North America. Ancestral state reconstruction of life history traits was not conclusive, however at least four transitions between life histories occurred among our sample of species. The proposed phylogeny will strengthen conclusions from comparative work in this group.

Advance Directive in End of Life Decision-Making among the Yoruba of South-Western Nigeria.

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Jegede, Ayodele Samuel; Adegoke, Olufunke Olufunsho

2016-11-01

End-of-life decision making is value-laden within the context of culture and bioethics. Also, ethics committee role is difficult to understand on this, thus need for ethnomethodological perspective in an expanding bioethical age. Anthropological approach was utilized to document Yoruba definition and perspective of death, cultural beliefs about end-of-life decision making, factors influencing it and ethics committee role. Interviews were conducted among selected Yoruba resident in Akinyele LGA, Oyo State, Nigeria. Content analytical approach was used for data analysis. Yoruba culture, death is socially constructed having spiritual, physical and social significance. Relationship between the dying and significant others influences decision making. Hierarchy of authority informs implementing traditional advance directive. Socialization, gender, patriarchy, religious belief and tradition are major considerations in end-of-life decision making. Awareness, resource allocation and advocacy are important ethics committees' roles. Further research into cultural diversity of end-of-life decision making will strengthen ethical practice in health care delivery.

Early life history and spatiotemporal changes in distribution of the rediscovered Suwannee moccasinshell Medionidus walkeri (Bivalvia: Unionidae)

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Johnson, Nathan A.; Mcleod, John; Holcomb, Jordan; Rowe, Matthew T.; Williams, James D.

2016-01-01

Accurate distribution data are critical to the development of conservation and management strategies for imperiled species, particularly for narrow endemics with life history traits that make them vulnerable to extinction. Medionidus walkeri is a rare freshwater mussel endemic to the Suwannee River Basin in southeastern North America. This species was rediscovered in 2012 after a 16-year hiatus between collections and is currently proposed for listing under the Endangered Species Act. Our study fills knowledge gaps regarding changes in distribution and early life history requirements of M. walkeri. Spatiotemporal changes in M. walkeri distribution were displayed using a conservation status assessment map incorporating metadata from 98 historical (1916–1999) and 401 recent (2000–2015) site surveys from museums and field notes representing records for 312 specimens. Recent surveys detected M. walkeri only in the middle Suwannee subbasin (n = 86, 22 locations) and lower Santa Fe subbasin (n = 2, 2 locations), and it appears the species may be extirpated from 67% of historically occupied 10-digit HUCs. In our laboratory experiments, M. walkeri successfully metamorphosed on Percina nigrofasciata (56.2% ± 8.9) and Etheostoma edwini (16.1% ± 7.9) but not on Trinectes maculatus, Lepomis marginatus, Notropis texanus, Noturus leptacanthus, Etheostoma fusiforme, or Gambusia holbrooki. We characterize M. walkeri as a lure-displaying host fish specialist and a long-term brooder (bradytictic), gravid from fall to early summer of the following year. The early life history and distribution data presented here provide the baseline framework for listing decisions and future efforts to conserve and recover the species.

Prey life-history and bioenergetic responses across a predation gradient.

Science.gov (United States)

Rennie, M D; Purchase, C F; Shuter, B J; Collins, N C; Abrams, P A; Morgan, G E

2010-10-01

To evaluate the importance of non-consumptive effects of predators on prey life histories under natural conditions, an index of predator abundance was developed for naturally occurring populations of a common prey fish, the yellow perch Perca flavescens, and compared to life-history variables and rates of prey energy acquisition and allocation as estimated from mass balance models. The predation index was positively related to maximum size and size at maturity in both male and female P. flavescens, but not with life span or reproductive investment. The predation index was positively related to size-adjusted specific growth rates and growth efficiencies but negatively related to model estimates of size-adjusted specific consumption and activity rates in both vulnerable (small) and invulnerable (large) size classes of P. flavescens. These observations suggest a trade-off between growth and activity rates, mediated by reduced activity in response to increasing predator densities. Lower growth rates and growth efficiencies in populations with fewer predators, despite increased consumption suggests either 1) a reduction in prey resources at lower predator densities or 2) an intrinsic cost of rapid prey growth that makes it unfavourable unless offset by a perceived threat of predation. This study provides evidence of trade-offs between growth and activity rates induced by predation risk in natural prey fish populations and illustrates how behavioural modification induced through predation can shape the life histories of prey fish species. © 2010 The Authors. Journal compilation © 2010 The Fisheries Society of the British Isles.

End-of-life decisions for people with intellectual disabilities, an interview study with patient representatives.

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Wagemans, Annemieke M A; Van Schrojenstein Lantman-de Valk, Henny M J; Proot, Ireen M; Metsemakers, Job; Tuffrey-Wijne, Irene; Curfs, Leopold M G

2013-09-01

Not much is known about the process of end-of-life decision-making for people with intellectual disabilities. To clarify the process of end-of-life decision-making for people with intellectual disabilities from the perspective of patient representatives. A qualitative study based on semi-structured interviews, recorded digitally and transcribed verbatim. Data were analysed using Grounded Theory procedures. We interviewed 16 patient representatives after the deaths of 10 people with intellectual disabilities in the Netherlands. The core category 'Deciding for someone else' describes the context in which patient representatives took end-of-life decisions. The patient representatives felt highly responsible for the outcomes. They had not involved the patients in the end-of-life decision-making process, nor any professionals other than the doctor. The categories of 'Motives' and 'Support' were connected to the core category of 'Deciding for someone else'. 'Motives' refers to the patient representatives' ideas about quality of life, prevention from suffering, patients who cannot understand the burden of interventions and emotional reasons reported by patient representatives. 'Support' refers to the support that patient representatives wanted the doctors to give to them in the decision-making process. From the perspective of the patient representatives, the process of end-of-life decision-making can be improved by ensuring clear roles and an explicit description of the tasks and responsibilities of all participants. Regular discussion between everyone involved including people with intellectual disabilities themselves can improve knowledge about each other's motives for end-of-decisions and can clarify expectations towards each other.

End-of-life decision making is more than rational.

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Eliott, Jaklin A; Olver, Ian N

2005-01-01

Most medical models of end-of-life decision making by patients assume a rational autonomous adult obtaining and deliberating over information to arrive at some conclusion. If the patient is deemed incapable of this, family members are often nominated as substitutes, with assumptions that the family are united and rational. These are problematic assumptions. We interviewed 23 outpatients with cancer about the decision not to resuscitate a patient following cardiopulmonary arrest and examined their accounts of decision making using discourse analytical techniques. Our analysis suggests that participants access two different interpretative repertoires regarding the construct of persons, invoking a 'modernist' repertoire to assert the appropriateness of someone, a patient or family, making a decision, and a 'romanticist' repertoire when identifying either a patient or family as ineligible to make the decision. In determining the appropriateness of an individual to make decisions, participants informally apply 'Sanity' and 'Stability' tests, assessing both an inherent ability to reason (modernist repertoire) and the presence of emotion (romanticist repertoire) which might impact on the decision making process. Failure to pass the tests respectively excludes or excuses individuals from decision making. The absence of the romanticist repertoire in dominant models of patient decision making has ethical implications for policy makers and medical practitioners dealing with dying patients and their families.

Competition as a source of constraint on life history evolution in natural populations.

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Wilson, A J

2014-01-01

Competition among individuals is central to our understanding of ecology and population dynamics. However, it could also have major implications for the evolution of resource-dependent life history traits (for example, growth, fecundity) that are important determinants of fitness in natural populations. This is because when competition occurs, the phenotype of each individual will be causally influenced by the phenotypes, and so the genotypes, of competitors. Theory tells us that indirect genetic effects arising from competitive interactions will give rise to the phenomenon of 'evolutionary environmental deterioration', and act as a source of evolutionary constraint on resource-dependent traits under natural selection. However, just how important this constraint is remains an unanswered question. This article seeks to stimulate empirical research in this area, first highlighting some patterns emerging from life history studies that are consistent with a competition-based model of evolutionary constraint, before describing several quantitative modelling strategies that could be usefully applied. A recurrent theme is that rigorous quantification of a competition's impact on life history evolution will require an understanding of the causal pathways and behavioural processes by which genetic (co)variance structures arise. Knowledge of the G-matrix among life history traits is not, in and of itself, sufficient to identify the constraints caused by competition.

Bringing history to life: simulating landmark experiments in psychology.

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Boynton, David M; Smith, Laurence D

2006-05-01

The course in history of psychology can be challenging for students, many of whom enter it with little background in history and faced with unfamiliar names and concepts. The sheer volume of material can encourage passive memorization unless efforts are made to increase student involvement. As part of a trend toward experiential history, historians of science have begun to supplement their lectures with demonstrations of classic physics experiments as a way to bring the history of science to life. Here, the authors report on computer simulations of five landmark experiments from early experimental psychology in the areas of reaction time, span of attention, and apparent motion. The simulations are designed not only to permit hands-on replication of historically important results but also to reproduce the experimental procedures closely enough that students can gain a feel for the nature of early research and the psychological processes being studied.

Population-specific life histories contribute to metapopulation viability

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Halsey, Samniqueka J.; Bell, Timothy J.; McEachern, A. Kathryn; Pavlovic, Noel B.

2016-01-01

Restoration efforts can be improved by understanding how variations in life-history traits occur within populations of the same species living in different environments. This can be done by first understanding the demographic responses of natural occurring populations. Population viability analysis continues to be useful to species management and conservation with sensitivity analysis aiding in the understanding of population dynamics. In this study, using life-table response experiments and elasticity analyses, we investigated how population-specific life-history demographic responses contributed to the metapopulation viability of the Federally threatened Pitcher's thistle (Cirsium pitcheri). Specifically, we tested the following hypotheses: (1) Subpopulations occupying different environments within a metapopulation have independent demographic responses and (2) advancing succession results in a shift from a demographic response focused on growth and fecundity to one dominated by stasis. Our results showed that reintroductions had a positive contribution to the metapopulation growth rate as compared to native populations which had a negative contribution. We found no difference in succession on the contribution to metapopulation viability. In addition, we identified distinct population-specific contributions to metapopulation viability and were able to associate specific life-history demographic responses. For example, the positive impact of Miller High Dunes population on the metapopulation growth rate resulted from high growth contributions, whereas increased time of plant in stasis for the State Park Big Blowout population resulted in negative contributions. A greater understanding of how separate populations respond in their corresponding environment may ultimately lead to more effective management strategies aimed at reducing extinction risk. We propose the continued use of sensitivity analyses to evaluate population-specific demographic influences on

Environmental effects on growth, reproduction, and life-history traits of loggerhead turtles

NARCIS (Netherlands)

Marn, Nina; Jusup, Marko; Legović, Tarzan; Kooijman, S. A.L.M.; Klanjšček, Tin

2017-01-01

Understanding the relationship between the environmental conditions and life-history traits (such as growth, reproduction, and size at specific life stages) is important for understanding the population dynamics of a species and for constructing adaptable, relevant, and efficient conservation

Mutation accumulation may be a minor force in shaping life history traits

DEFF Research Database (Denmark)

Dańko, Maciej Jan; Kozłowski, Jan; Vaupel, James Walton

2012-01-01

-strings to capture different age-specific mutational patterns. Each pattern represents a genotype and for each genotype we find the life history strategy that maximizes fitness. Genotypes compete with each other and are subject to selection and to new mutations over generations until equilibrium in gene......-frequencies is reached. The mutation-selection equilibrium provides information about mutational load and the differential effects of mutations on a life history trait--the optimal age at maturity. We find that mutations accumulate only at ages with negligible impact on fitness and that mutation accumulation has very...

Ethical decision-making near the end of life.

Science.gov (United States)

Finucane, T E; Harper, M

1996-05-01

For ethical decision-making near the end of life, autonomy is the moral North Star. At the same time, for some treatments, the burdens so clearly outweigh benefits that physicians may make a judgment not to offer the treatment. This is often clearer in surgery. A person with colon cancer and metastases may not insist on resection of the metastases. For some reason, some treatments have escaped these logical constraints. Attempted resuscitation of a dying patient is a good example. The circumstances in which a physician may make choices on behalf of a competent, terminally-ill patient without consent, and even without notification, are hotly debated, but data suggest that physicians do so frequently. Patients who lack capacity present even more difficult challenges. Advance directives, when available, can be extremely helpful, but even with them difficult problems can remain. If advance directives have not been established, family and close friends are an obvious source of guidance. Their legal role varies in different jurisdictions; in practice, they are crucial in bedside decision-making. Guardianship and alternatives to it remain a poor last resort. Euthanasia is a very difficult problem. We believe it is semantically misleading to lump under the term "passive euthanasia" those circumstances where potentially life-sustaining treatment is withheld or withdrawn. The tension between patient autonomy and medical common sense remains unresolved within the "futility" controversy. The authors believe it serves no purpose to discuss carefully with dying patients propositions that are nonsense. At the same time, physicians must not confuse decisions about quality of life with judgements about treatment effectiveness. We believe that what many, although not all, dying patients want are physicians with intelligent compassion who can take care of them through the dying process.

Population Variation in the Life History of a Land Fish, Alticus arnoldorum, and the Effects of Predation and Density.

Directory of Open Access Journals (Sweden)

Edward R M Platt

Full Text Available Life history variation can often reflect differences in age-specific mortality within populations, with the general expectation that reproduction should be shifted away from ages experiencing increased mortality. Investigators of life history in vertebrates frequently focus on the impact of predation, but there is increasing evidence that predation may have unexpected impacts on population density that in turn prompt unexpected changes in life history. There are also other reasons why density might impact life history independently of predation or mortality more generally. We investigated the consequences of predation and density on life history variation among populations of the Pacific leaping blenny, Alticus arnoldorum. This fish from the island of Guam spends its adult life out of the water on rocks in the splash zone, where it is vulnerable to predation and can be expected to be sensitive to changes in population density that impact resource availability. We found populations invested more in reproduction as predation decreased, while growth rate varied primarily in response to population density. These differences in life history among populations are likely plastic given the extensive gene flow among populations revealed by a previous study. The influence of predation and density on life history was unlikely to have operated independently of each other, with predation rate tending to be associated with reduced population densities. Taken together, our results suggest predation and density can have complex influences on life history, and that plastic life history traits could allow populations to persist in new or rapidly changing environments.

Towards life-cycle awareness in decision support tools for engineering design

OpenAIRE

Nergård, Henrik; Sandberg, Marcus; Larsson, Tobias

2009-01-01

In this paper a decision support tool with the focus on how to generate and visualize decision base coupled to the business agreement is outlined and discussed. Decision support tools for the early design phases are few and especially tools that visualize the readiness level of activities throughout the product life-cycle. Aiming for the sustainable society there is an indication that business-to-business manufacturers move toward providing a function rather than selling off the hardware and ...

Twelve fundamental life histories evolving through allocation-dependent fecundity and survival.

Science.gov (United States)

Johansson, Jacob; Brännström, Åke; Metz, Johan A J; Dieckmann, Ulf

2018-03-01

An organism's life history is closely interlinked with its allocation of energy between growth and reproduction at different life stages. Theoretical models have established that diminishing returns from reproductive investment promote strategies with simultaneous investment into growth and reproduction (indeterminate growth) over strategies with distinct phases of growth and reproduction (determinate growth). We extend this traditional, binary classification by showing that allocation-dependent fecundity and mortality rates allow for a large diversity of optimal allocation schedules. By analyzing a model of organisms that allocate energy between growth and reproduction, we find twelve types of optimal allocation schedules, differing qualitatively in how reproductive allocation increases with body mass. These twelve optimal allocation schedules include types with different combinations of continuous and discontinuous increase in reproduction allocation, in which phases of continuous increase can be decelerating or accelerating. We furthermore investigate how this variation influences growth curves and the expected maximum life span and body size. Our study thus reveals new links between eco-physiological constraints and life-history evolution and underscores how allocation-dependent fitness components may underlie biological diversity.

Fast–slow continuum and reproductive strategies structure plant life-history variation worldwide

NARCIS (Netherlands)

Salguero-Gómez, Roberto; Jones, Owen R.; Jongejans, Eelke; Blomberg, Simon; Hodgson, D.; Zuidema, P.A.; Kroon, de Hans; Buckley, Yvonne M.

2016-01-01

The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous

Life-History and Developmental Antecedents of Female Vocational Preferences.

Science.gov (United States)

Reichel, Laura S.; Muchinsky, Paul M.

1995-01-01

A group of 296 female undergraduates completed the Strong Interest Inventory, Biographical Questionnaire, Bem Sex-Role Inventory, and Self-Esteem Inventory. Life history was a better predictor of vocational interests than either sex-role orientation or self-esteem. The only significant exception was that Femininity correlated with interest in…

Comparison of the population structure and life-history parameters ...

African Journals Online (AJOL)

Blacktail seabream Diplodus capensis were sampled from proximate (10 km apart) exploited and unexploited areas in southern Angola to compare their population structures and life-history parameters. Females dominated the larger size and older age classes in the unexploited area. In the exploited area the length and ...

Differential reproductive responses to stress reveal the role of life-history strategies within a species.

Science.gov (United States)

Schultner, J; Kitaysky, A S; Gabrielsen, G W; Hatch, S A; Bech, C

2013-11-22

Life-history strategies describe that 'slow'- in contrast to 'fast'-living species allocate resources cautiously towards reproduction to enhance survival. Recent evidence suggests that variation in strategies exists not only among species but also among populations of the same species. Here, we examined the effect of experimentally induced stress on resource allocation of breeding seabirds in two populations with contrasting life-history strategies: slow-living Pacific and fast-living Atlantic black-legged kittiwakes. We tested the hypothesis that reproductive responses in kittiwakes under stress reflect their life-history strategies. We predicted that in response to stress, Pacific kittiwakes reduce investment in reproduction compared with Atlantic kittiwakes. We exposed chick-rearing kittiwakes to a short-term (3-day) period of increased exogenous corticosterone (CORT), a hormone that is released during food shortages. We examined changes in baseline CORT levels, parental care and effects on offspring. We found that kittiwakes from the two populations invested differently in offspring when facing stress. In response to elevated CORT, Pacific kittiwakes reduced nest attendance and deserted offspring more readily than Atlantic kittiwakes. We observed lower chick growth, a higher stress response in offspring and lower reproductive success in response to CORT implantation in Pacific kittiwakes, whereas the opposite occurred in the Atlantic. Our findings support the hypothesis that life-history strategies predict short-term responses of individuals to stress within a species. We conclude that behaviour and physiology under stress are consistent with trade-off priorities as predicted by life-history theory. We encourage future studies to consider the pivotal role of life-history strategies when interpreting inter-population differences of animal responses to stressful environmental events.

Quality of Living and Dying: Pediatric Palliative Care and End-of-Life Decisions in the Netherlands.

Science.gov (United States)

Brouwer, Marije; Maeckelberghe, Els; DE Weerd, Willemien; Verhagen, Eduard

2018-07-01

In 2002, The Netherlands continued its leadership in developing rules and jurisdiction regarding euthanasia and end-of-life decisions by implementing the Euthanasia Act, which allows euthanasia for patients 12 years of age and older. Subsequently, in 2005, the regulation on active ending of life for newborns was issued. However, more and more physicians and parents have stated that the age gap between these two regulations-children between 1 and 12 years old-is undesirable. These children should have the same right to end their suffering as adults and newborn infants. An extended debate on pediatric euthanasia ensued, and currently the debate is ongoing as to whether legislation should be altered in order to allow pediatric euthanasia. An emerging major question regards the active ending of life in the context of palliative care: How does a request for active ending of life relate to the care that is given to children in the palliative phase? Until now, the distinction between palliative care and end-of-life decisions continues to remain unclear, making any discussion about their mutual in- and exclusiveness hazardous at best. In this report, therefore, we aim to provide insight into the relationship between pediatric palliative care and end-of-life decisions, as understood in the Netherlands. We do so by first providing an overview of the (legal) rules and regulations regarding euthanasia and active ending of life, followed by an analysis of the relationship between these two, using the Dutch National Guidelines for Palliative Care for Children. The results of this analysis revealed two major and related features of palliative care and end-of-life decisions for children: (1) palliative care and end-of-life decisions are part of the same process, one that focuses both on quality of living and quality of dying, and (2) although physicians are seen as ultimately responsible for making end-of-life decisions, the involvement of parents and children in this decision is

Can sexual selection drive female life histories? A comparative study on Galliform birds

OpenAIRE

Kolm, N.; Stein, R. W.; Mooers, A. O.; Verspoor, J. J.; Cunningham, E. J. A.

2007-01-01

Sexual selection has been identified as a major evolutionary force shaping male life history traits but its impact on female life history evolution is less clear. Here we examine the impact of sexual selection on three key female traits (body size, egg size and clutch size) in Galliform birds. Using comparative independent contrast analyses and directional DISCRETE analyses, based on published data and a new genera-level supertree phylogeny of Galliform birds, we investigated how sexual selec...

Life history strategy and young adult substance use.

Science.gov (United States)

Richardson, George B; Chen, Ching-Chen; Dai, Chia-Liang; Swoboda, Christopher M

2014-11-03

This study tested whether life history strategy (LHS) and its intergenerational transmission could explain young adult use of common psychoactive substances. We tested a sequential structural equation model using data from the National Longitudinal Survey of Youth. During young adulthood, fast LHS explained 61% of the variance in overall liability for substance use. Faster parent LHS predicted poorer health and lesser alcohol use, greater neuroticism and cigarette smoking, but did not predict fast LHS or overall liability for substance use among young adults. Young adult neuroticism was independent of substance use controlling for fast LHS. The surprising finding of independence between parent and child LHS casts some uncertainty upon the identity of the parent and child LHS variables. Fast LHS may be the primary driver of young adult use of common psychoactive substances. However, it is possible that the young adult fast LHS variable is better defined as young adult mating competition. We discuss our findings in depth, chart out some intriguing new directions for life history research that may clarify the dimensionality of LHS and its mediation of the intergenerational transmission of substance use, and discuss implications for substance abuse prevention and treatment.

Life History Strategy and Young Adult Substance Use

Directory of Open Access Journals (Sweden)

George B. Richardson

2014-04-01

Full Text Available This study tested whether life history strategy (LHS and its intergenerational transmission could explain young adult use of common psychoactive substances. We tested a sequential structural equation model using data from the National Longitudinal Survey of Youth. During young adulthood, fast LHS explained 61% of the variance in overall liability for substance use. Faster parent LHS predicted poorer health and lesser alcohol use, greater neuroticism and cigarette smoking, but did not predict fast LHS or overall liability for substance use among young adults. Young adult neuroticism was independent of substance use controlling for fast LHS. The surprising finding of independence between parent and child LHS casts some uncertainty upon the identity of the parent and child LHS variables. Fast LHS may be the primary driver of young adult use of common psychoactive substances. However, it is possible that the young adult fast LHS variable is better defined as young adult mating competition. We discuss our findings in depth, chart out some intriguing new directions for life history research that may clarify the dimensionality of LHS and its mediation of the intergenerational transmission of substance use, and discuss implications for substance abuse prevention and treatment.

Experimental reintroduction reveals novel life-history variation in Laysan Ducks (Anas laysanensis)

Science.gov (United States)

Walters, Jeffrey R.; Reynolds, Michelle H.

2013-01-01

Subfossil remains indicate that the Laysan Duck (Anas laysanensis) formerly occurred throughout the Hawaiian archipelago, but for more than 150 years it has been confined to a single, small atoll in the northwestern chain, Laysan Island. In 2004–2005, 42 ducks were reintroduced from Laysan to Midway Atoll, where they exhibited variation in life history never observed on Laysan. On Laysan, females have never been observed to breed successfully at age 1 year and few attempt it, whereas on Midway, females routinely raised young at study; n = 21 and 19, respectively) and triple brooding has never been observed. Other novel life history on Midway included early cessation of parental care to renest. Altered life history on Midway is likely related to better feeding conditions and low population density compared with Laysan. An especially intriguing possibility is that the phenotypic plasticity observed represents exposure of hidden reaction norms evolved when the species inhabited a range of environments, but several alternative explanations exist. Future reintroductions of this species may provide opportunities to test hypotheses about mechanisms underlying phenotypic plasticity.

Life history and status of shortnose sturgeon (Acipenser brevirostrum) in the Potomac River

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Kieffer, Micah

2009-01-01

We collected the first life history information on shortnose sturgeon (Acipenser brevirostrum) in any of the rivers to Chesapeake Bay, the geographic center of the species range. In the Potomac River, two telemetry-tagged adult females used 124 km of river: a saltwater/freshwater reach at river km (rkm) 63-141 was the foraging-wintering concentration area, and one female migrated to spawn at rkm 187 in Washington, DC. The spawning migration explained the life history context of an adult captured 122 years ago in Washington, DC, supporting the idea that a natal population once lived in the river. Repeated homing migrations to foraging and wintering areas suggested the adults were residents, not transient coastal migrants. All habitats that adults need to complete life history are present in the river. The Potomac River shortnose sturgeon offers a rare opportunity to learn about the natural rebuilding of a sturgeon population.

Religious People Are Trusted Because They Are Viewed as Slow Life-History Strategists.

Science.gov (United States)

Moon, Jordan W; Krems, Jaimie Arona; Cohen, Adam B

2018-03-01

Religious people are more trusted than nonreligious people. Although most theorists attribute these perceptions to the beliefs of religious targets, religious individuals also differ in behavioral ways that might cue trust. We examined whether perceivers might trust religious targets more because they heuristically associate religion with slow life-history strategies. In three experiments, we found that religious targets are viewed as slow life-history strategists and that these findings are not the result of a universally positive halo effect; that the effect of target religion on trust is significantly mediated by the target's life-history traits (i.e., perceived reproductive strategy); and that when perceivers have direct information about a target's reproductive strategy, their ratings of trust are driven primarily by his or her reproductive strategy, rather than religion. These effects operate over and above targets' belief in moralizing gods and offer a novel theoretical perspective on religion and trust.

History of major depressive disorder prospectively predicts worse quality of life in women with breast cancer.

Science.gov (United States)

Jim, Heather S L; Small, Brent J; Minton, Susan; Andrykowski, Michael; Jacobsen, Paul B

2012-06-01

Data are scarce about whether past history of major depressive disorder in the absence of current depression places breast cancer patients at risk for worse quality of life. The current study prospectively examined quality of life during chemotherapy in breast cancer patients with a history of resolved major depressive disorder (n = 29) and no history of depression (n = 144). Women with Stages 0-II breast cancer were assessed prior to and at the completion of chemotherapy. Major depressive disorder was assessed via structured interview and quality of life with the SF-36. Patients with past major depressive disorder displayed greater declines in physical functioning relative to patients with no history of depression (p ≤ 0.01). Findings suggest that breast cancer patients with a history of resolved major depressive disorder are at increased risk for declines in physical functioning during chemotherapy relative to patients with no history of depression.

The nature and dynamics of world religions: a life-history approach.

Science.gov (United States)

Baumard, Nicolas; Chevallier, Coralie

2015-11-07

In contrast with tribal and archaic religions, world religions are characterized by a unique emphasis on extended prosociality, restricted sociosexuality, delayed gratification and the belief that these specific behaviours are sanctioned by some kind of supernatural justice. Here, we draw on recent advances in life history theory to explain this pattern of seemingly unrelated features. Life history theory examines how organisms adaptively allocate resources in the face of trade-offs between different life-goals (e.g. growth versus reproduction, exploitation versus exploration). In particular, recent studies have shown that individuals, including humans, adjust their life strategy to the environment through phenotypic plasticity: in a harsh environment, organisms tend to adopt a 'fast' strategy, pursuing smaller but more certain benefits, while in more affluent environments, organisms tend to develop a 'slow' strategy, aiming for larger but less certain benefits. Reviewing a range of recent research, we show that world religions are associated with a form of 'slow' strategy. This framework explains both the promotion of 'slow' behaviours such as altruism, self-regulation and monogamy in modern world religions, and the condemnation of 'fast' behaviours such as selfishness, conspicuous sexuality and materialism. This ecological approach also explains the diffusion pattern of world religions: why they emerged late in human history (500-300 BCE), why they are currently in decline in the most affluent societies and why they persist in some places despite this overall decline. © 2015 The Author(s).

Imitative and Direct Learning as Interacting Factors in Life History Evolution.

Science.gov (United States)

Bullinaria, John A

2017-01-01

The idea that lifetime learning can have a significant effect on life history evolution has recently been explored using a series of artificial life simulations. These involved populations of competing individuals evolving by natural selection to learn to perform well on simplified abstract tasks, with the learning consisting of identifying regularities in their environment. In reality, there is more to learning than that type of direct individual experience, because it often includes a substantial degree of social learning that involves various forms of imitation of what other individuals have learned before them. This article rectifies that omission by incorporating memes and imitative learning into revised versions of the previous approach. To do this reliably requires formulating and testing a general framework for meme-based simulations that will enable more complete investigations of learning as a factor in any life history evolution scenarios. It does that by simulating imitative information transfer in terms of memes being passed between individuals, and developing a process for merging that information with the (possibly inconsistent) information acquired by direct experience, leading to a consistent overall body of learning. The proposed framework is tested on a range of learning variations and a representative set of life history factors to confirm the robustness of the approach. The simulations presented illustrate the types of interactions and tradeoffs that can emerge, and indicate the kinds of species-specific models that could be developed with this approach in the future.

The nature and dynamics of world religions: a life-history approach

Science.gov (United States)

Baumard, Nicolas; Chevallier, Coralie

2015-01-01

In contrast with tribal and archaic religions, world religions are characterized by a unique emphasis on extended prosociality, restricted sociosexuality, delayed gratification and the belief that these specific behaviours are sanctioned by some kind of supernatural justice. Here, we draw on recent advances in life history theory to explain this pattern of seemingly unrelated features. Life history theory examines how organisms adaptively allocate resources in the face of trade-offs between different life-goals (e.g. growth versus reproduction, exploitation versus exploration). In particular, recent studies have shown that individuals, including humans, adjust their life strategy to the environment through phenotypic plasticity: in a harsh environment, organisms tend to adopt a ‘fast' strategy, pursuing smaller but more certain benefits, while in more affluent environments, organisms tend to develop a ‘slow' strategy, aiming for larger but less certain benefits. Reviewing a range of recent research, we show that world religions are associated with a form of ‘slow' strategy. This framework explains both the promotion of ‘slow' behaviours such as altruism, self-regulation and monogamy in modern world religions, and the condemnation of ‘fast' behaviours such as selfishness, conspicuous sexuality and materialism. This ecological approach also explains the diffusion pattern of world religions: why they emerged late in human history (500–300 BCE), why they are currently in decline in the most affluent societies and why they persist in some places despite this overall decline. PMID:26511055

Issues Using the Life History Calendar in Disability Research

Science.gov (United States)

Scott, Tiffany N.; Harrison, Tracie

2011-01-01

Background Overall, there is a dearth of research reporting mixed-method data collection procedures using the LHC within disability research. Objective This report provides practical knowledge on use of the life history calendar (LHC) from the perspective of a mixed-method life history study of mobility impairment situated within a qualitative paradigm. Methods In this paper the method related literature referring to the LHC was reviewed along with its epistemological underpinnings. Further, the uses of the LHC in disability research were illustrated using preliminary data from reports of disablement in Mexican American and Non-Hispanic White women with permanent mobility impairment. Results From our perspective, the LHC was most useful when approached from an interpretive paradigm when gathering data from women of varied ethnic and socioeconomic strata. While we found the LHC the most useful tool currently available for studying disablement over the life course, there were challenges associated with its use. The LHC required extensive interviewer training. In addition, large segments of time were needed for completion depending on the type of participant responses. Conclusions Researchers planning to conduct a disability study may find our experience using the LHC valuable for anticipating issues that may arise when the LHC is used in mixed-method research. PMID:22014674

Factors That Impact End-of-Life Decision Making in African Americans With Advanced Cancer

Science.gov (United States)

Campbell, Cathy L.; Williams, Ishan C.; Orr, Tamara

2013-01-01

Significance African Americans with cancer are less likely to use hospice services and more likely to die in the hospital than white patients with the same diagnosis. However, there is much that is not understood about the factors that lead African Americans to choose options for end-of-life care. Design A qualitative, descriptive design was used in this pilot study. Methods Interviews were conducted with two groups of African Americans with advanced-stage cancer (people enrolled in hospice and those who were not under hospice care). Findings End-of-life decisions were primarily guided by clinical factors, the patient-related physical, emotional, and cognitive symptoms that are sequelae of the underlying disease or medical treatments. The physician was the healthcare provider most likely to be involved in decision making with patients, family members, and caregivers. Individual factors, such as personal beliefs, influenced end-of-life decision making. Religion and spirituality were a topic in many interviews, but they did not consistently influence decision making. Discussion Future studies should include interviews with family members, caregivers, and healthcare professionals so that factors that impact end-of-life decision making can be fully described. Strategies to facilitate recruitment will need to be added to future protocols. PMID:23645999

Snake River Fall Chinook Salmon Life History Investigations, Annual Report 2008.

Energy Technology Data Exchange (ETDEWEB)

Tiffan, Kenneth F. [U.S. Geological Survey; Connor, William P. [U.S. Fish and Wildlife Service; Bellgraph, Brian J. [Pacific Northwest National Laboratory

2009-09-15

This study was initiated to provide empirical data and analyses on the dam passage timing, travel rate, survival, and life history variation of fall Chinook salmon that are produced in the Clearwater River. The area of interest for this study focuses on the lower four miles of the Clearwater River and its confluence with the Snake River because this is an area where many fish delay their seaward migration. The goal of the project is to increase our understanding of the environmental and biological factors that affect juvenile life history of fall Chinook salmon in the Clearwater River. The following summaries are provided for each of the individual chapters in this report.

End-of-life decisions for people with intellectual disabilities, an interview study with patient representatives

NARCIS (Netherlands)

Wagemans, A.M.; Schrojenstein Lantman-de Valk, H.M. van; Proot, I.M.; Metsemakers, J.; Tuffrey-Wijne, I.; Curfs, L.M.G.

2013-01-01

Background: Not much is known about the process of end-of-life decision-making for people with intellectual disabilities. Aim: To clarify the process of end-of-life decision-making for people with intellectual disabilities from the perspective of patient representatives. Design: A qualitative study

End-of-life decisions: an important theme in the care for people with intellectual disabilities.

NARCIS (Netherlands)

Wagemans, A.; Schrojenstein Lantman, H.M.J. van; Tuffrey-Wijne, I.; Widdershoven, G.; Curfs, L.M.G.

2010-01-01

BACKGROUND: While end-of-life decisions in the general population have received attention in several countries, not much is known about this in people with intellectual disabilities (IDs). Therefore, the prevalence and nature of end-of-life decisions were investigated in a Dutch centre providing

Cross-cultural Comparison of Learning in Human Hunting : Implications for Life History Evolution.

Science.gov (United States)

MacDonald, Katharine

2007-12-01

This paper is a cross-cultural examination of the development of hunting skills and the implications for the debate on the role of learning in the evolution of human life history patterns. While life history theory has proven to be a powerful tool for understanding the evolution of the human life course, other schools, such as cultural transmission and social learning theory, also provide theoretical insights. These disparate theories are reviewed, and alternative and exclusive predictions are identified. This study of cross-cultural regularities in how children learn hunting skills, based on the ethnographic literature on traditional hunters, complements existing empirical work and highlights future areas for investigation.

An Economic Model of Mortality Salience in Personal Financial Decision Making: Applications to Annuities, Life Insurance, Charitable Gifts, Estate Planning, Conspicuous Consumption, and Healthcare

Directory of Open Access Journals (Sweden)

Russell N James III

2016-12-01

Full Text Available The study of personal mortality salience and the denial of death have a long history in psychology leading to the modern field of Terror Management Theory. However, a simple consumer utility function predicts many of the outcomes identified in experimental research in this field. Further, this economic approach explains a range of otherwise unexpected financial decision-making behaviors in areas as diverse as annuities, life insurance, charitable gifts and bequests, intra-family gifts and bequests, conspicuous consumption, and healthcare. With its relevance to such a wide range of personal financial decisions, understanding the impact of mortality salience can be particularly useful to advisors in related fields.

Life-History Traits and Population Structure of Pederson Cleaner Shrimps Ancylomenes pedersoni.

Science.gov (United States)

Gilpin, Jessica A; Chadwick, Nanette E

2017-12-01

Cleaner organisms perform key functional roles in reducing rates of parasitism in marine communities. Pederson cleaner shrimps Ancylomenes pedersoni are major cleaners of reef fishes in the tropical western Atlantic and form obligate symbioses with host sea anemones. Information about their life-history traits would contribute to understanding how symbiosis impacts life-history evolution in crustaceans, but little is known about patterns of growth and reproduction in this anemone shrimp. We quantified growth, sexual reproduction, senescence, and mortality in individuals of A. pedersoni under laboratory conditions and their abundance and population size structure on coral reefs in St. Thomas, U.S. Virgin Islands. Von Bertalanffy growth curves were fitted to the data to determine age-size relationships, and the Beverton-Holt model was used to estimate mortality rates and size at maximum yield. Individuals grew rapidly when young, then slowed their growth after reaching sexual maturity at ~6 months. Individuals were gonochoric, with males attaining significantly smaller body sizes and shorter life spans than did females. Prior to death at <2 years, members of both genders exhibited senescence during which they ceased reproducing, shrank (females only), and decreased their activity levels over ~1-4 weeks. Field populations were abundant and composed mostly of juveniles during both years examined. Populations appeared to be stable but highly dynamic in terms of individuals, reaching maximum yield at 4 months of age. We conclude that obligate symbiosis with large sea anemones and cleaner mutualism with reef fishes both contribute to explaining aspects of the life history of Pederson shrimps, especially their apparent mating system of pure-search polygynandry. This life-history information also provides a scientific basis for sustainable fishery management and aquaculture of this key coral reef organism.

Evolutionary ecology of endocrine-mediated life-history variation in the garter snake Thamnophis elegans.

Science.gov (United States)

Sparkman, Amanda M; Vleck, Carol M; Bronikowski, Anne M

2009-03-01

The endocrine system plays an integral role in the regulation of key life-history traits. Insulin-like growth factor-1 (IGF-1) is a hormone that promotes growth and reproduction, and it has been implicated in the reduction of lifespan. IGF-1 is also capable of responding plastically to environmental stimuli such as resource availability and temperature. Thus pleiotropic control of life-history traits by IGF-1 could provide a mechanism for the evolution of correlated life-history traits in a new or changing environment. An ideal system in which to investigate the role of IGF-1 in life-history evolution exists in two ecotypes of the garter snake Thamnophis elegans, which derive from a single recent ancestral source but have evolved genetically divergent life-history characteristics. Snakes from meadow populations near Eagle Lake, California (USA) exhibit slower growth rates, lower annual reproductive output, and longer median adult lifespans relative to populations along the lakeshore. We hypothesized that the IGF-1 system has differentiated between these ecotypes and can account for increased growth and reproduction and reduced survival in lakeshore vs. meadow snakes. We tested for a difference in plasma IGF-1 levels in free-ranging snakes from replicate populations of each ecotype over three years. IGF-1 levels were significantly associated with adult body size, reproductive output, and season in a manner that reflects established differences in prey ecology and age/size-specific reproduction between the ecotypes. These findings are discussed in the context of theoretical expectations for a tradeoff between reproduction and lifespan that is mediated by pleiotropic endocrine mechanisms.

End-of-life decision-making and terminal sedation among very old patients.

Science.gov (United States)

De Gendt, Cindy; Bilsen, Johan; Mortier, Freddy; Vander Stichele, Robert; Deliens, Luc

2009-01-01

About half of the persons who die in developed countries are very old (aged 80 years or older) and this proportion is still rising. In general, there is little information available concerning the circumstances and quality of the end of life of this group. This study aims (1) to describe the incidence and characteristics of medical end-of-life decisions with a possible or certain life-shortening effect (ELDs) and terminal sedation among very old patients who died nonsuddenly, (2) to describe the characteristics of the preceding decision-making process, and (3) to compare this with the deaths of younger patients. A sample of 5,005 death certificates was selected from all deaths in Flanders (Belgium) in the second half of 2001 (before euthanasia was legalized). Questionnaires were mailed to the certifying physicians. Response rate was 58.9%. An ELD was made for 53.6% very old (aged 80+) patients who died nonsuddenly (vs. 63.3% for the younger patients). Use of life-ending drugs occurred among 1.1% (six times less frequently than in younger patients), with no euthanasia cases, pain and symptom alleviation with a possible life-shortening effect among 27.3% (two times less frequently), and withholding or withdrawing life-prolonging treatments among 25.2% (slightly more frequently). Terminal sedation occurred among 6.9% of the cases, two times less frequently than for the younger patients. ELDs were not often discussed with very old patients. Among competent patients this was less than compared with younger patients. ELDs are less common for very old than for younger patients. Physicians seem to have a more reluctant attitude towards the use of lethal drugs, terminal sedation and participation in decision-making when dealing with very old patients. Advance care planning should increase the involvement of very old competent and noncompetent patients in end-of-life decision-making. (c) 2008 S. Karger AG, Basel.

Family members' informal roles in end-of-life decision making in adult intensive care units.

Science.gov (United States)

Quinn, Jill R; Schmitt, Madeline; Baggs, Judith Gedney; Norton, Sally A; Dombeck, Mary T; Sellers, Craig R

2012-01-01

To support the process of effective family decision making, it is important to recognize and understand informal roles that various family members may play in the end-of-life decision-making process. To describe some informal roles consistently enacted by family members involved in the process of end-of-life decision making in intensive care units. Ethnographic study. Data were collected via participant observation with field notes and semistructured interviews on 4 intensive care units in an academic health center in the mid-Atlantic United States from 2001 to 2004. The units studied were a medical, a surgical, a burn and trauma, and a cardiovascular intensive care unit. Health care clinicians, patients, and family members. Informal roles for family members consistently observed were primary caregiver, primary decision maker, family spokesperson, out-of-towner, patient's wishes expert, protector, vulnerable member, and health care expert. The identified informal roles were part of families' decision-making processes, and each role was part of a potentially complicated family dynamic for end-of-life decision making within the family system and between the family and health care domains. These informal roles reflect the diverse responses to demands for family decision making in what is usually a novel and stressful situation. Identification and description of these informal roles of family members can help clinicians recognize and understand the functions of these roles in families' decision making at the end of life and guide development of strategies to support and facilitate increased effectiveness of family discussions and decision-making processes.

Contrasting latitudinal patterns of life-history divergence in two genera of new world thrushes (Turdinae)

Science.gov (United States)

Boyce, Andy J.; Martin, Thomas E.

2017-01-01

Several long-standing hypotheses have been proposed to explain latitudinal patterns of life-history strategies. Here, we test predictions of four such hypotheses (seasonality, food limitation, nest predation and adult survival probability) by examining life-history traits and age-specific mortality rates of several species of thrushes (Turdinae) based on field studies at temperate and tropical sites and data gathered from the literature. Thrushes in the genus Catharus showed the typical pattern of slower life-history strategies in the tropics while co-occuring Turdus thrushes differed much less across latitudes. Seasonality is a broadly accepted hypothesis for latitudinal patterns, but the lack of concordance in latitudinal patterns between co-existing genera that experience the same seasonal patterns suggests seasonality cannot fully explain latitudinal trait variation in thrushes. Nest-predation also could not explain patterns based on our field data and literature data for these two genera. Total feeding rates were similar, and per-nestling feeding rates were higher at tropical latitudes in both genera, suggesting food limitation does not explain trait differences in thrushes. Latitudinal patterns of life histories in these two genera were closely associated with adult survival probability. Thus, our data suggest that environmental influences on adult survival probability may play a particularly strong role in shaping latitudinal patterns of life-history traits.

Corticosterone and pace of life in two life-history ecotypes of the garter snake Thamnophis elegans.

Science.gov (United States)

Palacios, Maria G; Sparkman, Amanda M; Bronikowski, Anne M

2012-02-01

Glucocorticoids are main candidates for mediating life-history trade-offs by regulating the balance between current reproduction and survival. It has been proposed that slow-living organisms should show higher stress-induced glucocorticoid levels that favor self-maintenance rather than current reproduction when compared to fast-living organisms. We tested this hypothesis in replicate populations of two ecotypes of the garter snake (Thamnophis elegans) that exhibit slow and fast pace of life strategies. We subjected free-ranging snakes to a capture-restraint protocol and compared the stress-induced corticosterone levels between slow- and fast-living snakes. We also used a five-year dataset to assess whether baseline corticosterone levels followed the same pattern as stress-induced levels in relation to pace of life. In accordance with the hypothesis, slow-living snakes showed higher stress-induced corticosterone levels than fast-living snakes. Baseline corticosterone levels showed a similar pattern with ecotype, although differences depended on the year of study. Overall, however, levels of glucocorticoids are higher in slow-living than fast-living snakes, which should favor self-maintenance and survival at the expense of current reproduction. The results of the present study are the first to relate glucocorticoid levels and pace of life in a reptilian system and contribute to our understanding of the physiological mechanisms involved in life-history evolution. Copyright © 2011 Elsevier Inc. All rights reserved.

Population transcriptomics of life-history variation in the genus Salmo

DEFF Research Database (Denmark)

Giger, T.; Excoffier, L.; Amstutz, U.

2008-01-01

with physiological changes that are likely to be involved in preadaptations to seawater in anadromous populations of the genus Salmo, one of which was identified to encode for nucleophosmin 1. Our findings thus provide new molecular insights into salmonid life-history variation, opening new perspectives in the study......In this study, we demonstrate the power of applying complementary DNA (cDNA) microarray technology to identifying candidate loci that exhibit subtle differences in expression levels associated with a complex trait in natural populations of a nonmodel organism. Using a highly replicated experimental...... design involving 180 cDNA microarray experiments, we measured gene-expression levels from 1098 transcript probes in 90 individuals originating from six brown trout (Salmo trutta) and one Atlantic salmon (Salmo salar) population, which follow either a migratory or a sedentary life history. We identified...

History of Major Depressive Disorder Prospectively Predicts Worse Quality of Life in Women with Breast Cancer

Science.gov (United States)

Small, Brent J.; Minton, Susan; Andrykowski, Michael; Jacobsen, Paul B.

2012-01-01

Background Data are scarce about whether past history of major depressive disorder in the absence of current depression places breast cancer patients at risk for worse quality of life. Purpose The current study prospectively examined quality of life during chemotherapy in breast cancer patients with a history of resolved major depressive disorder (n=29) and no history of depression (n=144). Methods Women with Stages 0–II breast cancer were assessed prior to and at the completion of chemotherapy. Major depressive disorder was assessed via structured interview and quality of life with the SF-36. Results Patients with past major depressive disorder displayed greater declines in physical functioning relative to patients with no history of depression (p≤0.01). Conclusions Findings suggest that breast cancer patients with a history of resolved major depressive disorder are at increased risk for declines in physical functioning during chemotherapy relative to patients with no history of depression. PMID:22167580

A Brief History of Family Life Education in Romania

Science.gov (United States)

Momanu, Mariana; Popa, Nicoleta Laura; Samoila, Magda-Elena

2018-01-01

Starting from the state of conceptual diversity, semantic ambiguity, and poor connection of family life education practices to current policies and theoretical models in Romania, our study aims at understanding the underlying meanings of these issues by recourse to the history of approaches in the field. To this purpose, we carried out a…

Life-history diversity and its importance to population stability and persistence of a migratory fish: steelhead in two large North American watersheds.

Science.gov (United States)

Moore, Jonathan W; Yeakel, Justin D; Peard, Dean; Lough, Jeff; Beere, Mark

2014-09-01

Life-history strategies can buffer individuals and populations from environmental variability. For instance, it is possible that asynchronous dynamics among different life histories can stabilize populations through portfolio effects. Here, we examine life-history diversity and its importance to stability for an iconic migratory fish species. In particular, we examined steelhead (Oncorhynchus mykiss), an anadromous and iteroparous salmonid, in two large, relatively pristine, watersheds, the Skeena and Nass, in north-western British Columbia, Canada. We synthesized life-history information derived from scales collected from adult steelhead (N = 7227) in these watersheds across a decade. These migratory fishes expressed 36 different manifestations of the anadromous life-history strategy, with 16 different combinations of freshwater and marine ages, 7·6% of fish performing multiple spawning migrations, and up to a maximum of four spawning migrations per lifetime. Furthermore, in the Nass watershed, various life histories were differently prevalent through time - three different life histories were the most prevalent in a given year, and no life history ever represented more than 45% of the population. These asynchronous dynamics among life histories decreased the variability of numerical abundance and biomass of the aggregated population so that it was > 20% more stable than the stability of the weighted average of specific life histories: evidence of a substantial portfolio effect. Year of ocean entry was a key driver of dynamics; the median correlation coefficient of abundance of life histories that entered the ocean the same year was 2·5 times higher than the median pairwise coefficient of life histories that entered the ocean at different times. Simulations illustrated how different elements of life-history diversity contribute to stability and persistence of populations. This study provides evidence that life-history diversity can dampen fluctuations in

Modelling in life insurance a management perspective

CERN Document Server

Norberg, Ragnar; Planchet, Frédéric

2016-01-01

Focussing on life insurance and pensions, this book addresses various aspects of modelling in modern insurance: insurance liabilities; asset-liability management; securitization, hedging, and investment strategies. With contributions from internationally renowned academics in actuarial science, finance, and management science and key people in major life insurance and reinsurance companies, there is expert coverage of a wide range of topics, for example: models in life insurance and their roles in decision making; an account of the contemporary history of insurance and life insurance mathematics; choice, calibration, and evaluation of models; documentation and quality checks of data; new insurance regulations and accounting rules; cash flow projection models; economic scenario generators; model uncertainty and model risk; model-based decision-making at line management level; models and behaviour of stakeholders. With author profiles ranging from highly specialized model builders to decision makers at chief ex...

The rational choice model in family decision making at the end of life.

Science.gov (United States)

Karasz, Alison; Sacajiu, Galit; Kogan, Misha; Watkins, Liza

2010-01-01

Most end-of-life decisions are made by family members. Current ethical guidelines for family decision making are based on a hierarchical model that emphasizes the patient's wishes over his or her best interests. Evidence suggests that the model poorly reflects the strategies and priorities of many families. Researchers observed and recorded 26 decision-making meetings between hospital staff and family members. Semi-structured follow-up interviews were conducted. Transcriptions were analyzed using qualitative techniques. For both staff and families, consideration of a patient's best interests generally took priority over the patient's wishes. Staff generally introduced discussion of the patient's wishes for rhetorical purposes, such as persuasion. Competing moral frameworks, which de-emphasized the salience of patients' autonomy and "right to choose," played a role in family decision making. The priority given to the patients' wishes in the hierarchical model does not reflect the priorities of staff and families in making decisions about end-of-life care.

Life history strategy and the HEXACO personality dimensions

OpenAIRE

Manson, JH

2015-01-01

Although several studies have linked Life History Strategy (LHS) variation with variation in the Five Factor Model personality dimensions, no published research has explored the relationship of LHS to the HEXACO personality dimensions. The theoretically expected relationship of the HEXACO Emotionality factor to LHS is unclear. The results of two studies (N = 641) demonstrated that LHS indicators form part of a factor along with HEXACO Extraversion, Agreeableness, Conscientiousness, and (margi...

Life-history strategies associated with local population variability confer regional stability.

Science.gov (United States)

Pribil, Stanislav; Houlahan, Jeff E

2003-07-07

A widely held ecological tenet is that, at the local scale, populations of K-selected species (i.e. low fecundity, long lifespan and large body size) will be less variable than populations of r-selected species (i.e. high fecundity, short lifespan and small body size). We examined the relationship between long-term population trends and life-history attributes for 185 bird species in the Czech Republic and found that, at regional spatial scales and over moderate temporal scales (100-120 years), K-selected bird species were more likely to show both large increases and decreases in population size than r-selected species. We conclude that life-history attributes commonly associated with variable populations at the local scale, confer stability at the regional scale.

The Mass-Longevity Triangle: Pareto Optimality and the Geometry of Life-History Trait Space

Science.gov (United States)

Szekely, Pablo; Korem, Yael; Moran, Uri; Mayo, Avi; Alon, Uri

2015-01-01

When organisms need to perform multiple tasks they face a fundamental tradeoff: no phenotype can be optimal at all tasks. This situation was recently analyzed using Pareto optimality, showing that tradeoffs between tasks lead to phenotypes distributed on low dimensional polygons in trait space. The vertices of these polygons are archetypes—phenotypes optimal at a single task. This theory was applied to examples from animal morphology and gene expression. Here we ask whether Pareto optimality theory can apply to life history traits, which include longevity, fecundity and mass. To comprehensively explore the geometry of life history trait space, we analyze a dataset of life history traits of 2105 endothermic species. We find that, to a first approximation, life history traits fall on a triangle in log-mass log-longevity space. The vertices of the triangle suggest three archetypal strategies, exemplified by bats, shrews and whales, with specialists near the vertices and generalists in the middle of the triangle. To a second approximation, the data lies in a tetrahedron, whose extra vertex above the mass-longevity triangle suggests a fourth strategy related to carnivory. Each animal species can thus be placed in a coordinate system according to its distance from the archetypes, which may be useful for genome-scale comparative studies of mammalian aging and other biological aspects. We further demonstrate that Pareto optimality can explain a range of previous studies which found animal and plant phenotypes which lie in triangles in trait space. This study demonstrates the applicability of multi-objective optimization principles to understand life history traits and to infer archetypal strategies that suggest why some mammalian species live much longer than others of similar mass. PMID:26465336

The Mass-Longevity Triangle: Pareto Optimality and the Geometry of Life-History Trait Space.

Science.gov (United States)

Szekely, Pablo; Korem, Yael; Moran, Uri; Mayo, Avi; Alon, Uri

2015-10-01

When organisms need to perform multiple tasks they face a fundamental tradeoff: no phenotype can be optimal at all tasks. This situation was recently analyzed using Pareto optimality, showing that tradeoffs between tasks lead to phenotypes distributed on low dimensional polygons in trait space. The vertices of these polygons are archetypes--phenotypes optimal at a single task. This theory was applied to examples from animal morphology and gene expression. Here we ask whether Pareto optimality theory can apply to life history traits, which include longevity, fecundity and mass. To comprehensively explore the geometry of life history trait space, we analyze a dataset of life history traits of 2105 endothermic species. We find that, to a first approximation, life history traits fall on a triangle in log-mass log-longevity space. The vertices of the triangle suggest three archetypal strategies, exemplified by bats, shrews and whales, with specialists near the vertices and generalists in the middle of the triangle. To a second approximation, the data lies in a tetrahedron, whose extra vertex above the mass-longevity triangle suggests a fourth strategy related to carnivory. Each animal species can thus be placed in a coordinate system according to its distance from the archetypes, which may be useful for genome-scale comparative studies of mammalian aging and other biological aspects. We further demonstrate that Pareto optimality can explain a range of previous studies which found animal and plant phenotypes which lie in triangles in trait space. This study demonstrates the applicability of multi-objective optimization principles to understand life history traits and to infer archetypal strategies that suggest why some mammalian species live much longer than others of similar mass.

Life history trade-offs and relaxed selection can decrease bacterial virulence in environmental reservoirs.

Directory of Open Access Journals (Sweden)

Lauri Mikonranta

Full Text Available Pathogen virulence is usually thought to evolve in reciprocal selection with the host. While this might be true for obligate pathogens, the life histories of opportunistic pathogens typically alternate between within-host and outside-host environments during the infection-transmission cycle. As a result, opportunistic pathogens are likely to experience conflicting selection pressures across different environments, and this could affect their virulence through life-history trait correlations. We studied these correlations experimentally by exposing an opportunistic bacterial pathogen Serratia marcescens to its natural protist predator Tetrahymena thermophila for 13 weeks, after which we measured changes in bacterial traits related to both anti-predator defence and virulence. We found that anti-predator adaptation (producing predator-resistant biofilm caused a correlative attenuation in virulence. Even though the direct mechanism was not found, reduction in virulence was most clearly connected to a predator-driven loss of a red bacterial pigment, prodigiosin. Moreover, life-history trait evolution was more divergent among replicate populations in the absence of predation, leading also to lowered virulence in some of the 'predator absent' selection lines. Together these findings suggest that the virulence of non-obligatory, opportunistic bacterial pathogens can decrease in environmental reservoirs through life history trade-offs, or random accumulation of mutations that impair virulence traits under relaxed selection.

Herbivore-mediated ecological costs of reproduction shape the life history of an iteroparous plant.

Science.gov (United States)

Miller, Tom E X; Tenhumberg, Brigitte; Louda, Svata M

2008-02-01

Plant reproduction yields immediate fitness benefits but can be costly in terms of survival, growth, and future fecundity. Life-history theory posits that reproductive strategies are shaped by trade-offs between current and future fitness that result from these direct costs of reproduction. Plant reproduction may also incur indirect ecological costs if it increases susceptibility to herbivores. Yet ecological costs of reproduction have received little empirical attention and remain poorly integrated into life-history theory. Here, we provide evidence for herbivore-mediated ecological costs of reproduction, and we develop theory to examine how these costs influence plant life-history strategies. Field experiments with an iteroparous cactus (Opuntia imbricata) indicated that greater reproductive effort (proportion of meristems allocated to reproduction) led to greater attack by a cactus-feeding insect (Narnia pallidicornis) and that damage by this herbivore reduced reproductive success. A dynamic programming model predicted strongly divergent optimal reproductive strategies when ecological costs were included, compared with when these costs were ignored. Meristem allocation by cacti in the field matched the optimal strategy expected under ecological costs of reproduction. The results indicate that plant reproductive allocation can strongly influence the intensity of interactions with herbivores and that associated ecological costs can play an important selective role in the evolution of plant life histories.

The ecology of life history evolution : genes, individuals and populations

NARCIS (Netherlands)

Visser, M.E.

2013-01-01

Natural selection shapes the life histories of organisms. The ecological interactions of these organisms with their biotic and abiotic environment shape the selection pressure on their phenotypes while their genetics determine how fast this selection leads to adaptation to their environment. The

Life history plasticity of a tropical seabird in response to El Niño anomalies during early life.

Directory of Open Access Journals (Sweden)

Sergio Ancona

Full Text Available Food shortage and other challenges associated with El Niño Southern Oscillation (ENSO experienced early in life may have long-term impacts on life history traits, but these potential impacts remain virtually unexplored. By monitoring 2556 blue-footed boobies from 11 cohorts, we showed that birds facing warm water ENSO conditions (and probably low food availability in the natal year were underweight at fledging, recruited earlier and bred less frequently, but showed no deficit in longevity or breeding success over the first 10 years. Life history impacts of ENSO were substantial when experienced in the prenatal year, the natal year, or the second year of life, and absent when experienced in the third year of life, implying that harsh conditions have greater effects when experienced earlier in life. Sexual differences in impacts depended on the age when warm water conditions were experienced: pre-natal and natal experience, respectively, induced early recruitment and influenced the relationship between age and laying date only in females, whereas second year experience reduced total breeding success only of males. Most surprising were positive transgenerational impacts in females: daughters of females that experienced ENSO conditions in their natal year showed improved breeding success. Developmental plasticity of boobies thus enables them to largely neutralize potential long-term impacts of harsh climatic conditions experienced early in life.

Life history plasticity of a tropical seabird in response to El Niño anomalies during early life.

Science.gov (United States)

Ancona, Sergio; Drummond, Hugh

2013-01-01

Food shortage and other challenges associated with El Niño Southern Oscillation (ENSO) experienced early in life may have long-term impacts on life history traits, but these potential impacts remain virtually unexplored. By monitoring 2556 blue-footed boobies from 11 cohorts, we showed that birds facing warm water ENSO conditions (and probably low food availability) in the natal year were underweight at fledging, recruited earlier and bred less frequently, but showed no deficit in longevity or breeding success over the first 10 years. Life history impacts of ENSO were substantial when experienced in the prenatal year, the natal year, or the second year of life, and absent when experienced in the third year of life, implying that harsh conditions have greater effects when experienced earlier in life. Sexual differences in impacts depended on the age when warm water conditions were experienced: pre-natal and natal experience, respectively, induced early recruitment and influenced the relationship between age and laying date only in females, whereas second year experience reduced total breeding success only of males. Most surprising were positive transgenerational impacts in females: daughters of females that experienced ENSO conditions in their natal year showed improved breeding success. Developmental plasticity of boobies thus enables them to largely neutralize potential long-term impacts of harsh climatic conditions experienced early in life.

Comparing life history characteristics of Lake Michigan’s naturalized and stocked Chinook Salmon

Science.gov (United States)

Kerns, Janice A; Rogers, Mark W.; Bunnell, David B.; Claramunt, Randall M.; Collingsworth, Paris D.

2016-01-01

Lake Michigan supports popular fisheries for Chinook Salmon Oncorhynchus tshawytscha that have been sustained by stocking since the late 1960s. Natural recruitment of Chinook Salmon in Lake Michigan has increased in the past few decades and currently contributes more than 50% of Chinook Salmon recruits. We hypothesized that selective forces differ for naturalized populations born in the wild and hatchery populations, resulting in divergent life history characteristics with implications for Chinook Salmon population production and the Lake Michigan fishery. First, we conducted a historical analysis to determine if life history characteristics changed through time as the Chinook Salmon population became increasingly naturalized. Next, we conducted a 2-year field study of naturalized and hatchery stocked Chinook Salmon spawning populations to quantify differences in fecundity, egg size, timing of spawning, and size at maturity. In general, our results did not indicate significant life history divergence between naturalized and hatchery-stocked Chinook Salmon populations in Lake Michigan. Although historical changes in adult sex ratio were correlated with the proportion of naturalized individuals, changes in weight at maturity were better explained by density-dependent factors. The field study revealed no divergence in fecundity, timing of spawning, or size at maturity, and only small differences in egg size (hatchery > naturalized). For the near future, our results suggest that the limited life history differences observed between Chinook Salmon of naturalized and hatchery origin will not lead to large differences in characteristics important to the dynamics of the population or fishery.

Wind Power Project Repowering: Financial Feasibility, Decision Drivers, and Supply Chain Effects

Energy Technology Data Exchange (ETDEWEB)

Lantz, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Leventhal, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Baring-Gould, Ian [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2013-12-01

As wind power facilities age, project owners are faced with plant end of life decisions. This report is intended to inform policymakers and the business community regarding the history, opportunities, and challenges associated with plant end of life actions, in particular repowering. Specifically, the report details the history of repowering, examines the plant age at which repowering becomes financially attractive, and estimates the incremental market investment and supply chain demand that might result from future U.S. repowering activities.

[Quality of life or life expectancy? Criteria and sources of information in the decision-making of patients undergoing aortic valve surgery].

Science.gov (United States)

Schmied, Wolfram; Barnick, Saskia; Heimann, Dierk; Schäfers, Hans-Joachim; Köllner, Volker

2015-01-01

Physicians are expected to involve patients adequately in the decision-making process prior to surgery. To this end, it is essential to have knowledge about the potential reasons for such a decision. In this study we investigated which information sources and decision criteria are important to patients prior to aortic valve surgery. A consecutive sample of 468 patients (70.1%m, aged 66.9±14.2 years) was examined 2 years after aortic valve replacement or reconstruction with a self-developed questionnaire. Preoperative discussion with a cardiologist or a cardiac surgeon was the information source patients used most frequently and felt to be the most helpful. The most important decision criterion was quality of life, followed by life expectancy and likelihood of reoperation. Two years postoperatively, 97.3% of the patients were satisfied with their decision. Preoperative counseling by a physician plays an essential role in the decision-making process prior to cardiac surgery. Patients want to be involved in decision-making, though they do not want to bear the full responsibility.

Discussing End-of-Life Decisions in a Clinical Ethics Committee: An Interview Study of Norwegian Doctors' Experience.

Science.gov (United States)

Bahus, Marianne K; Førde, Reidun

2016-09-01

With disagreement, doubts, or ambiguous grounds in end-of-life decisions, doctors are advised to involve a clinical ethics committee (CEC). However, little has been published on doctors' experiences with discussing an end-of-life decision in a CEC. As part of the quality assurance of this work, we wanted to find out if clinicians have benefited from discussing end-of-life decisions in CECs and why. We will disseminate some Norwegian doctors' experiences when discussing end-of-life decisions in CECs, based on semi-structured interviews with fifteen Norwegian physicians who had brought an end-of-life decision case to a CEC. Almost half of the cases involved conflicts with the patients' relatives. In a majority of the cases, there was uncertainty about what would be the ethically preferable solution. Reasons for referring the case to the CEC were to get broader illumination of the case, to get perspective from people outside the team, to get advice, or to get moral backing on a decision already made. A great majority of the clinicians reported an overall positive experience with the CECs' discussions. In cases where there was conflict, the clinicians reported less satisfaction with the CECs' discussions. The study shows that most doctors who have used a CEC in an end-of-life decision find it useful to have ethical and/or legal aspects illuminated, and to have the dilemma scrutinized from a new perspective. A systematic discussion seems to be significant to the clinicians.

Euthanasia and other end-of-life decisions: a mortality follow-back study in Belgium

Directory of Open Access Journals (Sweden)

Bossuyt Nathalie

2009-03-01

Full Text Available Abstract Background This study compares prevalence and types of medical end-of-life decisions between the Dutch-speaking and French-speaking communities of Belgium. This is the first nationwide study that can make these comparisons and the first measurement after implementation of the euthanasia law (2002. Methods We performed a mortality follow-back study in 2005–2006. Data were collected via the nationwide Sentinel Network of General Practitioners, an epidemiological surveillance system representative of all Belgian GPs. Weekly, all GPs reported the medical end-of-life decisions among all non-sudden deaths of patients in their practice. We compared the northern Dutch-speaking (60% and southern French-speaking communities (40% controlling for population differences. Results We analysed 1690 non-sudden deaths. An end-of-life decision with possible life-shortening effect was made in 50% of patients in the Dutch-speaking community and 41% of patients in the French-speaking community (OR 1.4; 95%CI, 1.2 to 1.8. Continuous deep sedation until death occurred in 8% and 15% respectively (OR 0.5; 95%CI, 0.4 to 0.7. Community differences regarding the prevalence of euthanasia or physician-assisted suicide were not significant. Community differences were more present among home/care home than among hospital deaths: non-treatment decisions with explicit life-shortening intention were made more often in the Dutch-speaking than in the French-speaking community settings (OR 2.2; 95%CI, 1.2 to 3.9; while continuous deep sedation occurred less often in the Dutch-speaking community settings (OR 0.5; 95%CI, 0.3 to 0.9. Conclusion Even though legal and general healthcare systems are the same for the whole country, there are considerable variations between the communities in type and prevalence of certain end-of-life decisions, even after controlling for population differences.

From metamorphosis to maturity in complex life cycles: equal performance of different juvenile life history pathways.

Science.gov (United States)

Schmidt, Benedikt R; Hödl, Walter; Schaub, Michael

2012-03-01

Performance in one stage of a complex life cycle may affect performance in the subsequent stage. Animals that start a new stage at a smaller size than conspecifics may either always remain smaller or they may be able to "catch up" through plasticity, usually elevated growth rates. We study how size at and date of metamorphosis affected subsequent performance in the terrestrial juvenile stage and lifetime fitness of spadefoot toads (Pelobates fuscus). We analyzed capture-recapture data of > 3000 individuals sampled during nine years with mark-recapture models to estimate first-year juvenile survival probabilities and age-specific first-time breeding probabilities of toads, followed by model selection to assess whether these probabilities were correlated with size at and date of metamorphosis. Males attained maturity after two years, whereas females reached maturity 2-4 years after metamorphosis. Age at maturity was weakly correlated with metamorphic traits. In both sexes, first-year juvenile survival depended positively on date of metamorphosis and, in males, also negatively on size at metamorphosis. In males, toads that metamorphosed early at a small size had the highest probability to reach maturity. However, because very few toadlets metamorphosed early, the vast majority of male metamorphs had a very similar probability to reach maturity. A matrix projection model constructed for females showed that different juvenile life history pathways resulted in similar lifetime fitness. We found that the effects of date of and size at metamorphosis on different juvenile traits cancelled each other out such that toads that were small or large at metamorphosis had equal performance. Because the costs and benefits of juvenile life history pathways may also depend on population fluctuations, ample phenotypic variation in life history traits may be maintained.

Contributions of dynamic environmental signals during life-cycle transitions to early life-history traits in lodgepole pine (Pinus contorta Dougl.)

Science.gov (United States)

Liu, Yang; Wang, Tongli; El-Kassaby, Yousry A.

2016-05-01

Environmental signals are important triggers in the life-cycle transitions and play a crucial role in the life-history evolution. Yet very little is known about the leading ecological factors contributing to the variations of life-history traits in perennial plants. This paper explores both the causes and consequences for the evolution of life-history traits (i.e., seed dormancy and size) in lodgepole pine (Pinus contorta Dougl.) across British Columbia (B.C.), Canada. We selected 83 logepole pine populations covering 22 ecosystem zones of B.C. and through their geographic coordinate, 197 climatic variables were generated accordingly for the reference (1961-1990) and future (2041-2070) periods. We found that dynamic climatic variables rather than constant geographic variables are the true environmental driving forces in seed dormancy and size variations and thus provide reliable predictors in response to global climate change. Evapotranspiration and precipitation in the plant-to-seed chronology are the most critical climate variables for seed dormancy and size variations, respectively. Hence, we predicted that levels of seed dormancy in lodgepole pine would increase across large tracts of B.C. in 2050s. Winter-chilling is able to increase the magnitude of life-history plasticity and lower the bet-hedge strategy in the seed-to-plant transition; however, winter-chilling is likely to be insufficient in the north of 49° N in 2050s, which may delay germination while unfavorable conditions during dry summers may result in adverse consequences in the survival of seedlings owing to extended germination span. These findings provide useful information to studies related to assessments of seed transfer and tree adaptation.

Life History Strategy and Young Adult Substance Use

OpenAIRE

George B. Richardson; Ching-Chen Chen; Chia-Liang Dai; Patrick H. Hardesty; Christopher M. Swoboda

2014-01-01

This study tested whether life history strategy (LHS) and its intergenerational transmission could explain young adult use of common psychoactive substances. We tested a sequential structural equation model using data from the National Longitudinal Survey of Youth. During young adulthood, fast LHS explained 61% of the variance in overall liability for substance use. Faster parent LHS predicted poorer health and lesser alcohol use, greater neuroticism and cigarette smoking, but did not predict...

Supporting End of Life Decision Making: Case Studies of Relational Closeness in Supported Decision Making for People with Severe or Profound Intellectual Disability

Science.gov (United States)

Watson, Joanne; Wilson, Erin; Hagiliassis, Nick

2017-01-01

Background: The United Nations Convention on the Rights of Persons with Disabilities (UNCRPD) promotes the use of supported decision making in lieu of substitute decision making. To date, there has been a lack of focus on supported decision making for people with severe or profound intellectual disability, including for end of life decisions.…

Patient-generated aspects in oral rehabilitation decision making I. Comparison of traditional history taking and an individual systematic interview method

DEFF Research Database (Denmark)

Øzhayat, Esben Boeskov; Gotfredsen, Klaus; Elverdam, Beth

2009-01-01

it with a traditional history taking, in generating information to be used in decision making in oral rehabilitation. Fifty-seven participants in need of oral rehabilitation were enrolled in the study. The participants underwent a traditional history taking and were interviewed using the SEIQoL-DW method. The SEIQo......Decision making in oral rehabilitation is often based on diagnoses related to impairment of different oral functions. In making the decision when to treat, the dentist must work in cooperation with the patient. By incorporating patient-generated aspects into the decision making process, the dentist...... percentage of the participants were positive towards the use of the SEIQoL-DW method in their treatment planning. The SEIQoL-DW was considered to be a viable tool for decision making in oral rehabilitation....

Climatic and geographic predictors of life history variation in Eastern Massasauga (Sistrurus catenatus: A range-wide synthesis.

Directory of Open Access Journals (Sweden)

Eric T Hileman

Full Text Available Elucidating how life history traits vary geographically is important to understanding variation in population dynamics. Because many aspects of ectotherm life history are climate-dependent, geographic variation in climate is expected to have a large impact on population dynamics through effects on annual survival, body size, growth rate, age at first reproduction, size-fecundity relationship, and reproductive frequency. The Eastern Massasauga (Sistrurus catenatus is a small, imperiled North American rattlesnake with a distribution centered on the Great Lakes region, where lake effects strongly influence local conditions. To address Eastern Massasauga life history data gaps, we compiled data from 47 study sites representing 38 counties across the range. We used multimodel inference and general linear models with geographic coordinates and annual climate normals as explanatory variables to clarify patterns of variation in life history traits. We found strong evidence for geographic variation in six of nine life history variables. Adult female snout-vent length and neonate mass increased with increasing mean annual precipitation. Litter size decreased with increasing mean temperature, and the size-fecundity relationship and growth prior to first hibernation both increased with increasing latitude. The proportion of gravid females also increased with increasing latitude, but this relationship may be the result of geographically varying detection bias. Our results provide insights into ectotherm life history variation and fill critical data gaps, which will inform Eastern Massasauga conservation efforts by improving biological realism for models of population viability and climate change.

Fracture history in osteoporosis: risk factors and its effect on quality of life.

Science.gov (United States)

Kuru, Pınar; Akyüz, Gülseren; Cerşit, Hülya Peynirci; Çelenlioğlu, Alp Eren; Cumhur, Ahmet; Biricik, Şefikcan; Kozan, Seda; Gökşen, Aylin; Özdemir, Mikail; Lüleci, Emel

2014-12-01

Fractures are one of the main outcomes in osteoporosis and have an important effect on the general health status. The purpose of this study was to determine the effect of major fracture history on quality of life. We also investigated the important risk factors and their effect on bone mineral density and fracture history. Cross-sectional study. We recruited 105 patients who were admitted to an osteoporosis outpatient clinic. Medical history, family history, calcium intake, physical activity level and biochemical tests were evaluated. Lumbar spine and femur neck bone mineral density were measured. The Qualeffo-41 questionnaire was also used for evaluating quality of life. The average age of the 105 patients included in the study was 56.04±13.73 and 89% of them were post-menopausal women. The average body mass index was 26.84±5.99, which means that the women were overweight. Also, 48.5% of the patients were diagnosed with osteoporosis and 51.5% of them were diagnosed as low bone density. A total of 34 patients had a fracture history with minor trauma and some of the patients had more than one fracture (12 ankle and foot, 10 forearm, 9 vertebral, 4 hand, 3 hip, 2 rib, 1 tibial). When the patients with and without fracture history were compared, the mean Qualeffo-41 score in patients with fracture was 43.85±2.57 and in the non-fracture group was 36.27±2.01. Forearm, ankle and foot fractures can be commonly seen in osteoporosis patients with fracture history. We suggest that it is important to recognise osteoporosis prior to first fracture and disease-specific quality of life assessment should be done.

Fracture History in Osteoporosis: Risk Factors and its Effect on Quality of Life

Directory of Open Access Journals (Sweden)

Pınar Kuru

2014-12-01

Full Text Available Background: Fractures are one of the main outcomes in osteoporosis and have an important effect on the general health status. Aims: The purpose of this study was to determine the effect of major fracture history on quality of life. We also investigated the important risk factors and their effect on bone mineral density and fracture history. Study Design: Cross-sectional study. Methods: We recruited 105 patients who were admitted to an osteoporosis outpatient clinic. Medical history, family history, calcium intake, physical activity level and biochemical tests were evaluated. Lumbar spine and femur neck bone mineral density were measured. The Qualeffo- 41 questionnaire was also used for evaluating quality of life. Results: The average age of the 105 patients included in the study was 56.04±13.73 and 89% of them were post-menopausal women. The average body mass index was 26.84±5.99, which means that the women were overweight. Also, 48.5% of the patients were diagnosed with osteoporosis and 51.5% of them were diagnosed as low bone density. A total of 34 patients had a fracture history with minor trauma and some of the patients had more than one fracture (12 ankle and foot, 10 forearm, 9 vertebral, 4 hand, 3 hip, 2 rib, 1 tibial. When the patients with and without fracture history were compared, the mean Qualeffo-41 score in patients with fracture was 43.85±2.57 and in the non-fracture group was 36.27±2.01. Conclusion: Forearm, ankle and foot fractures can be commonly seen in osteoporosis patients with fracture history. We suggest that it is important to recognise osteoporosis prior to first fracture and disease-specific quality of life assessment should be done.

Product Life Cycle concept use and application by marketing decision-makers in small South African organisations

Directory of Open Access Journals (Sweden)

F. J. Herbst

2003-12-01

Full Text Available The purpose of the study was to test the underlying theory of the product life cycle concept with the primary objective of establishing what the use and practical value of the product life cycle concept is in making marketing decisions in small manufacturing and dealer organisations in Gauteng. The main focus was to test the ability of marketing decision-makers in these small organisations to associate their application and use of the product life cycle concept with Kotler's assumptions on marketing characteristics, described marketing objectives and proposed marketing strategies. A major finding was that small organisations tended to display a marketing knowledge level with the existing marketing theory. Another important conclusion of the study was that the current product life cycle concept theory needs to be broadened to include strategies on the expanded marketing mix. Apart from the different use and application by marketing decision-makers in small organisations in South Africa the product life cycle concept theory has potential as a strategic tool and a high likelihood for its future use as a marketing decision-making instrument.

Is patient autonomy a critical determinant of quality of life in Korea? End-of-life decision making from the perspective of the patient.

Science.gov (United States)

Mo, Ha Na; Shin, Dong Wook; Woo, Jae Ha; Choi, Jin Young; Kang, Jina; Baik, Young Ji; Huh, Yu Rae; Won, Joo Hee; Park, Myung Hee; Cho, Sang Hee

2012-04-01

We aimed to investigate the current practice of the involvement in decision making from the perspectives of terminal cancer patients, and to explore its possible associations with quality of life and quality of death in Korea. A multi-center, cross-sectional survey was performed on 93 terminal cancer patients. The questionnaire solicited their opinions regarding participation in treatment decision making, as well as quality of life (European Organization for Research and Treatment of Cancer Quality-of-Life Questionnaire for Palliative Care) and quality of death (Good Death Inventory-Patient Version). A total of 78.5% of the patients had awareness of their terminal status, while 21.5% did not; 42.4% stated that they knew their condition and shared the decision-making responsibility with the medical staff and their family, while 21.7% made decisions on their own, and 35.9% left the decision-making responsibility to others. Patients who were aware of their illness and who actively participated in the decision making did not score higher than others on outcome measures of quality of life and quality of death. Moreover, the former even showed lower scores in some domains, including the 'physical and psychological comfort' (4.99 versus 5.61, p = 0.03), 'environmental comfort' (5.51 versus 6.04, p = 0.08), and 'emotional functioning' (55.70 versus 71.01, p = 0.06). in Korea, patient autonomy is not a universally accepted value from the perspectives of terminal cancer patients, nor is patient involvement in decision making always conducive to high quality of life or quality of death. The level of information and the pace at which it is provided should be tailored to each individual's ability, preference, need, and culture.

Transgenerational plasticity in the sea: context-dependent maternal effects across the life history.

Science.gov (United States)

Marshall, Dustin J

2008-02-01

Maternal effects can have dramatic influences on the phenotype of offspring. Maternal effects can act as a conduit by which the maternal environment negatively affects offspring fitness, but they can also buffer offspring from environmental change by altering the phenotype of offspring according to local environmental conditions and as such, are a form of transgenerational plasticity. The benefits of maternal effects can be highly context dependent, increasing performance in one life-history stage but reducing it in another. While maternal effects are increasingly well understood in terrestrial systems, studies in the marine environment are typically restricted to a single, early life-history stage. Here, I examine the role of maternal effects across the life history of the bryozoan Bugula neritina. I exposed maternal colonies to a common pollution stress (copper) in the laboratory and then placed them in the field for one week to brood offspring. I then examined the resistance of offspring to copper from toxicant-exposed and toxicant-naïve mothers and found that offspring from toxicant-exposed mothers were larger, more dispersive, and more resistant to copper stress than offspring from naïve mothers. However, maternal exposure history had pervasive, negative effects on the post-metamorphic performance (particularly survival) of offspring: offspring from toxicant-exposed mothers had poorer performance after six weeks in the field, especially when facing high levels of intraspecific competition. Maternal experience can have complex effects on offspring phenotype, enhancing performance in one life-history stage while decreasing performance in another. The context-dependent costs and benefits associated with maternally derived pollution resistance may account for why such resistance is induced rather than continually expressed: mothers must balance the benefits of producing pollution-resistant larvae with the costs of producing poorer performing adults (in the

Debkiss or the quest for the simplest generic model of animal life history.

NARCIS (Netherlands)

Jager, T.; Martin, B.T.; Zimmer, E.I.

2013-01-01

Understanding the life cycle of individual animals, and how it responds to stress, requires a model that causally links life-history traits (feeding, growth, development and reproduction). Dynamic Energy Budget (DEB) theory offers a powerful and formalised framework for building process-based models

The Mass-Longevity Triangle: Pareto Optimality and the Geometry of Life-History Trait Space.

Directory of Open Access Journals (Sweden)

Pablo Szekely

2015-10-01

Full Text Available When organisms need to perform multiple tasks they face a fundamental tradeoff: no phenotype can be optimal at all tasks. This situation was recently analyzed using Pareto optimality, showing that tradeoffs between tasks lead to phenotypes distributed on low dimensional polygons in trait space. The vertices of these polygons are archetypes--phenotypes optimal at a single task. This theory was applied to examples from animal morphology and gene expression. Here we ask whether Pareto optimality theory can apply to life history traits, which include longevity, fecundity and mass. To comprehensively explore the geometry of life history trait space, we analyze a dataset of life history traits of 2105 endothermic species. We find that, to a first approximation, life history traits fall on a triangle in log-mass log-longevity space. The vertices of the triangle suggest three archetypal strategies, exemplified by bats, shrews and whales, with specialists near the vertices and generalists in the middle of the triangle. To a second approximation, the data lies in a tetrahedron, whose extra vertex above the mass-longevity triangle suggests a fourth strategy related to carnivory. Each animal species can thus be placed in a coordinate system according to its distance from the archetypes, which may be useful for genome-scale comparative studies of mammalian aging and other biological aspects. We further demonstrate that Pareto optimality can explain a range of previous studies which found animal and plant phenotypes which lie in triangles in trait space. This study demonstrates the applicability of multi-objective optimization principles to understand life history traits and to infer archetypal strategies that suggest why some mammalian species live much longer than others of similar mass.

Spatially varying selection shapes life history clines among populations of Drosophila melanogaster from sub-Saharan Africa.

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Fabian, D K; Lack, J B; Mathur, V; Schlötterer, C; Schmidt, P S; Pool, J E; Flatt, T

2015-04-01

Clines in life history traits, presumably driven by spatially varying selection, are widespread. Major latitudinal clines have been observed, for example, in Drosophila melanogaster, an ancestrally tropical insect from Africa that has colonized temperate habitats on multiple continents. Yet, how geographic factors other than latitude, such as altitude or longitude, affect life history in this species remains poorly understood. Moreover, most previous work has been performed on derived European, American and Australian populations, but whether life history also varies predictably with geography in the ancestral Afro-tropical range has not been investigated systematically. Here, we have examined life history variation among populations of D. melanogaster from sub-Saharan Africa. Viability and reproductive diapause did not vary with geography, but body size increased with altitude, latitude and longitude. Early fecundity covaried positively with altitude and latitude, whereas lifespan showed the opposite trend. Examination of genetic variance-covariance matrices revealed geographic differentiation also in trade-off structure, and QST -FST analysis showed that life history differentiation among populations is likely shaped by selection. Together, our results suggest that geographic and/or climatic factors drive adaptive phenotypic differentiation among ancestral African populations and confirm the widely held notion that latitude and altitude represent parallel gradients. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Switch between life history strategies due to changes in glycolytic enzyme gene dosage in Saccharomyces cerevisiae.

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Wang, Shaoxiao; Spor, Aymé; Nidelet, Thibault; Montalent, Pierre; Dillmann, Christine; de Vienne, Dominique; Sicard, Delphine

2011-01-01

Adaptation is the process whereby a population or species becomes better fitted to its habitat through modifications of various life history traits which can be positively or negatively correlated. The molecular factors underlying these covariations remain to be elucidated. Using Saccharomyces cerevisiae as a model system, we have investigated the effects on life history traits of varying the dosage of genes involved in the transformation of resources into energy. Changing gene dosage for each of three glycolytic enzyme genes (hexokinase 2, phosphoglucose isomerase, and fructose-1,6-bisphosphate aldolase) resulted in variation in enzyme activities, glucose consumption rate, and life history traits (growth rate, carrying capacity, and cell size). However, the range of effects depended on which enzyme was expressed differently. Most interestingly, these changes revealed a genetic trade-off between carrying capacity and cell size, supporting the discovery of two extreme life history strategies already described in yeast populations: the "ants," which have lower glycolytic gene dosage, take up glucose slowly, and have a small cell size but reach a high carrying capacity, and the "grasshoppers," which have higher glycolytic gene dosage, consume glucose more rapidly, and allocate it to a larger cell size but reach a lower carrying capacity. These results demonstrate antagonist pleiotropy for glycolytic genes and show that altered dosage of a single gene drives a switch between two life history strategies in yeast.

Disparate relatives: Life histories vary more in genera occupying intermediate environments

Czech Academy of Sciences Publication Activity Database

Hermant, M.; Hennion, F.; Bartish, Igor V.; Yugel, B.; Prinzing, A.

2012-01-01

Roč. 14, č. 4 (2012), s. 283-301 ISSN 1433-8319 Institutional support: RVO:67985939 Keywords : life-history traits * dated phylogeny * regional trait variability Subject RIV: EF - Botanics Impact factor: 4.158, year: 2012

Deciphering the adjustment between environment and life history in annuals: lessons from a geographically-explicit approach in Arabidopsis thaliana.

Science.gov (United States)

Manzano-Piedras, Esperanza; Marcer, Arnald; Alonso-Blanco, Carlos; Picó, F Xavier

2014-01-01

The role that different life-history traits may have in the process of adaptation caused by divergent selection can be assessed by using extensive collections of geographically-explicit populations. This is because adaptive phenotypic variation shifts gradually across space as a result of the geographic patterns of variation in environmental selective pressures. Hence, large-scale experiments are needed to identify relevant adaptive life-history traits as well as their relationships with putative selective agents. We conducted a field experiment with 279 geo-referenced accessions of the annual plant Arabidopsis thaliana collected across a native region of its distribution range, the Iberian Peninsula. We quantified variation in life-history traits throughout the entire life cycle. We built a geographic information system to generate an environmental data set encompassing climate, vegetation and soil data. We analysed the spatial autocorrelation patterns of environmental variables and life-history traits, as well as the relationship between environmental and phenotypic data. Almost all environmental variables were significantly spatially autocorrelated. By contrast, only two life-history traits, seed weight and flowering time, exhibited significant spatial autocorrelation. Flowering time, and to a lower extent seed weight, were the life-history traits with the highest significant correlation coefficients with environmental factors, in particular with annual mean temperature. In general, individual fitness was higher for accessions with more vigorous seed germination, higher recruitment and later flowering times. Variation in flowering time mediated by temperature appears to be the main life-history trait by which A. thaliana adjusts its life history to the varying Iberian environmental conditions. The use of extensive geographically-explicit data sets obtained from field experiments represents a powerful approach to unravel adaptive patterns of variation. In a

Health Care Decisions at the End of Life: Theological and Ethical Foundations for Decision Making.

Science.gov (United States)

Allegretti, Joseph G.

This paper provides a framework for making sense of perplexing problems surrounding issues of death and dying by exploring the theological and ethical background to health care decision making at the end of life. The paper first examines several of the basic principles that theologians and secular ethicists employ when analyzing such questions.…

Age-based disparities in end-of-life decisions in Belgium: a population-based death certificate survey.

Science.gov (United States)

Chambaere, Kenneth; Rietjens, Judith A C; Smets, Tinne; Bilsen, Johan; Deschepper, Reginald; Pasman, H Roeline W; Deliens, Luc

2012-06-18

A growing body of scientific research is suggesting that end-of-life care and decision making may differ between age groups and that elderly patients may be the most vulnerable to exclusion of due care at the end of life. This study investigates age-related disparities in the rate of end-of-life decisions with a possible or certain life shortening effect (ELDs) and in the preceding decision making process in Flanders, Belgium in 2007, where euthanasia was legalised in 2002. Comparing with data from an identical survey in 1998 we also study the plausibility of the 'slippery slope' hypothesis which predicts a rise in the rate of administration of life ending drugs without patient request, especially among elderly patients, in countries where euthanasia is legal. We performed a post-mortem survey among physicians certifying a large representative sample (n = 6927) of death certificates in 2007, identical to a 1998 survey. Response rate was 58.4%. While the rates of non-treatment decisions (NTD) and administration of life ending drugs without explicit request (LAWER) did not differ between age groups, the use of intensified alleviation of pain and symptoms (APS) and euthanasia/assisted suicide (EAS), as well as the proportion of euthanasia requests granted, was bivariately and negatively associated with patient age. Multivariate analysis showed no significant effects of age on ELD rates. Older patients were less often included in decision making for APS and more often deemed lacking in capacity than were younger patients. Comparison with 1998 showed a decrease in the rate of LAWER in all age groups except in the 80+ age group where the rate was stagnant. Age is not a determining factor in the rate of end-of-life decisions, but is in decision making as patient inclusion rates decrease with old age. Our results suggest there is a need to focus advance care planning initiatives on elderly patients. The slippery slope hypothesis cannot be confirmed either in general or

Potential fitness benefits of the half-pounder life history in Klamath River steelhead

Science.gov (United States)

Hodge, Brian W.; Wilzbach, Peggy; Duffy, Walter G.

2014-01-01

Steelhead Oncorhynchus mykiss from several of the world's rivers display the half-pounder life history, a variant characterized by an amphidromous (and, less often, anadromous) return to freshwater in the year of initial ocean entry. We evaluated factors related to expression of the half-pounder life history in wild steelhead from the lower Klamath River basin, California. We also evaluated fitness consequences of the half-pounder phenotype using a simple life history model that was parameterized with our empirical data and outputs from a regional survival equation. The incidence of the half-pounder life history differed among subbasins of origin and smolt ages. Precocious maturation occurred in approximately 8% of half-pounders and was best predicted by individual length in freshwater preceding ocean entry. Adult steelhead of the half-pounder phenotype were smaller and less fecund at age than adult steelhead of the alternative (ocean contingent) phenotype. However, our data suggest that fish of the half-pounder phenotype are more likely to spawn repeatedly than are fish of the ocean contingent phenotype. Models predicted that if lifetime survivorship were equal between phenotypes, the fitness of the half-pounder phenotype would be 17–28% lower than that of the ocean contingent phenotype. To meet the condition of equal fitness between phenotypes would require that first-year ocean survival be 21–40% higher among half-pounders in freshwater than among their cohorts at sea. We concluded that continued expression of the half-pounder phenotype is favored by precocious maturation and increased survival relative to that of the ocean contingent phenotype.

Can sexual selection drive female life histories? A comparative study on Galliform birds.

Science.gov (United States)

Kolm, N; Stein, R W; Mooers, A Ø; Verspoor, J J; Cunningham, E J A

2007-03-01

Sexual selection has been identified as a major evolutionary force shaping male life history traits but its impact on female life history evolution is less clear. Here we examine the impact of sexual selection on three key female traits (body size, egg size and clutch size) in Galliform birds. Using comparative independent contrast analyses and directional discrete analyses, based on published data and a new genera-level supertree phylogeny of Galliform birds, we investigated how sexual selection [quantified as sexual size dimorphism (SSD) and social mating system (MS)] affects these three important female traits. We found that female body mass was strongly and positively correlated with egg size but not with clutch size, and that clutch size decreased as egg size increased. We established that SSD was related to MS, and then used SSD as a proxy of the strength of sexual selection. We found both a positive relationship between SSD and female body mass and egg size and that increases in female body mass and egg size tend to occur following increases in SSD in this bird order. This pattern of female body mass increases lagging behind changes in SSD, established using our directional discrete analysis, suggests that female body mass increases as a response to increases in the level of sexual selection and not simply through a strong genetic relationship with male body mass. This suggests that sexual selection is linked to changes in female life history traits in Galliformes and we discuss how this link may shape patterns of life history variation among species.

Emotional Impact of End-of-Life Decisions on Professional Relationships in the ICU: An Obstacle to Collegiality?

Science.gov (United States)

Laurent, Alexandra; Bonnet, Magalie; Capellier, Gilles; Aslanian, Pierre; Hebert, Paul

2017-12-01

End-of-life decisions are not only common in the ICU but also frequently elicit strong feelings among health professionals. Even though we seek to develop more collegial interprofessional approaches to care and health decision-making, there are many barriers to successfully managing complex decisions. The aim of this study is to better understand how emotions influence the end-of-life decision-making process among professionals working in ICU. Qualitative study with clinical interviews. All interviews were transcribed verbatim and analyzed thematically using interpretative phenomenological analysis. Two independent ICUs at the "Centre Hospitalier de l'Université de Montréal." Ten physicians and 10 nurses. None. During the end-of-life decision-making process, families and patients restructure the decision-making frame by introducing a strong emotional dimension. This results in the emergence of new challenges quite different from the immediacy often associated with intensive care. In response to changes in decision frames, physicians rely on their relationship with the patient's family to assist with advanced care decisions. Nurses, however, draw on their relationship and proximity to the patient to denounce therapeutic obstinacy. Our study suggests that during the end-of-life decision-making process, nurses' feelings toward their patients and physicians' feelings toward their patients' families influence the decisions they make. Although these emotional dimensions allow nurses and physicians to act in a manner that is consistent with their professional ethics, the professionals themselves seem to have a poor understanding of these dimensions and often overlook them, thus hindering collegial decisions.

Timing of seasonal migration in mule deer: effects of climate, plant phenology, andlife-history characteristics

OpenAIRE

Monteith, Kevin L.; Bleich, Vernon C.; Stephenson, Thomas R.; Pierce, Becky M.; Conner, Mary M.; Klaver, Robert W.; Bowyer, R. Terry

2011-01-01

Phenological events of plants and animals are sensitive to climatic processes. Migration is a life-history event exhibited by most large herbivores living in seasonal environments, and is thought to occur in response to dynamics of forage and weather. Decisions regarding when to migrate, however, may be affected by differences in life-history characteristics of individuals. Long-term and intensive study of a population of mule deer (Odocoileus hemionus) in the Sierra Nevada, California, USA, ...

Life histories of female elementary teachers and their science/teacher role construction

Science.gov (United States)

Ramseur, Aletha Johnson

The research conducted in this study focuses on life histories of female elementary teachers and their science/teacher role construction. Identity theorists argue that the self consists of a collection of identities founded on occupying a particular role. Who we are depends on the roles we occupy. These roles are often referred to as "role identities". In the case of these participants, many role identities (mother, wife, sibling, and teacher) exist. This study focuses primarily on their (science) teacher role identity. Literature on women's lives, as learners and teachers, suggest that women's experiences, currently and throughout history influenced their teacher role construction. There is however, little knowledge of women's lives as elementary teachers of science and the affect of their experiences, currently and throughout history, on their (science) teacher identity construction. Schools delineated by race, class, and gender relations, are similar to other sectors of society's, social and cultural spheres within which race, class, and gender identities are constructed. Using in-depth-interviews female elementary teachers were encouraged to actively reconstruct their life and work-life experiences focusing on family, school and science interactions. They addressed the intellectual and emotional connections between their life and work experiences by focusing on details of their past and present experiences and examining the meaning of those experiences. It was the scrutiny of these connections between their life and work experiences, the meaning derived from them and historical events, and the constraints imposed on their personal choices by broader power relations, such as those of class, race, and gender that informed why we teach, how we teach, and what we teach.

Life history types and strategies

DEFF Research Database (Denmark)

Boel, Mikkel

strategies and types in migratory freshwater fish, using brown trout and alewife as study organisms. Firstly, we investigated underlying mechanisms of resident and migratory life history strategies of salmonids, using indicators for nutritional status, stress, tissue damage and smoltification. Secondly...... III the minimum predation from cormorants and herons was estimated over a three year period on the brown trout population of of Lake Hald. The magnitude of the predation pressure from both bird species were very similar and when summed up, the avian predation accounted for an average minimum of 37.......2 % of the annual brown trout mortality in the lake and 10.1 % in the tributaries. This result illustrates that avian predation in the lake can be quite substantial and potentially plays an important role in the population dynamics of brown trout. Cormorants alone were responsible 21.2% in the lake and the arrival...

Entanglement is a costly life-history stage in large whales.

Science.gov (United States)

van der Hoop, Julie; Corkeron, Peter; Moore, Michael

2017-01-01

Individuals store energy to balance deficits in natural cycles; however, unnatural events can also lead to unbalanced energy budgets. Entanglement in fishing gear is one example of an unnatural but relatively common circumstance that imposes energetic demands of a similar order of magnitude and duration of life-history events such as migration and pregnancy in large whales. We present two complementary bioenergetic approaches to estimate the energy associated with entanglement in North Atlantic right whales, and compare these estimates to the natural energetic life history of individual whales. Differences in measured blubber thicknesses and estimated blubber volumes between normal and entangled, emaciated whales indicate between 7.4 × 10 10  J and 1.2 × 10 11  J of energy are consumed during the course to death of a lethal entanglement. Increased thrust power requirements to overcome drag forces suggest that when entangled, whales require 3.95 × 10 9 to 4.08 × 10 10  J more energy to swim. Individuals who died from their entanglements performed significantly more work (energy expenditure × time) than those that survived; entanglement duration is therefore critical in determining whales' survival. Significant sublethal energetic impacts also occur, especially in reproductive females. Drag from fishing gear contributes up to 8% of the 4-year female reproductive energy budget, delaying time of energetic equilibrium (to restore energy lost by a particular entanglement) for reproduction by months to years. In certain populations, chronic entanglement in fishing gear can be viewed as a costly unnatural life-history stage, rather than a rare or short-term incident.

Evaluating a Clinical Decision Support Interface for End-of-Life Nurse Care.

Science.gov (United States)

Febretti, Alessandro; Stifter, Janet; Keenan, Gail M; Lopez, Karen D; Johnson, Andrew; Wilkie, Diana J

2014-01-01

Clinical Decision Support Systems (CDSS) are tools that assist healthcare personnel in the decision-making process for patient care. Although CDSSs have been successfully deployed in the clinical setting to assist physicians, few CDSS have been targeted at professional nurses, the largest group of health providers. We present our experience in designing and testing a CDSS interface embedded within a nurse care planning and documentation tool. We developed four prototypes based on different CDSS feature designs, and tested them in simulated end-of-life patient handoff sessions with a group of 40 nurse clinicians. We show how our prototypes directed nurses towards an optimal care decision that was rarely performed in unassisted practice. We also discuss the effect of CDSS layout and interface navigation in a nurse's acceptance of suggested actions. These findings provide insights into effective nursing CDSS design that are generalizable to care scenarios different than end-of-life.

Life history of the stem tetrapod Acanthostega revealed by synchrotron microtomography.

Science.gov (United States)

Sanchez, Sophie; Tafforeau, Paul; Clack, Jennifer A; Ahlberg, Per E

2016-09-15

The transition from fish to tetrapod was arguably the most radical series of adaptive shifts in vertebrate evolutionary history. Data are accumulating rapidly for most aspects of these events, but the life histories of the earliest tetrapods remain completely unknown, leaving a major gap in our understanding of these organisms as living animals. Symptomatic of this problem is the unspoken assumption that the largest known Devonian tetrapod fossils represent adult individuals. Here we present the first, to our knowledge, life history data for a Devonian tetrapod, from the Acanthostega mass-death deposit of Stensiö Bjerg, East Greenland. Using propagation phase-contrast synchrotron microtomography (PPC-SRμCT) to visualize the histology of humeri (upper arm bones) and infer their growth histories, we show that even the largest individuals from this deposit are juveniles. A long early juvenile stage with unossified limb bones, during which individuals grew to almost final size, was followed by a slow-growing late juvenile stage with ossified limbs that lasted for at least six years in some individuals. The late onset of limb ossification suggests that the juveniles were exclusively aquatic, and the predominance of juveniles in the sample suggests segregated distributions of juveniles and adults at least at certain times. The absolute size at which limb ossification began differs greatly between individuals, suggesting the possibility of sexual dimorphism, adaptive strategies or competition-related size variation.

Life history parameters of narwhals (Monodon monoceros) from Greenland

DEFF Research Database (Denmark)

Garde, Eva; Hansen, Steen H; Ditlevsen, Susanne

2015-01-01

Life history parameters for narwhals (Monodon monoceros) were estimated based on age estimates from aspartic acid racemization of eye lens nuclei. Eyes, reproductive organs, and measures of body lengths were collected from 282 narwhals in East and West Greenland in the years 1993, 2004, and 2007–...... projection matrix was parameterized with the data on age structure and fertility rates. The annual rate of increase of narwhals in East Greenland was estimated to be 3.8% while narwhals in West Greenland had a rate of increase at 2.6%. Key words:......Life history parameters for narwhals (Monodon monoceros) were estimated based on age estimates from aspartic acid racemization of eye lens nuclei. Eyes, reproductive organs, and measures of body lengths were collected from 282 narwhals in East and West Greenland in the years 1993, 2004, and 2007......–2010. Age estimates were based on the racemization of L-aspartic acid to D-aspartic acid in the nucleus of the eye lens. The ratio of D- and L-enantiomers was measured using high-performance liquid chromatography. The age equation used, 420.32X − 24.02·year where X is the D/L ratio, was determined from data...

Modafinil alters decision making based on feedback history - a randomized placebo-controlled double blind study in humans.

Science.gov (United States)

Bellebaum, Christian; Kuchinke, Lars; Roser, Patrik

2017-02-01

Modafinil is becoming increasingly popular as a cognitive enhancer. Research on the effects of modafinil on cognitive function have yielded mixed results, with negative findings for simple memory and attention tasks and enhancing effects for more complex tasks. In the present study we examined whether modafinil, due to its known effect on the dopamine level in the striatum, alters feedback-related choice behaviour. We applied a task that separately tests the choice of previously rewarded behaviours (approach) and avoidance of previously punished behaviours. 18 participants received a single dose of 200 mg modafinil. Their performance was compared to a group of 22 participants who received placebo in a double-blind design. Modafinil but not placebo induced a significant bias towards approach behaviour as compared to the frequency of avoidance behaviour. General attention, overall feedback-based acquisition of choice behaviour and reaction times in high vs low conflict choices were not significantly affected by modafinil. This finding suggests that modafinil has a specific effect on dopamine-mediated choice behaviour based on the history of feedback, while a contribution of noradrenaline is also conceivable. The described change in decision making cannot be considered as cognitive enhancement, but might rather have detrimental effects on decisions in everyday life.

Modernization and gender regimes, life histories of the wives of Turkish political leaders

NARCIS (Netherlands)

Yelsali Parmaksiz, Pinar Melis

2009-01-01

This work is a close look at the life histories of the top Turkish political leaders with the aim of analyzing changes in gender role and gender identity and tensions between the two in the history of Turkish modernization vis-à-vis with contemporaneous debates on gender. The main objective is to

Predicting the natural mortality of marine fish from life history characteristics

DEFF Research Database (Denmark)

Gislason, Henrik

For fish much of the life history is determined by body size. Body size and asymptotic size significantly influences important life history processes such as growth, maturity, egg production, and natural mortality. Futhermore, for a population to persist, offspring must be able to replace...... their parents on a one-for-one basis in the long run. Otherwise the population would either increase exponentially or become extinct. Combining data on growth and specific fecundity in a size-based fish community model of the North Sea and using the requirement of a one-for-one replacement provides...... the information necessary to estimate the scaling of natural mortality with size and asymptotic size. The estimated scaling is compared with output from multispecies fish stock models, with the empirical scaling of the maximum number of recruits per unit of spawning stock biomass with body size...

Life history traits of Bathyclarias nyasensis (Siluroidei) in Lake Malawi

African Journals Online (AJOL)

Life history traits, including age, growth, reproduction and diet of Bathyclarias nyasensis from Lake Malawi were studied between December 1996 and November 1998. Owing to reabsorp tion of pectoral spines with increasing fish size, and the relatively low number of spines that could be aged reliably, only otoliths were ...

Medical end-of-life decisions in Switzerland 2001 and 2013: Who is involved and how does the decision-making capacity of the patient impact?

Science.gov (United States)

Schmid, Margareta; Zellweger, Ueli; Bosshard, Georg; Bopp, Matthias

2016-01-01

In Switzerland, the prevalence of medical end-of-life practices had been assessed on a population level only once - in 2001 - until in 2013/14 an identical study was conducted. We aimed to compare the results of the 2001 and 2013 studies with a special focus on shared decision-making and patients' decision-making capacity. Our study encompassed a 21.3% sample of deaths among residents of the German-speaking part of Switzerland aged 1 year or older. From 4998 mailed questionnaires, 3173 (63.5%) were returned. All data were weighted to adjust for age- and sex-specific differences in response rates. Cases with at least one reported end-of-life practice significantly increased from 74.5% (2001) to 82.3% (2013) of all deaths eligible for an end-of-life decision (p Switzerland, there remains potential for further improvement in shared decision-making. Efforts to motivate physicians to involve patients and relatives may be a win-win situation.

Haemodialysis patients and end-of-life decisions: a theory of personal preservation.

Science.gov (United States)

Calvin, Amy Olivier

2004-06-01

Lack of knowledge about the end-of-life treatment preferences of patients undergoing haemodialysis is problematic in the acute care setting as, often, patients are unable to communicate their treatment wishes effectively and have not previously documented their desires in the form of advance directives. Existing theoretical models offer an incomplete explanation of end-of-life treatment decisions in haemodialysis patients. This paper reports a study exploring decisions about end-of-life treatment (e.g. cardiopulmonary resuscitation, mechanical ventilation) in people with kidney failure undergoing haemodialysis. Grounded theory was used. Theoretical sampling led to selection of 20 haemodialysis patients (11 men and nine women with a mean age of 56) who attended three dialysis outpatient centres in central Texas. They were interviewed about end-of-life treatment plans and the use of advance directives (i.e. living wills and durable powers of attorney for health care). Interviews, transcripts and field notes from the first 12 patients were analysed by making constant comparisons. The remaining eight interviews were used for validation purposes. Data collection and analysis spanned the years 1997-2000. When prompted to think about and discuss end-of-life treatments, haemodialysis patients chose to focus on living rather than dying. A substantive theory of 'personal preservation' was developed. This consists of three phases: knowing the odds for survival, defining individuality (beating the odds, discovering meaning, being optimistic and having faith in a higher force) and personal preservation (being responsible and taking chances). The theory of personal preservation furthers understanding of illness behaviour and the process by which patients make decisions about end-of-life treatments. It can be used to sensitize health care professionals to patients' desires and to enhance patient-professional communication.

Psychometrics and life history strategy: the structure and validity of the High K Strategy Scale.

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Copping, Lee T; Campbell, Anne; Muncer, Steven

2014-03-22

In this paper, we critically review the conceptualization and implementation of psychological measures of life history strategy associated with Differential K theory. The High K Strategy Scale (HKSS: Giosan, 2006) was distributed to a large British sample (n = 809) with the aim of assessing its factor structure and construct validity in relation to theoretically relevant life history variables: age of puberty, age of first sexual encounter, and number of sexual partners. Exploratory and confirmatory factor analyses indicated that the HKSS in its current form did not show an adequate statistical fit to the data. Modifications to improve fit indicated four correlated factors (personal capital, environmental stability, environmental security, and social capital). Later puberty in women was positively associated with measures of the environment and personal capital. Among men, contrary to Differential K predictions but in line with female mate preferences, earlier sexual debut and more sexual partners were positively associated with more favorable environments and higher personal and social capital. We raise concerns about the use of psychometric indicators of lifestyle and personality as proxies for life history strategy when they have not been validated against objective measures derived from contemporary life history theory and when their status as causes, mediators, or correlates has not been investigated.

Response of endemic Clarias species' life-history biometrics to land ...

African Journals Online (AJOL)

The Mpologoma River wetland is highly negatively impacted by rice growing and yet it provides habitat to endemic Clarias species that are important to the wetland fishery. Variations in life-history biometrics of small Clarias species at various wetland sites in relation to land-use changes within the wetland were studied in ...

Application of preference selection index method for decision making over the design stage of production system life cycle

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Rajesh Attri

2015-07-01

Full Text Available The life cycle of production system shows the progress of production system from the inception to the termination of the system. During each stage, mainly in the design stage, certain strategic decisions have to be taken. These decisions are more complex as the decision makers have to assess a wide range of alternatives based on a set of conflicting criteria. As the decision making process is found to be unstructured, characterized by domain dependent knowledge, there is a need to apply an efficient multi-criteria decision making (MCDM tool to help the decision makers in making correct decisions. This paper explores the application of a novel MCDM method i.e. Preference selection index (PSI method to solve various decision-making problems that are generally encountered in the design stage of production system life cycle. To prove the potentiality, applicability and accuracy of PSI method in solving decision making problem during the design stage of production system life cycle, five examples are cited from the literature and are compared with the results obtained by the past researchers.

The Treatment of Geological Time & the History of Life on Earth in High School Biology Textbooks

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Summers, Gerald; Decker, Todd; Barrow, Lloyd

2007-01-01

In spite of the importance of geological time in evolutionary biology, misconceptions about historical events in the history of life on Earth are common. Glenn (1990) has documented a decline from 1960 to 1989 in the amount of space devoted to the history of life in high school earth science textbooks, but we are aware of no similar study in…

A new view of avian life-history evolution tested on an incubation paradox.

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Martin, Thomas E

2002-02-07

Viewing life-history evolution in birds based on an age-specific mortality framework can explain broad life-history patterns, including the long incubation periods in southern latitudes documented here. I show that incubation periods of species that are matched phylogenetically and ecologically between Argentina and Arizona are longer in Argentina. Long incubation periods have mystified scientists because they increase the accumulated risk of time-dependent mortality to young without providing a clear benefit. I hypothesize that parents of species with low adult mortality accept increased risk of mortality to their young from longer incubation if this allows reduced risk of mortality to themselves. During incubation, songbird parents can reduce risk of mortality to themselves by reducing nest attentiveness (percentage of time on the nest). Here I show that parents of species with lower adult mortality exhibit reduced nest attentiveness and that lower attentiveness is associated with longer incubation periods. However, the incubation period is also modified by juvenile mortality. Clutch size variation is also strongly correlated with age-specific mortality. Ultimately, adult and juvenile mortality explain variation in incubation and other life-history traits better than the historical paradigm.

Intrapopulation genome size variation in D. melanogaster reflects life history variation and plasticity.

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Lisa L Ellis

2014-07-01

Full Text Available We determined female genome sizes using flow cytometry for 211 Drosophila melanogaster sequenced inbred strains from the Drosophila Genetic Reference Panel, and found significant conspecific and intrapopulation variation in genome size. We also compared several life history traits for 25 lines with large and 25 lines with small genomes in three thermal environments, and found that genome size as well as genome size by temperature interactions significantly correlated with survival to pupation and adulthood, time to pupation, female pupal mass, and female eclosion rates. Genome size accounted for up to 23% of the variation in developmental phenotypes, but the contribution of genome size to variation in life history traits was plastic and varied according to the thermal environment. Expression data implicate differences in metabolism that correspond to genome size variation. These results indicate that significant genome size variation exists within D. melanogaster and this variation may impact the evolutionary ecology of the species. Genome size variation accounts for a significant portion of life history variation in an environmentally dependent manner, suggesting that potential fitness effects associated with genome size variation also depend on environmental conditions.

Can family risk-factors moderate the link between psychopathy and life-history strategy?

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Međedović Janko

2016-01-01

Full Text Available Life History Theory is an explanatory evolutionary framework which explains differences in fitness-relevant outcomes using the characteristics of the environment and individual organisms. Basically, individuals can be positioned somewhere on the r/K continuum of the Life History Strategy (LHS: a K or slow strategy represents later maturity and reproduction, a smaller number of offspring with higher investment in them, while the r (or fast strategy follows the opposite pattern. Previous research offered evidence that psychopathy can represent a trait associated with fast LHS. In the present research we examined the relations between the family risk-factors, a four-factor model of psychopathy and the LHS in a sample of male convicts (N=181. The results have shown that a manipulative and deceitful interpersonal style is associated with slow LHS while shallow affect and antisocial tendencies are related to fast LHS. The interactions between psychopathy and family risk-factors revealed that parental criminal behaviour enhances the relation between fast LHS and psychopathic traits, including the manipulative interpersonal style. The findings are in accordance with the Life History Theory and provide a deeper understanding of the preservation of psychopathy in contemporary populations.

Intrapopulation Genome Size Variation in D. melanogaster Reflects Life History Variation and Plasticity

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Ellis, Lisa L.; Huang, Wen; Quinn, Andrew M.; Ahuja, Astha; Alfrejd, Ben; Gomez, Francisco E.; Hjelmen, Carl E.; Moore, Kristi L.; Mackay, Trudy F. C.; Johnston, J. Spencer; Tarone, Aaron M.

2014-01-01

We determined female genome sizes using flow cytometry for 211 Drosophila melanogaster sequenced inbred strains from the Drosophila Genetic Reference Panel, and found significant conspecific and intrapopulation variation in genome size. We also compared several life history traits for 25 lines with large and 25 lines with small genomes in three thermal environments, and found that genome size as well as genome size by temperature interactions significantly correlated with survival to pupation and adulthood, time to pupation, female pupal mass, and female eclosion rates. Genome size accounted for up to 23% of the variation in developmental phenotypes, but the contribution of genome size to variation in life history traits was plastic and varied according to the thermal environment. Expression data implicate differences in metabolism that correspond to genome size variation. These results indicate that significant genome size variation exists within D. melanogaster and this variation may impact the evolutionary ecology of the species. Genome size variation accounts for a significant portion of life history variation in an environmentally dependent manner, suggesting that potential fitness effects associated with genome size variation also depend on environmental conditions. PMID:25057905

Niche partitioning in sympatric Gorilla and Pan from Cameroon: implications for life history strategies and for reconstructing the evolution of hominin life history.

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Macho, Gabriele A; Lee-Thorp, Julia A

2014-01-01

Factors influencing the hominoid life histories are poorly understood, and little is known about how ecological conditions modulate the pace of their development. Yet our limited understanding of these interactions underpins life history interpretations in extinct hominins. Here we determined the synchronisation of dental mineralization/eruption with brain size in a 20th century museum collection of sympatric Gorilla gorilla and Pan troglodytes from Central Cameroon. Using δ13C and δ15N of individuals' hair, we assessed whether and how differences in diet and habitat use may have impacted on ape development. The results show that, overall, gorilla hair δ13C and δ15N values are more variable than those of chimpanzees, and that gorillas are consistently lower in δ13C and δ15N compared to chimpanzees. Within a restricted, isotopically-constrained area, gorilla brain development appears delayed relative to dental mineralization/eruption [or dental development is accelerated relative to brains]: only about 87.8% of adult brain size is attained by the time first permanent molars come into occlusion, whereas it is 92.3% in chimpanzees. Even when M1s are already in full functional occlusion, gorilla brains lag behind those of chimpanzee (91% versus 96.4%), relative to tooth development. Both bootstrap analyses and stable isotope results confirm that these results are unlikely due to sampling error. Rather, δ15N values imply that gorillas are not fully weaned (physiologically mature) until well after M1 are in full functional occlusion. In chimpanzees the transition from infant to adult feeding appears (a) more gradual and (b) earlier relative to somatic development. Taken together, the findings are consistent with life history theory that predicts delayed development when non-density dependent mortality is low, i.e. in closed habitats, and with the "risk aversion" hypothesis for frugivorous species as a means to avert starvation. Furthermore, the results highlight

Niche partitioning in sympatric Gorilla and Pan from Cameroon: implications for life history strategies and for reconstructing the evolution of hominin life history.

Directory of Open Access Journals (Sweden)

Gabriele A Macho

Full Text Available Factors influencing the hominoid life histories are poorly understood, and little is known about how ecological conditions modulate the pace of their development. Yet our limited understanding of these interactions underpins life history interpretations in extinct hominins. Here we determined the synchronisation of dental mineralization/eruption with brain size in a 20th century museum collection of sympatric Gorilla gorilla and Pan troglodytes from Central Cameroon. Using δ13C and δ15N of individuals' hair, we assessed whether and how differences in diet and habitat use may have impacted on ape development. The results show that, overall, gorilla hair δ13C and δ15N values are more variable than those of chimpanzees, and that gorillas are consistently lower in δ13C and δ15N compared to chimpanzees. Within a restricted, isotopically-constrained area, gorilla brain development appears delayed relative to dental mineralization/eruption [or dental development is accelerated relative to brains]: only about 87.8% of adult brain size is attained by the time first permanent molars come into occlusion, whereas it is 92.3% in chimpanzees. Even when M1s are already in full functional occlusion, gorilla brains lag behind those of chimpanzee (91% versus 96.4%, relative to tooth development. Both bootstrap analyses and stable isotope results confirm that these results are unlikely due to sampling error. Rather, δ15N values imply that gorillas are not fully weaned (physiologically mature until well after M1 are in full functional occlusion. In chimpanzees the transition from infant to adult feeding appears (a more gradual and (b earlier relative to somatic development. Taken together, the findings are consistent with life history theory that predicts delayed development when non-density dependent mortality is low, i.e. in closed habitats, and with the "risk aversion" hypothesis for frugivorous species as a means to avert starvation. Furthermore, the

A Course on Humanistic Creativity in Later Life: Literature Review, Case Histories, and Recommendations.

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Nuessel, Frank; Van Stewart, Arthur; Cedeno, Aristofanes

2001-01-01

Presents case histories of late-life creativity in literature (May Sarton), painting (Marcel Duchamp), music (Leos Janacek), dance (Martha Graham), and theatre (Jessica Tandy). Offers suggestions for a course on humanistic creativity in later life. (Contains 74 references.) (SK)

The Surprising History of Claims for Life on the Sun

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Crowe, Michael J.

2011-11-01

Because astronomers are now convinced that it is impossible for life, especially intelligent life, to exist on the Sun and stars, it might be assumed that astronomers have always held this view. This paper shows that throughout most of the history of astronomy, some intellectuals, including a number of well-known astronomers, have advocated the existence of intelligent life on our Sun and thereby on stars. Among the more prominent figures discussed are Nicolas of Cusa, Giordano Bruno, William Whiston, Johann Bode, Roger Boscovich, William Herschel, Auguste Comte, Carl Gauss, Thomas Dick, John Herschel, and François Arago. One point in preparing this paper is to show differences between the astronomy of the past and that of the present.

Age-based disparities in end-of-life decisions in Belgium: a population-based death certificate survey

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Chambaere Kenneth

2012-06-01

Full Text Available Abstract Background A growing body of scientific research is suggesting that end-of-life care and decision making may differ between age groups and that elderly patients may be the most vulnerable to exclusion of due care at the end of life. This study investigates age-related disparities in the rate of end-of-life decisions with a possible or certain life shortening effect (ELDs and in the preceding decision making process in Flanders, Belgium in 2007, where euthanasia was legalised in 2002. Comparing with data from an identical survey in 1998 we also study the plausibility of the ‘slippery slope’ hypothesis which predicts a rise in the rate of administration of life ending drugs without patient request, especially among elderly patients, in countries where euthanasia is legal. Method We performed a post-mortem survey among physicians certifying a large representative sample (n = 6927 of death certificates in 2007, identical to a 1998 survey. Response rate was 58.4%. Results While the rates of non-treatment decisions (NTD and administration of life ending drugs without explicit request (LAWER did not differ between age groups, the use of intensified alleviation of pain and symptoms (APS and euthanasia/assisted suicide (EAS, as well as the proportion of euthanasia requests granted, was bivariately and negatively associated with patient age. Multivariate analysis showed no significant effects of age on ELD rates. Older patients were less often included in decision making for APS and more often deemed lacking in capacity than were younger patients. Comparison with 1998 showed a decrease in the rate of LAWER in all age groups except in the 80+ age group where the rate was stagnant. Conclusion Age is not a determining factor in the rate of end-of-life decisions, but is in decision making as patient inclusion rates decrease with old age. Our results suggest there is a need to focus advance care planning initiatives on elderly patients. The

Trends in End-of-Life Decision Making in Patients With and Without Cancer

NARCIS (Netherlands)

Pardon, K.; Chambaere, K.; Pasman, H.R.W.; Deschepper, R.; Rietjens, J.; Deliens, L.

2013-01-01

Purpose: Because of cancer's high symptom burden and specific disease course, patients with cancer are more likely than other patients to face end-of-life decisions that have possible or certain life-shortening effects (ELDs). This study examines the incidence of ELDs in patients with cancer

Patients' preferences for participation in treatment decision-making at the end of life: qualitative interviews with advanced cancer patients.

Science.gov (United States)

Brom, Linda; Pasman, H Roeline W; Widdershoven, Guy A M; van der Vorst, Maurice J D L; Reijneveld, Jaap C; Postma, Tjeerd J; Onwuteaka-Philipsen, Bregje D

2014-01-01

Patients are often encouraged to participate in treatment decision-making. Most studies on this subject focus on choosing between different curative treatment types. In the last phase of life treatment decisions differ as they often put more emphasis on weighing quantity against quality of life, such as whether or not to start treatment aimed at life prolongation but with the possibility of side effects. This study aimed to obtain insight into cancer patients' preferences and the reasons for patients' preferred role in treatment decision-making at the end of life. 28 advanced cancer patients were included at the start of their first line treatment. In-depth interviews were held prior to upcoming treatment decisions whether or not to start a life prolonging treatment. The Control Preference Scale was used to start discussing the extent and type of influence patients wanted to have concerning upcoming treatment decision-making. Interviews were audio taped and transcribed. All patients wanted their physician to participate in the treatment decision-making process. The extent to which patients themselves preferred to participate seemed to depend on how patients saw their own role or assessed their own capabilities for participating in treatment decision-making. Patients foresaw a shift in the preferred level of participation to a more active role depending in the later phase of illness when life prolongation would become more limited and quality of life would become more important. Patients vary in how much involvement they would like to have in upcoming treatment decision-making. Individual patients' preferences may change in the course of the illness, with a shift to more active participation in the later phases. Communication about patients' expectations, wishes and preferences for participation in upcoming treatment decisions is of great importance. An approach in which these topics are openly discussed would be beneficial.

[End of life decisions, the Dutch form through Spanish eyes].

Science.gov (United States)

Belloc Rocasalbas, M; Girbes, A R J

2011-03-01

Abroad, but also in The Netherlands, there are many misunderstandings concerning end of life decisions and euthanasia. In general, euthanasia does not play any role in the intensive care units, simply because it does not fulfill the conditions to carry it out. However, there is still confusion, merely due to the assumption that the Dutch situation is different because of their legislation on euthanasia. The use of the unclear terminology such as "passive euthanasia", "voluntary euthanasia" or "involuntary euthanasia" contributes to the confusion of lay people and physicians, and should therefore be avoided. End of life decisions in intensive care patients are in fact a structural part of work of intensivists. Collecting all necessary information including the wishes and will of the patient, medical expertise and acknowledging limitations of medical treatment will help to determine futility of treatment goals. Once it is determined that surviving the intensive care unit with a quality of life acceptable for the patient is beyond reach, the goal of treatment should be improved and the dying process optimized. Stopping a treatment modality at the request of a will-competent patient or because of futility is not euthanasia. Copyright © 2010 Elsevier España, S.L. y SEMICYUC. All rights reserved.

Rapid evolution of parasite life history traits on an expanding range-edge.

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Kelehear, Crystal; Brown, Gregory P; Shine, Richard

2012-04-01

Parasites of invading species undergoing range advance may be exposed to powerful new selective forces. Low host density in range-edge populations hampers parasite transmission, requiring the parasite to survive longer periods in the external environment before encountering a potential host. These conditions should favour evolutionary shifts in offspring size to maximise parasite transmission. We conducted a common-garden experiment to compare life history traits among seven populations of the nematode lungworm (Rhabdias pseudosphaerocephala) spanning from the parasite population core to the expanding range-edge in invasive cane toads (Rhinella marina) in tropical Australia. Compared to conspecifics from the population core, nematodes from the range-edge exhibited larger eggs, larger free-living adults and larger infective larvae, and reduced age at maturity in parasitic adults. These results support a priori predictions regarding adaptive changes in offspring size as a function of invasion history, and suggest that parasite life history traits can evolve rapidly in response to the selective forces exerted by a biological invasion. © 2012 Blackwell Publishing Ltd/CNRS.

End-of-life medical decisions in France: a death certificate follow-up survey 5 years after the 2005 act of parliament on patients' rights and end of life.

Science.gov (United States)

Pennec, Sophie; Monnier, Alain; Pontone, Silvia; Aubry, Régis

2012-12-03

The "Patients' Rights and End of Life Care" Act came into force in France in 2005. It allows withholding/withdrawal of life-support treatment, and intensified use of medications that may hasten death through a double effect, as long as hastening death is not the purpose of the decision. It also specifies the requirements of the decision-making process. This study assesses the situation by examining the frequency of end-of-life decisions by patients' and physicians' characteristics, and describes the decision-making processes. We conducted a nationwide retrospective study of a random sample of adult patients who died in December 2009. Questionnaires were mailed to the physicians who certified/attended these deaths. Cases were weighted to adjust for response rate bias. Bivariate analyses and logistic regressions were performed for each decision. Of all deaths, 16.9% were sudden deaths with no information about end of life, 12.2% followed a decision to do everything possible to prolong life, and 47.7% followed at least one medical decision that may certainly or probably hasten death: withholding (14.6%) or withdrawal (4.2%) of treatments, intensified use of opioids and/or benzodiazepines (28.1%), use of medications to deliberately hasten death (i.e. not legally authorized) (0.8%), at the patient's request (0.2%) or not (0.6%). All other variables held constant, cause of death, patient's age, doctor's age and specialty, and place of death, influenced the frequencies of decisions. When a decision was made, 20% of the persons concerned were considered to be competent. The decision was discussed with the patient if competent in 40% (everything done) to 86% (intensification of alleviation of symptoms) of cases. Legal requirements regarding decision-making for incompetent patients were frequently not complied with. This study shows that end-of-life medical decisions are common in France. Most are in compliance with the 2005 law (similar to some other European countries

The Forms and Functions of Real-Life Moral Decision-Making.

Science.gov (United States)

Krebs, Dennis L.; Denton, Kathy; Wark, Gillian

1997-01-01

Observes that the Kohlbergian model of morality does not give a good account of the ways in which people make moral decisions in their everyday lives. Argues that a functional model of moral judgment and moral behavior derived from evolutionary theory may supply a better account of real-life morality. (DSK)

Effect of criminal defendant's history of childhood sexual abuse and personality disorder diagnosis on juror decision making.

Science.gov (United States)

Butler, Ebony; Jacquin, Kristine

2014-08-01

This study investigated whether a defendant's history of childhood sexual abuse (CSA) and/or personality disorder (PD) diagnosis affected juror decision making in a child sexual abuse trial. The PDs in the study were borderline PD and antisocial PD. Participants were 385 college students, 121 men and 264 women, who read a summary of a mock criminal trial and then made various juror decisions. Trial summaries were prepared by the principal investigator and were all uniform in content, length and detail. For the trial, both the defendant's gender and victim's gender were specified. The defendant was male, and the alleged victim was female. When the verdict was assessed, the results yielded that when the defendant's CSA history was presented, juror guilt ratings were higher than when there was no history of CSA. Similarly, when the defendant had a PD diagnosis, there were higher guilt ratings than when there was no PD diagnosis. CSA history and PD diagnosis were significant predictors of guilt ratings, suggesting that jurors perceive defendants more negatively if they have either been sexually abused as a child or have borderline or antisocial PD. Copyright © 2014 John Wiley & Sons, Ltd.

Migration of steelhead - Genetic basis of migratory tendency and life history plasticity in Oncorhynchus mykiss

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Steelhead and rainbow trout are the same species. However, their life histories diverge - with steelhead undertaking an anadromous life cycle whereas rainbow trout...

The end of life decisions -- should physicians aid their patients in dying?

Science.gov (United States)

Sharma, B R

2004-06-01

Decisions pertaining to end of life whether legalized or otherwise, are made in many parts of the world but not reported on account of legal implications. The highly charged debate over voluntary euthanasia and physician assisted suicide was brought into the public arena again when two British doctors confessed to giving lethal doses of drugs to hasten the death of terminally ill patients. Lack of awareness regarding the distinction between different procedures on account of legal status granted to them in some countries is the other area of concern. Some equate withdrawal of life support measures to physician assisted suicide whereas physician assisted suicide is often misinterpreted as euthanasia. Debate among the medical practitioners, law makers and the public taking into consideration the cultural, social and religious ethos will lead to increased awareness, more safeguards and improvement of medical decisions concerning the end of life. International Human Rights Law can provide a consensual basis for such a debate on euthanasia.

Life-history strategies as a tool to identify conservation constraints: A case-study on ants in chalk grasslands

NARCIS (Netherlands)

Noordwijk, C.G.E.; Boer, P.; Mabelis, A.A.; Verberk, W.C.E.P.; Siepel, H.

2012-01-01

Species’ life-history traits underlie species–environment relationships. Therefore, analysis of species traits, combined into life-history strategies, can be used to identify key factors shaping the local species composition. This is demonstrated in a case-study on ants in chalk grasslands. We

Life-history strategies in parasitoid wasps: a comparative analysis of 'ovigeny'

NARCIS (Netherlands)

Jervis, M.A.; Heimpel, G.E.; Ferns, P.N.; Harvey, J.A.; Kidd, N.A.C.

2001-01-01

1. Ecologists concerned with life-history strategies of parasitoid wasps have recently focused on interspecific variation in the fraction of the maximum potential lifetime egg complement that is mature when the female emerges into the environment. Species that have all of this complement mature upon

Disparate relatives: Life histories vary more in genera occupying intermediate environments

NARCIS (Netherlands)

Hermant, M.; Hennion, F.; Bartish, I.V.; Yguel, B.; Prinzing, A.

2012-01-01

Species within clades are commonly assumed to share similar life history traits, but within a given region some clades show much greater variability in traits than others. Are variable clades older, allowing more time for trait diversification? Or do they occupy particular environments, providing a

Labelling of end-of-life decisions by physicians.

Science.gov (United States)

Deyaert, Jef; Chambaere, Kenneth; Cohen, Joachim; Roelands, Marc; Deliens, Luc

2014-07-01

Potentially life-shortening medical end-of-life practices (end-of-life decisions (ELDs)) remain subject to conceptual vagueness. This study evaluates how physicians label these practices by examining which of their own practices (described according to the precise act, the intention, the presence of an explicit patient request and the self-estimated degree of life shortening)they label as euthanasia or sedation. We conducted a large stratified random sample of death certificates from 2007 (N=6927).The physicians named on the death certificate were approached by means of a postal questionnaire asking about ELDs made in each case and asked to choose the most appropriate label to describe the ELD. Response rate was 58.4%. In the vast majority of practices labelled as euthanasia, the self-reported actions of the physicians corresponded with the definition in the Belgian euthanasia legislation; practices labelled as palliative or terminal sedation lack clear correspondence with definitions of sedation as presented in existing guidelines. In these cases, an explicit life-shortening intention by means of drug administration was present in 21.6%, life shortening was estimated at more than 24 h in 51% and an explicit patient request was absentin 79.7%. Our results suggest that, unlike euthanasia,the concept of palliative or terminal sedation covers abroad range of practices in the minds of physicians. This ambiguity can be a barrier to appropriate sedation practice and indicates a need for better knowledge of the practice of palliative sedation by physicians.

Reasons, considerations, difficulties and documentation of end-of-life decisions in European intensive care units: the ETHICUS Study

DEFF Research Database (Denmark)

Sprung, C.L.; Woodcock, T.; Sjokvist, P.

2008-01-01

Objective: To evaluate physicians' reasoning, considerations and possible difficulties in end-of-life decision-making for patients in European intensive care units (ICUs). Design: A prospective observational study. Setting: Thirty-seven ICUs in 17 European countries. Patients and participants...... for, considerations in, and difficulties with end-of-life decision-making was germane in each case as it arose. Overall, 2,134 (69%) of the decisions were documented in the medical record, with inter-regional differences in documentation practice. Primary reasons given by physicians for the decision......: A total of 3,086 patients for whom an end-of-life decision was taken between January 1999 and June 2000. The dataset excludes patients who died after attempts at cardiopulmonary resuscitation and brain-dead patients. Measurements and results: Physicians indicated which of a pre-determined set of reasons...

Life-history evolution and mitogenomic phylogeny of caecilian amphibians.

Science.gov (United States)

San Mauro, Diego; Gower, David J; Müller, Hendrik; Loader, Simon P; Zardoya, Rafael; Nussbaum, Ronald A; Wilkinson, Mark

2014-04-01

We analyze mitochondrial genomes to reconstruct a robust phylogenetic framework for caecilian amphibians and use this to investigate life-history evolution within the group. Our study comprises 45 caecilian mitochondrial genomes (19 of them newly reported), representing all families and 27 of 32 currently recognized genera, including some for which molecular data had never been reported. Support for all relationships in the inferred phylogenetic tree is high to maximal, and topology tests reject all investigated alternatives, indicating an exceptionally robust molecular phylogenetic framework of caecilian evolution consistent with current morphology-based supraspecific classification. We used the mitogenomic phylogenetic framework to infer ancestral character states and to assess correlation among three life-history traits (free-living larvae, viviparity, specialized pre-adult or vernal teeth), each of which occurs only in some caecilian species. Our results provide evidence that an ancestor of the Seychelles caecilians abandoned direct development and re-evolved a free-living larval stage. This study yields insights into the concurrent evolution of direct development and of vernal teeth in an ancestor of Teresomata that likely gave rise to skin-feeding (maternal dermatophagy) behavior and subsequently enabled evolution of viviparity, with skin feeding possibly a homologous precursor of oviduct feeding in viviparous caecilians. Copyright © 2014 Elsevier Inc. All rights reserved.

Hope Amidst Hopelessness: Life Histories of Illiterate Oraon Tribal Women in Jharkhand, India

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Minz, Nijhar Jharia

2012-01-01

This interpretive study asked the question: "What education and literacy insights can be gained from the studies of the life stories of illiterate Oraon women in Jharkhand, India?" Life history methodology was used to gain insights into the lived experiences of illiterate women. I hoped to provide meaning and give voice to the voiceless.…

Niche-driven evolution of metabolic and life-history strategies in natural and domesticated populations of Saccharomyces cerevisiae

Directory of Open Access Journals (Sweden)

Sicard Delphine

2009-12-01

Full Text Available Abstract Background Variation of resource supply is one of the key factors that drive the evolution of life-history strategies, and hence the interactions between individuals. In the yeast Saccharomyces cerevisiae, two life-history strategies related to different resource utilization have been previously described in strains from different industrial origins. In this work, we analyzed metabolic traits and life-history strategies in a broader collection of yeast strains sampled in various ecological niches (forest, human body, fruits, laboratory and industrial environments. Results By analysing the genetic and plastic variation of six life-history and three metabolic traits, we showed that S. cerevisiae populations harbour different strategies depending on their ecological niches. On one hand, the forest and laboratory strains, referred to as extreme "ants", reproduce quickly, reach a large carrying capacity and a small cell size in fermentation, but have a low reproduction rate in respiration. On the other hand, the industrial strains, referred to as extreme "grasshoppers", reproduce slowly, reach a small carrying capacity but have a big cell size in fermentation and a high reproduction rate in respiration. "Grasshoppers" have usually higher glucose consumption rate than "ants", while they produce lower quantities of ethanol, suggesting that they store cell resources rather than secreting secondary products to cross-feed or poison competitors. The clinical and fruit strains are intermediate between these two groups. Conclusions Altogether, these results are consistent with a niche-driven evolution of S. cerevisiae, with phenotypic convergence of populations living in similar habitat. They also revealed that competition between strains having contrasted life-history strategies ("ants" and "grasshoppers" seems to occur at low frequency or be unstable since opposite life-history strategies appeared to be maintained in distinct ecological niches.

Positive predictors of quality of life for postpartum mothers with a history of childhood maltreatment.

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Irwin, Jessica L; Beeghly, Marjorie; Rosenblum, Katherine L; Muzik, Maria

2016-12-01

The postpartum period brings a host of biopsychosocial, familial, and economic changes, which may be challenging for new mothers, especially those with trauma histories. Trauma-exposed women are at heightened risk for psychiatric symptomatology and reduced quality of life. The current study sought to evaluate whether a set of hypothesized promotive factors assessed during the first 18 months postpartum (positive parenting, family cohesion, and maternal resilience) are associated with life satisfaction in this population, after controlling for income and postpartum psychiatric symptoms. Analyses were based on data collected for 266 mother-infant dyads from a longitudinal cohort study, Maternal Anxiety during the Childbearing Years (MACY), of women oversampled for childhood maltreatment history. Hierarchical linear regression was used to evaluate the study hypotheses. Consistent with prior work, greater postpartum psychiatric symptoms and less income predicted poor perceptions of life quality. In hierarchical regressions controlling for income and psychiatric symptoms, positive parenting and family cohesion predicted unique variance in mothers' positive perceptions of life quality, and resilience was predictive beyond all other factors. Factors from multiple levels of analysis (maternal, dyadic, and familial) may serve as promotive factors predicting positive perceptions of life quality among women with childhood trauma histories, even those struggling with high levels of psychiatric or economic distress.

Age-dependent male mating tactics in a spider mite-A life-history perspective.

Science.gov (United States)

Sato, Yukie; Rühr, Peter T; Schmitz, Helmut; Egas, Martijn; Blanke, Alexander

2016-10-01

Males often fight with rival males for access to females. However, some males display nonfighting tactics such as sneaking, satellite behavior, or female mimicking. When these mating tactics comprise a conditional strategy, they are often thought to be explained by resource holding potential (RHP), that is, nonfighting tactics are displayed by less competitive males who are more likely to lose a fight. The alternative mating tactics, however, can also be explained by life-history theory, which predicts that young males avoid fighting, regardless of their RHP, if it pays off to wait for future reproduction. Here, we test whether the sneaking tactic displayed by young males of the two-spotted spider mite can be explained by life-history theory. We tested whether young sneaker males survive longer than young fighter males after a bout of mild or strong competition with old fighter males. We also investigated whether old males have a more protective outer skin-a possible proxy for RHP-by measuring cuticle hardness and elasticity using nanoindentation. We found that young sneaker males survived longer than young fighter males after mild male competition. This difference was not found after strong male competition, which suggests that induction of sneaking tactic is affected by male density. Hardness and elasticity of the skin did not vary with male age. Given that earlier work could also not detect morphometric differences between fighter and sneaker males, we conclude that there is no apparent increase in RHP with age in the mite and age-dependent male mating tactics in the mite can be explained only by life-history theory. Because it is likely that fighting incurs a survival cost, age-dependent alternative mating tactics may be explained by life-history theory in many species when reproduction of old males is a significant factor in fitness.

End-of-life decision-making for children with severe developmental disabilities: The parental perspective

NARCIS (Netherlands)

Zaal-Schuller, I. H.; de Vos, M. A.; Ewals, F. V. P. M.; van Goudoever, J. B.; Willems, D. L.

2016-01-01

The objectives of this integrative review were to understand how parents of children with severe developmental disorders experience their involvement in end-of-life decision-making, how they prefer to be involved and what factors influence their decisions. We searched MEDLINE, EMBASE, CINAHL and

Decision Making Among Older Adults at the End of Life: A Theoretical Perspective.

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Romo, Rafael D; Dawson-Rose, Carol S; Mayo, Ann M; Wallhagen, Margaret I

Understanding changes in decision making among older adults across time is important for health care providers. We examined how older adults with a limited prognosis used their perception of prognosis and health in their decision-making processes and related these findings to prospect theory. The theme of decision making in the context of ambiguity emerged, reflecting how participants used both prognosis and health to value choices, a behavior not fully captured by prospect theory. We propose an extension of the theory that can be used to better visualize decision making at this unique time of life among older adults.

Population dynamics, life-history traits of and habitat use by two ...

African Journals Online (AJOL)

Population dynamics and life-history traits of two sympatric nothobranchiid killifishes, Epiplatys bifasciatus and E. spilargyreius, were studied for 24 months in an intermittent stream in the Kainji Lake Basin, Nigeria. Epiplatys bifasciatus was more abundant throughout the study period, but monthly abundance of both species ...

Human Life History Strategies.

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Chua, Kristine J; Lukaszewski, Aaron W; Grant, DeMond M; Sng, Oliver

2017-01-01

Human life history (LH) strategies are theoretically regulated by developmental exposure to environmental cues that ancestrally predicted LH-relevant world states (e.g., risk of morbidity-mortality). Recent modeling work has raised the question of whether the association of childhood family factors with adult LH variation arises via (i) direct sampling of external environmental cues during development and/or (ii) calibration of LH strategies to internal somatic condition (i.e., health), which itself reflects exposure to variably favorable environments. The present research tested between these possibilities through three online surveys involving a total of over 26,000 participants. Participants completed questionnaires assessing components of self-reported environmental harshness (i.e., socioeconomic status, family neglect, and neighborhood crime), health status, and various LH-related psychological and behavioral phenotypes (e.g., mating strategies, paranoia, and anxiety), modeled as a unidimensional latent variable. Structural equation models suggested that exposure to harsh ecologies had direct effects on latent LH strategy as well as indirect effects on latent LH strategy mediated via health status. These findings suggest that human LH strategies may be calibrated to both external and internal cues and that such calibrational effects manifest in a wide range of psychological and behavioral phenotypes.

Human Life History Strategies

Directory of Open Access Journals (Sweden)

Kristine J. Chua

2016-12-01

Full Text Available Human life history (LH strategies are theoretically regulated by developmental exposure to environmental cues that ancestrally predicted LH-relevant world states (e.g., risk of morbidity–mortality. Recent modeling work has raised the question of whether the association of childhood family factors with adult LH variation arises via (i direct sampling of external environmental cues during development and/or (ii calibration of LH strategies to internal somatic condition (i.e., health, which itself reflects exposure to variably favorable environments. The present research tested between these possibilities through three online surveys involving a total of over 26,000 participants. Participants completed questionnaires assessing components of self-reported environmental harshness (i.e., socioeconomic status, family neglect, and neighborhood crime, health status, and various LH-related psychological and behavioral phenotypes (e.g., mating strategies, paranoia, and anxiety, modeled as a unidimensional latent variable. Structural equation models suggested that exposure to harsh ecologies had direct effects on latent LH strategy as well as indirect effects on latent LH strategy mediated via health status. These findings suggest that human LH strategies may be calibrated to both external and internal cues and that such calibrational effects manifest in a wide range of psychological and behavioral phenotypes.

Shared decision making in Brazil: history and current discussion.

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Abreu, Mirhelen Mendes de; Battisti, Raphael; Martins, Rachel Samhan; Baumgratz, Thiago Dias; Cuziol, Mirella

2011-01-01

There is no SDM in clinical practice in Brazil. The first steps have been taken towards research and tool development recently. Likewise, our society is starting to get involved with decision making in health care. This paper aims to offer an overview of the Brazilian health system history, its values, and its influence on SDM. The participative social control concept is introduced as a result of the movement against the dictatorship era. In addition, the influence of social changes on the Medical Ethical Code is delineated. SDM state of the art in Brazil is also discussed and the challenges to implement it on clinical practice are described. Regardless the challenges, it is possible to make a positive assessment of SDM in Brazil. 2011. Published by Elsevier GmbH.

Leadership in the history-making decisions of European integration

DEFF Research Database (Denmark)

Beach, Derek

2007-01-01

Within EU studies, there has been an increasing recognition that the celebrated ‘big bangs’ of integration do not materialize by themselves. History-making decisions like constitutional negotiations within intergovernmental conferences (IGCs) are not what can be termed ‘spot markets’, [1] where......) and their impact, with the inevitable over/underestimation of influence depending upon how the author’s take on the person. In recent years the concept of leadership has been utilized in a more systematic fashion both within political science / international relations more generally, and more specifically within...... EU studies. We have seen the use of principal-agent theorizing on leadership, with scholars looking at legislative politics (Fiorina and Shepsle), executive politics and delegation (Pollack, Tallberg), along with the broader IR literature on regime creation and change and interstate negotiations...

Making decisions at the end of life when caring for a person with dementia: a literature review to explore the potential use of heuristics in difficult decision-making.

Science.gov (United States)

Mathew, R; Davies, N; Manthorpe, J; Iliffe, S

2016-07-19

Decision-making, when providing care and treatment for a person with dementia at the end of life, can be complex and challenging. There is a lack of guidance available to support practitioners and family carers, and even those experienced in end of life dementia care report a lack of confidence in decision-making. It is thought that the use of heuristics (rules of thumb) may aid decision-making. The aim of this study is to identify whether heuristics are used in end of life dementia care, and if so, to identify the context in which they are being used. A narrative literature review was conducted taking a systematic approach to the search strategy, using the Centre for Reviews and Dissemination guidelines. Rapid appraisal methodology was used in order to source specific and relevant literature regarding the use of heuristics in end of life dementia care. A search using terms related to dementia, palliative care and decision-making was conducted across 4 English language electronic databases (MEDLINE, EMBASE, PsycINFO and CINAHL) in 2015. The search identified 12 papers that contained an algorithm, guideline, decision tool or set of principles that we considered compatible with heuristic decision-making. The papers addressed swallowing and feeding difficulties, the treatment of pneumonia, management of pain and agitation, rationalising medication, ending life-sustaining treatment, and ensuring a good death. The use of heuristics in palliative or end of life dementia care is not described in the research literature. However, this review identified important decision-making principles, which are largely a reflection of expert opinion. These principles may have the potential to be developed into simple heuristics that could be used in practice. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

State-dependent life-history strategies : A long-term study on oystercatchers

NARCIS (Netherlands)

van de Pol, Martijn

2006-01-01

The research described in this thesis is part of a long-term field study on free-living Oystercatchers (Haematopus ostralegus), on the Dutch Wadden Sea island of Schiermonnikoog.The study was started in 1983 by Jan Hulscher, and since then a lineage of PhDstudents has investigated life-history

Life-history traits of the northwest European flora : The LEDA database

NARCIS (Netherlands)

Knevel, IC; Bekker, RM; Bakker, JP; Kleyer, M

An international group of scientists is building a 'trait base', an open internet database of life-history traits of the Northwest European flora (LEDA) that can be used as a tool in planning, in nature conservation and restoration, and in other applied research. The species-trait matrix will

An expandable software model for collaborative decision making during the whole building life cycle

International Nuclear Information System (INIS)

Papamichael, K.; Pal, V.; Bourassa, N.; Loffeld, J.; Capeluto, G.

2000-01-01

Decisions throughout the life cycle of a building, from design through construction and commissioning to operation and demolition, require the involvement of multiple interested parties (e.g., architects, engineers, owners, occupants and facility managers). The performance of alternative designs and courses of action must be assessed with respect to multiple performance criteria, such as comfort, aesthetics, energy, cost and environmental impact. Several stand-alone computer tools are currently available that address specific performance issues during various stages of a building's life cycle. Some of these tools support collaboration by providing means for synchronous and asynchronous communications, performance simulations, and monitoring of a variety of performance parameters involved in decisions about a building during building operation. However, these tools are not linked in any way, so significant work is required to maintain and distribute information to all parties. In this paper we describe a software model that provides the data management and process control required for collaborative decision making throughout a building's life cycle. The requirements for the model are delineated addressing data and process needs for decision making at different stages of a building's life cycle. The software model meets these requirements and allows addition of any number of processes and support databases over time. What makes the model infinitely expandable is that it is a very generic conceptualization (or abstraction) of processes as relations among data. The software model supports multiple concurrent users, and facilitates discussion and debate leading to decision making. The software allows users to define rules and functions for automating tasks and alerting all participants to issues that need attention. It supports management of simulated as well as real data and continuously generates information useful for improving performance prediction and

Procrastination as a Fast Life History Strategy

Directory of Open Access Journals (Sweden)

Bin-Bin Chen

2016-02-01

Full Text Available Research has revealed that procrastination—the purposive delay of an intended course of action—is a maladaptive behavior. However, by drawing on an evolutionary life history (LF approach, the present study proposes that procrastination may be an adaptive fast LF strategy characterized by prioritizing immediate benefits with little regard to long-term consequences. A total of 199 undergraduate students completed measures of procrastination and future orientation and the Mini-K scale, which measures the slow LF strategy. Structural equation modeling revealed that, as predicted, procrastination was negatively associated with a slow LF strategy both directly and indirectly through the mediation of future orientation. These results define the fast LF origin of procrastination.

Life-history differences favor evolution of male dimorphism in competitive games.

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Smallegange, Isabel M; Johansson, Jacob

2014-02-01

Many species exhibit two discrete male morphs: fighters and sneakers. Fighters are large and possess weapons but may mature slowly. Sneakers are small and have no weapons but can sneak matings and may mature quickly to start mating earlier in life than fighters. However, how differences in competitive ability and life history interact to determine male morph coexistence has not yet been investigated within a single framework. Here we integrate demography and game theory into a two-sex population model to study the evolution of strategies that result in the coexistence of fighters and sneakers. We incorporate differences in maturation time between the morphs and use a mating-probability matrix analogous to the classic hawk-dove game. Using adaptive dynamics, we show that male dimorphism evolves more easily in our model than in classic game theory approaches. Our results also revealed an interaction between life-history differences and sneaker competitiveness, which shows that demography and competitive games should be treated as interlinked mechanisms to understand the evolution of male dimorphism. Applying our approach to empirical data on bulb mites (Rhizoglyphus robini), coho salmon (Oncorhynchus kisutch), and bullhorned dung beetles (Onthophagus taurus) indicates that observed occurrences of male dimorphism are in general agreement with model predictions.

Relationship of External Influence to Parental Distress in Decision Making Regarding Children with a Life-Threatening Illness

Science.gov (United States)

Luce, Mary Frances; Nelson, Robert M.

2011-01-01

Objective To examine the relationship of external influence to parental distress when making a decision about research or treatment for a child with a life-threatening illness and to test potential moderators of this relationship. Methods Parents (n = 219) who made a decision about research or treatment for a child completed measures of external influence, distress, decision-making preference, and coping. Results More external influence was associated with more hostility, uncertainty, and confusion. Decision-making preference and coping style moderated the relationship between external influence and distress: More external influence was associated with more distress when decision-making preference was low and task-focused coping was high. Conclusions External influence appears to be related to distress in parents making research and treatment decisions for children with life-threatening illnesses. However, it is important to consider parent characteristics, such as decision-making preference and coping style, when examining the effects of contextual factors on distress during decision making. PMID:21693541

Relationship of external influence to parental distress in decision making regarding children with a life-threatening illness.

Science.gov (United States)

Miller, Victoria A; Luce, Mary Frances; Nelson, Robert M

2011-01-01

To examine the relationship of external influence to parental distress when making a decision about research or treatment for a child with a life-threatening illness and to test potential moderators of this relationship. Parents (n = 219) who made a decision about research or treatment for a child completed measures of external influence, distress, decision-making preference, and coping. More external influence was associated with more hostility, uncertainty, and confusion. Decision-making preference and coping style moderated the relationship between external influence and distress: More external influence was associated with more distress when decision-making preference was low and task-focused coping was high. External influence appears to be related to distress in parents making research and treatment decisions for children with life-threatening illnesses. However, it is important to consider parent characteristics, such as decision-making preference and coping style, when examining the effects of contextual factors on distress during decision making.

Optimal foraging and diel vertical migration in a life history model

DEFF Research Database (Denmark)

Sainmont, Julie; Andersen, Ken Haste; Visser, Andre

in the model, unsuited for life history modeling. We propose a method based on optimal foraging theory to take into account the emergent feeding rates as a function of the copepod metabolic cost, latitude, time and predation. We predict that copepods will balance their growth rate and mortality, playing a safe...

The Juvenile Transition: A Developmental Switch Point in Human Life History

Science.gov (United States)

Del Giudice, Marco; Angeleri, Romina; Manera, Valeria

2009-01-01

This paper presents a new perspective on the transition from early to middle childhood (i.e., human juvenility), investigated in an integrative evolutionary framework. Juvenility is a crucial life history stage, when social learning and interaction with peers become central developmental functions; here it is argued that the "juvenile transition"…

The influence of life-history strategy on genetic differentiation and lineage divergence in darters (Percidae: Etheostomatinae).

Science.gov (United States)

Fluker, Brook L; Kuhajda, Bernard R; Harris, Phillip M

2014-11-01

Recent studies determined that darters with specialized breeding strategies can exhibit deep lineage divergence over fine geographic scales without apparent physical barriers to gene flow. However, the extent to which intrinsic characteristics interact with extrinsic factors to influence population divergence and lineage diversification in darters is not well understood. This study employed comparative phylogeographic and population genetic methods to investigate the influence of life history on gene flow, dispersal ability, and lineage divergence in two sympatric sister darters with differing breeding strategies. Our results revealed highly disparate phylogeographic histories, patterns of genetic structure, and dispersal abilities between the two species suggesting that life history may contribute to lineage diversification in darters, especially by limiting dispersal among large river courses. Both species also showed striking differences in demographic history, indicating that extrinsic factors differentially affected each species during the Pleistocene. Collectively, our results indicate that intrinsic and extrinsic factors have influenced levels of gene flow among populations within both species examined. However, we suggest that life-history strategy may play a more important role in lineage diversification in darters than previously appreciated, a finding that has potentially important implications for understanding diversification of the rich North American freshwater fish fauna. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

Comparative life cycles and life histories of North American Rhabdias spp. (Nematoda: Rhabdiasidae): lungworms from snakes and anurans.

Science.gov (United States)

Langford, Gabriel J; Janovy, John

2009-10-01

The present study used experimental infections to compare the life cycles and life histories of 6 Rhabdias spp. infecting snakes and anurans. Free-living development of anuran lungworms was primarily limited to heterogonic reproduction, and females utilized matricidal endotoky exclusively, whereas snake lungworms primarily reproduced homogonically and, when heterogonic reproduction occurred, females used a combination of releasing eggs and matricidal endotoky. Infective snake lungworms survived for longer periods in fresh water compared to anuran worms. Infective anuran lungworms penetrated into the skin of frogs and toads; few infections resulted from per os infections. In contrast, snake lungworms were unable to penetrate skin; instead, infective juveniles penetrated into snake esophageal tissue during per os infections. Despite separate points of entry, anuran and snake lungworms both migrated and developed in the fascia, eventually penetrating into the body cavity of the host. Worms molted to adulthood inside the body cavity and subsequently penetrated into the host's lungs, where they fed on blood while becoming gravid. Adult lungworm survival varied among lungworm species, but, in general, snake lungworms were longer lived than anuran worms. Anuran lungworms were poorly suited for transmission via transport hosts, whereas snake lungworms were consistently capable of establishing infections using transport hosts. Overall, these observations suggest that snake and anuran lungworms have discrepant life cycles and life history strategies.

Confronting Uncertainty in Life Cycle Assessment Used for Decision Support

DEFF Research Database (Denmark)

Herrmann, Ivan Tengbjerg; Hauschild, Michael Zwicky; Sohn, Michael D.

2014-01-01

the decision maker (DM) in making the best possible choice for the environment. At present, some DMs do not trust the LCA to be a reliable decisionsupport tool—often because DMs consider the uncertainty of an LCA to be too large. The standard evaluation of uncertainty in LCAs is an ex-post approach that can...... regarding which type of LCA study to employ for the decision context at hand. This taxonomy enables the derivation of an LCA classification matrix to clearly identify and communicate the type of a given LCA. By relating the LCA classification matrix to statistical principles, we can also rank the different......The aim of this article is to help confront uncertainty in life cycle assessments (LCAs) used for decision support. LCAs offer a quantitative approach to assess environmental effects of products, technologies, and services and are conducted by an LCA practitioner or analyst (AN) to support...

End-of-life decisions in perinatal care. A view from health-care providers

Directory of Open Access Journals (Sweden)

Patricia Grether

2015-11-01

Full Text Available Objective. To examine the opinions of a perinatal health team regarding decisions related to late termination of pregnancy and severely ill newborns. Materials and Methods. An anonymous questionnaire was administered to physicians, social workers, and nurses in perinatal care. Differences were evaluated using the chi square and Student’s t tests. Results. When considering severely ill fetuses and newborns, 82% and 93% of participants, respectively, opted for providing palliative care, whereas 18% considered feticide as an alter- native. Those who opted for palliative care aimed to diminish suffering and those who opted for intensive care intended to protect life or sanctity of life. There was poor knowledge about the laws that regulate these decisions. Conclusions. Although there is no consensus on what decisions should be taken with severely ill fetuses or neonates, most participants considered palliative care as the first option, but feticide or induced neonatal death was not ruled out.

Learning in Life History - psycho-societal interpretation of biographies

DEFF Research Database (Denmark)

Olesen, Henning Salling

2008-01-01

Taking its point of departure from some critical remarks about some of the most important recent theorizing of learning, this article presents an alternative framework for theorizing learning as a subjective process in a social and societal context, based on life history research. The key concepts...... of subjectivity and experience, derived from European critical theory, are briefly introduced with respect to their intellectual background. Based on examples from the author’s research into the professional learning, the article outlines the implications of these concepts in relation to an understanding...... of emotional aspects of learning in everyday life and to an understanding of knowledge. The pivotal role of language use and language socialisation is explained in brief, and a psychodynamic complement to a language game concept of language use is developed....

Life history, immunity, Peto's paradox and tumours in birds.

Science.gov (United States)

Møller, A P; Erritzøe, J; Soler, J J

2017-05-01

Cancer and tumours may evolve in response to life-history trade-offs between growth and duration of development on one hand, and between growth and maintenance of immune function on the other. Here, we tested whether (i) bird species with slow developmental rates for their body size experience low incidence of tumours because slow development allows for detection of rapid proliferation of cell lineages. We also test whether (ii) species with stronger immune response during development are more efficient at detecting tumour cells and hence suffer lower incidence of tumours. Finally, we tested Peto's paradox, that there is a positive relationship between tumour incidence and body mass. We used information on developmental rates and body mass from the literature and of tumour incidence (8468 birds) and size of the bursa of Fabricius for 7659 birds brought to a taxidermist in Denmark. We found evidence of the expected negative relationship between incidence of tumours and developmental rates and immunity after controlling for the positive association between tumour incidence and body size. These results suggest that evolution has modified the incidence of tumours in response to life history and that Peto's paradox may be explained by covariation between body mass, developmental rates and immunity. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Death Penalty Decisions: Instruction Comprehension, Attitudes, and Decision Mediators.

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Patry, Marc W; Penrod, Steven D

2013-01-01

A primary goal of this research was to empirically evaluate a set of assumptions, advanced in the Supreme Court's ruling in Buchanan v. Angelone (1998), about jury comprehension of death penalty instructions. Further, this research examined the use of evidence in capital punishment decision making by exploring underlying mediating factors upon which death penalty decisions may be based. Manipulated variables included the type of instructions and several variations of evidence. Study 1 was a paper and pencil study of 245 undergraduate mock jurors. The experimental design was an incomplete 4×2×2×2×2 factorial model resulting in 56 possible conditions. Manipulations included four different types of instructions, presence of a list of case-specific mitigators to accompany the instructions, and three variations in the case facts: age of the defendant, bad prior record, and defendant history of emotional abuse. Study 2 was a fully-crossed 2×2×2×2×2 experiment with four deliberating mock juries per cell. Manipulations included jury instructions (original or revised), presence of a list of case-specific mitigators, defendant history of emotional abuse, bad prior record, and heinousness of the crime. The sample of 735 jury-eligible participants included 130 individuals who identified themselves as students. Participants watched one of 32 stimulus videotapes based on a replication of a capital sentencing hearing. The present findings support previous research showing low comprehension of capital penalty instructions. Further, we found that higher instruction comprehension was associated with higher likelihood of issuing life sentence decisions. The importance of instruction comprehension is emphasized in a social cognitive model of jury decision making at the sentencing phase of capital cases.

Sexual dysfunction risk and quality of life among women with a history of sexual abuse.

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Carreiro, Andrea V; Micelli, Ligia P; Sousa, Maria H; Bahamondes, Luis; Fernandes, Arlete

2016-09-01

To assess scores for sexual dysfunction risk and quality of life in a cohort of women in Brazil who had a history of sexual abuse. The present study was a secondary analysis of a cross-sectional study conducted between February 1, 2011 and May 31, 2012. Women aged 18-49years attending a family planning clinic at the University of Campinas, Brazil, who were in a heterosexual relationship and reported engaging in sexual intercourse in the 4weeks prior to the study were enrolled. Participants were asked to complete the World Health Organization Quality of Life Questionnaire, Abbreviated Version, and the Female Sexual Function Index (FSFI) questionnaire. Data were grouped based on a history of sexual abuse. An FSFI score of no higher than 26.55 was considered the cut off for sexual dysfunction. The prevalence of FSFI-defined sexual dysfunction was higher in participants with a history of sexual abuse (Phistory of sexual abuse had significantly lower scores across all quality of life domains. Increased risk of sexual dysfunction among women with a history of sexual abuse suggests potential problems in the sex lives of individuals in this population. Healthcare professionals should be alert to this diagnosis. Copyright © 2016 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

Some Life History Narratives of Religious Education Coordinators in Catholic Schools

Science.gov (United States)

Rymarz, Richard; Belmonte, Angelo

2014-01-01

This paper seeks to gain a better understanding of religious education coordinators (RECs) in contemporary Catholic schools. This is done by using life history narratives to explore how participants came to be RECs. This study takes place in a wider cultural context that sees strong religious commitment, manifested by taking leadership positions…

The Psychology and Neuroscience of Financial Decision Making.

Science.gov (United States)

Frydman, Cary; Camerer, Colin F

2016-09-01

Financial decisions are among the most important life-shaping decisions that people make. We review facts about financial decisions and what cognitive and neural processes influence them. Because of cognitive constraints and a low average level of financial literacy, many household decisions violate sound financial principles. Households typically have underdiversified stock holdings and low retirement savings rates. Investors overextrapolate from past returns and trade too often. Even top corporate managers, who are typically highly educated, make decisions that are affected by overconfidence and personal history. Many of these behaviors can be explained by well-known principles from cognitive science. A boom in high-quality accumulated evidence-especially how practical, low-cost 'nudges' can improve financial decisions-is already giving clear guidance for balanced government regulation. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Current health and preferences for life-prolonging treatments: an application of prospect theory to end-of-life decision making.

Science.gov (United States)

Winter, Laraine; Parker, Barbara

2007-10-01

As a substantial body of research attests, the acceptability of life-prolonging treatment (e.g., tube feeding) tends to be greater among people in worse health than among healthier ones. Because a decision for or against a life-prolonging treatment represents a choice between two prospects-life (usually in poor health) and death-we propose a decision model, Prospect Theory, as a theoretical account of this phenomenon. Prospect Theory postulates that pairs of distant prospects are less distinguishable than pairs of closer ones. Thus, to healthy individuals, the prospects of death and life in poor health would both be remote, and therefore, the distinction between them, small. To less healthy individuals, however, the difference between the same pairs of prospects would appear greater, and therefore, life-prolonging treatment may be more acceptable. In a cross-sectional study of 304 community-dwelling people, aged 60 years and over in the Philadelphia area, USA, preferences for 4 life-prolonging treatments in 9 health scenarios were examined in relation to participants' current health, operationalized as number of deficits in physical functioning. As predicted, less healthy people expressed stronger preferences for all life-prolonging treatments compared with healthier ones, with differences greatest in the worse-health scenarios. Preferences also varied by health scenario, with any treatment preferred in the better health scenarios. Treatment preferences did not differ by type of treatment, depressed mood or any demographic characteristic except race, with African-Americans expressing stronger treatment preferences. Implications for advance care planning are discussed.

From Asia Minor to Greece: History, Memory and Migration

Directory of Open Access Journals (Sweden)

Emine Yeşim Bedlek

2017-08-01

Full Text Available History and memory studies are among the most controversial topics of our era. While the official history is made up of state discourse, personal history reaches the reader through the memories of the individuals. The events that leave traces in memory are passed on to future generations by oral history studies. The pasts of individuals whose individual experiences are unpacked by the oral historians give us more detailed information about the traumas individuals. Yiannis Karatzoglou also documents his past in order to pass the traumas of migration due to the Lausanne Convention signed in 1923 between Greece and Turkey. This study examines the impact of the social, cultural and political decisions of Turkey and Greece on individuals through the life story of Yiannis in the light of history and memory.

Movements of Blue Sharks (Prionace glauca) across Their Life History

Science.gov (United States)

Vandeperre, Frederic; Aires-da-Silva, Alexandre; Fontes, Jorge; Santos, Marco; Serrão Santos, Ricardo; Afonso, Pedro

2014-01-01

Spatial structuring and segregation by sex and size is considered to be an intrinsic attribute of shark populations. These spatial patterns remain poorly understood, particularly for oceanic species such as blue shark (Prionace glauca), despite its importance for the management and conservation of this highly migratory species. This study presents the results of a long-term electronic tagging experiment to investigate the migratory patterns of blue shark, to elucidate how these patterns change across its life history and to assess the existence of a nursery area in the central North Atlantic. Blue sharks belonging to different life stages (n = 34) were tracked for periods up to 952 days during which they moved extensively (up to an estimated 28.139 km), occupying large parts of the oceanic basin. Notwithstanding a large individual variability, there were pronounced differences in movements and space use across the species' life history. The study provides strong evidence for the existence of a discrete central North Atlantic nursery, where juveniles can reside for up to at least 2 years. In contrast with previously described nurseries of coastal and semi-pelagic sharks, this oceanic nursery is comparatively vast and open suggesting that shelter from predators is not its main function. Subsequently, male and female blue sharks spatially segregate. Females engage in seasonal latitudinal migrations until approaching maturity, when they undergo an ontogenic habitat shift towards tropical latitudes. In contrast, juvenile males generally expanded their range southward and apparently displayed a higher degree of behavioural polymorphism. These results provide important insights into the spatial ecology of pelagic sharks, with implications for the sustainable management of this heavily exploited shark, especially in the central North Atlantic where the presence of a nursery and the seasonal overlap and alternation of different life stages coincides with a high fishing

Life-history and ecological correlates of population change in Dutch breeding birds.

NARCIS (Netherlands)

Turnhout, van C.A.M.; Foppen, R.P.B.; Leuven, R.S.E.W.; Strien, van A.J.; Siepel, H.

2010-01-01

Predicting relative extinction risks of animals has become a major challenge in conservation biology. Identifying life-history and ecological traits related to the decline of species helps understand what causes population decreases and sets priorities for conservation action. Here, we use Dutch

Phenoloxidase activity in the infraorder Isoptera: unraveling life-history correlates of immune investment

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Rosengaus, Rebeca B.; Reichheld, Jennifer L.

2016-02-01

Within the area of ecological immunology, the quantification of phenoloxidase (PO) activity has been used as a proxy for estimating immune investment. Because termites have unique life-history traits and significant inter-specific differences exist regarding their nesting and foraging habits, comparative studies on PO activity can shed light on the general principles influencing immune investment against the backdrop of sociality, reproductive potential, and gender. We quantified PO activity across four termite species ranging from the phylogenetically basal to the most derived, each with their particular nesting/foraging strategies. Our data indicate that PO activity varies across species, with soil-dwelling termites exhibiting significantly higher PO levels than the above-ground wood nester species which in turn have higher PO levels than arboreal species. Moreover, our comparative approach suggests that pathogenic risks can override reproductive potential as a more important driver of immune investment. No gender-based differences in PO activities were recorded. Although termite PO activity levels vary in accordance with a priori predictions made from life-history theory, our data indicate that nesting and foraging strategies (and their resulting pathogenic pressures) can supersede reproductive potential and other life-history traits in influencing investment in PO. Termites, within the eusocial insects, provide a unique perspective for inferring how different ecological pressures may have influenced immune function in general and their levels of PO activity, in particular.

Quantifying the life-history response to increased male exposure in female Drosophila melanogaster.

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Edward, Dominic A; Fricke, Claudia; Gerrard, Dave T; Chapman, Tracey

2011-02-01

Precise estimates of costs and benefits, the fitness economics, of mating are of key importance in understanding how selection shapes the coevolution of male and female mating traits. However, fitness is difficult to define and quantify. Here, we used a novel application of an established analytical technique to calculate individual- and population-based estimates of fitness-including those sensitive to the timing of reproduction-to measure the effects on females of increased exposure to males. Drosophila melanogaster females were exposed to high and low frequencies of contact with males, and life-history traits for each individual female were recorded. We then compared different fitness estimates to determine which of them best described the changes in life histories. We predicted that rate-sensitive estimates would be more accurate, as mating influences the rate of offspring production in this species. The results supported this prediction. Increased exposure to males led to significantly decreased fitness within declining but not stable or increasing populations. There was a net benefit of increased male exposure in expanding populations, despite a significant decrease in lifespan. The study shows how a more accurate description of fitness, and new insights can be achieved by considering individual life-history strategies within the context of population growth. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

Determination of the appropriate use of pavement surface history in the KDOT life-cycle analysis process.

Science.gov (United States)

2008-09-01

The primary objective of this study was to evaluate KDOTs pavement surfacing history and recommend : whether or not the departments life-cycle cost analysis (LCCA) procedure should include a surfacing history : component, and, if so, how the LC...

Life history of the sand fly vector Lutzomyia cruciata in laboratory conditions.

Science.gov (United States)

Castillo, A; Serrano, A K; Mikery, O F; Pérez, J

2015-12-01

Lutzomyia cruciata Coquillet (Diptera: Psychodidae: Phlebotominae) is a potential vector of Leishmania sp.; its geographical distribution in Mexico is widespread, but its life history is unknown. The present study gives relevant information on the life cycle, morphology, survival and reproduction of Lu. cruciata observed over successive generations under laboratory conditions. Seven successive generations were produced. A total of 975 adults were obtained in a sexual proportion of 1.1 : 1 (female : male). Each Lu. cruciata female produced 20.7 eggs and 1.9 adults, approximately, with a proportion of eggs per female of 2.7% (first generation) and 21.3% (second generation). The life cycle of Lu. cruciata, from egg to adult, occurred in 52.7 ± 0.52 days. The largest percentage of mortality occurred during the egg stage (48.5%) and the first larval instar (26.5%), whereas in the pupal stage mortality was the lowest (9.1%). Lutzomyia cruciata exhibits sexual dimorphism based on size, which is exhibited as of the second larval instar, males being smaller than females. The maximum survival of females and males was 10 and 15 days, respectively. An overview of the immature stages of the species made with an electronic scanning microscope is included. This paper contributes basic information on aspects of Lu. cruciata that were previously unknown related to its life history. © 2015 The Royal Entomological Society.

Effects of Healthy Aging and Mild Cognitive Impairment on a Real-Life Decision-Making Task.

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Pertl, Marie-Theres; Benke, Thomas; Zamarian, Laura; Delazer, Margarete

2017-01-01

In this study, we investigated the effects of age and of mild cognitive impairment (MCI) on decision making under risk by adopting a task representing real-life health-related situations and involving complex numerical information. Moreover, we assessed the relationship of real-life decision making to other cognitive functions such as number processing, executive functions, language, memory, and attention. For this reason, we compared the performance of 19 healthy, relatively younger adults with that of 18 healthy older adults and the performance of the 18 healthy older adults with that of 17 patients with MCI. Results indicated difficulties in real-life decision making for the healthy older adults compared with the healthy, relatively younger adults. Difficulties of patients with MCI relative to the healthy older adults arose in particular in difficult items requiring processing of frequencies and fractions. Significant effects of age and of MCI in processing frequencies were also evident in a ratio number comparison task. Decision-making performance of healthy participants and of the patient group correlated significantly with number processing. There was a further significant correlation with executive functions for the healthy participants and with reading comprehension for the patients. Our results suggest that healthy older individuals and patients with MCI make less advantageous decisions when the information is complex and high demands are put on executive functions and numerical abilities. Moreover, we show that executive functions and numerical abilities are not only essential in laboratory gambling tasks but also in more realistic and ecological decision situations within the health context.

Early life history and habitat ecology of estuarine fishes: responses to natural and human induced change

Directory of Open Access Journals (Sweden)

Kenneth Able

2015-12-01

Full Text Available Our understanding of the early life history of fishes and their habitats has proceeded from basic natural history to ecology, but we often need to return to natural history to address deficiencies in conceptual and quantitative models of ecosystems. This understanding is further limited by the complex life history of fishes and the lack of appreciation of shifting baselines in estuaries. These inadequacies are especially evident when we try to address the effects of human influences, e.g. fishing, urbanization, and climate change. Often our baselines are inadequate or inaccurate. Our work has detected these along the coasts of the U.S. in extensive time series of larval fish ingress into estuaries, studies of the effects of urbanization, and responses to catastrophes such as the BP oil spill. Long-term monitoring, especially, continues to provide critical insights

Multi-state models: metapopulation and life history analyses

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Arnason, A. N.

2004-06-01

Full Text Available Multi–state models are designed to describe populations that move among a fixed set of categorical states. The obvious application is to population interchange among geographic locations such as breeding sites or feeding areas (e.g., Hestbeck et al., 1991; Blums et al., 2003; Cam et al., 2004 but they are increasingly used to address important questions of evolutionary biology and life history strategies (Nichols & Kendall, 1995. In these applications, the states include life history stages such as breeding states. The multi–state models, by permitting estimation of stage–specific survival and transition rates, can help assess trade–offs between life history mechanisms (e.g. Yoccoz et al., 2000. These trade–offs are also important in meta–population analyses where, for example, the pre–and post–breeding rates of transfer among sub–populations can be analysed in terms of target colony distance, density, and other covariates (e.g., Lebreton et al. 2003; Breton et al., in review. Further examples of the use of multi–state models in analysing dispersal and life–history trade–offs can be found in the session on Migration and Dispersal. In this session, we concentrate on applications that did not involve dispersal. These applications fall in two main categories: those that address life history questions using stage categories, and a more technical use of multi–state models to address problems arising from the violation of mark–recapture assumptions leading to the potential for seriously biased predictions or misleading insights from the models. Our plenary paper, by William Kendall (Kendall, 2004, gives an overview of the use of Multi–state Mark–Recapture (MSMR models to address two such violations. The first is the occurrence of unobservable states that can arise, for example, from temporary emigration or by incomplete sampling coverage of a target population. Such states can also occur for life history reasons, such

STRATEGIC DECISION MAKING, ENTREPRENEURIAL ORIENTATION AND PERFORMANCE: AN ORGANIZATIONAL LIFE CYCLE APPROACH

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Héctor Montiel Campos

2015-06-01

Full Text Available EntrepreneurialOrientation (EO and Strategic Decision Making (SDM have been studied in awide variety of settings. However, there is not enough research available thatcombines both topics and studies the ways in which entrepreneurs make strategicdecisions in early stages of organizational life cycle. The purpose of thisresearch was therefore to examine the effects of the factors associated withthe decision maker influencing EO and performance for two categories of firms.The results were achieved by using empirical data from two independent samplesof firms in different stages of organizational life cycle: start-up stage (n=133 and growth stage (n=173. The results show that SDM andcontrol variables have different effects in the two samples; however, for bothsamples there is significant relation between EO and performance. The paperconcludes with a discussion about the results and suggestions for futureresearch.

Habits of the heart: life history and the developmental neuroendocrinology of emotion.

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Worthman, Carol M

2009-01-01

The centrality of emotion in cognition and social intelligence as well as its impact on health has intensified investigation into the causes and consequences of individual variation in emotion regulation. Central processing of experience directly informs regulation of endocrine axes, essentially forming a neuro-endocrine continuum integrating information intake, processing, and physiological and behavioral response. Two major elements of life history-resource allocation and niche partitioning-are served by linking cognitive-affective with physiologic and behavioral processes. Scarce cognitive resources (attention, memory, and time) are allocated under guidance from affective co-processing. Affective-cognitive processing, in turn, regulates physiologic activity through neuro-endocrine outflow and thereby orchestrates energetic resource allocation and trade-offs, both acutely and through time. Reciprocally, peripheral activity (e.g., immunologic, metabolic, or energetic markers) influences affective-cognitive processing. By guiding attention, memory, and behavior, affective-cognitive processing also informs individual stances toward, patterns of activity in, and relationships with the world. As such, it mediates processes of niche partitioning that adaptively exploit social and material resources. Developmental behavioral neurobiology has identified multiple factors that influence the ontogeny of emotion regulation to form affective and behavioral styles. Evidence is reviewed documenting roles for genetic, epigenetic, and experiential factors in the development of emotion regulation, social cognition, and behavior with important implications for understanding mechanisms that underlie life history construction and the sources of differential health. Overall, this dynamic arena for research promises to link the biological bases of life history theory with the psychobehavioral phenomena that figure so centrally in quotidian experience and adaptation, particularly, for

Effects of social information on life history and mating tactics of males in the orb-web spider Argiope bruennichi.

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Cory, Anna-Lena; Schneider, Jutta M

2018-01-01

Informed mating decisions are often based on social cues providing information about prospective mating opportunities. Social information early in life can trigger developmental modifications and influence later mating decisions. A high adaptive value of such adjustments is particularly obvious in systems where potential mating rates are extremely limited and have to be carried out in a short time window. Males of the sexually cannibalistic spider Argiope bruennichi can achieve maximally two copulations which they can use for one (monogyny) or two females (bigyny). The choice between these male mating tactics should rely on female availability that males might assess through volatile sex pheromones emitted by virgin females. We predict that in response to those female cues, males of A. bruennichi should mature earlier and at a smaller body size and favor a bigynous mating tactic in comparison with controls. We sampled spiders from two areas close to the Southern and Northern species range to account for differences in mate quality and seasonality. In a fully factorial design, half of the subadult males from both areas obtained silk cues of females, while the other half remained without female exposure. Adult males were subjected to no-choice mating tests and could either monopolize the female or leave her (bigyny). We found that Southern males matured later and at a larger size than Northern males. Regardless of their origin, males also shortened the subadult stage in response to female cues, which, however, had no effects on male body mass. Contrary to our prediction, the frequencies of mating tactics were unaffected by the treatment. We conclude that while social cues during late development elicit adaptive life history adjustments, they are less important for the adjustment of mating decisions. We suggest that male tactics mostly rely on local information at the time of mate search.

Fast life history traits promote invasion success in amphibians and reptiles.

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Allen, William L; Street, Sally E; Capellini, Isabella

2017-02-01

Competing theoretical models make different predictions on which life history strategies facilitate growth of small populations. While 'fast' strategies allow for rapid increase in population size and limit vulnerability to stochastic events, 'slow' strategies and bet-hedging may reduce variance in vital rates in response to stochasticity. We test these predictions using biological invasions since founder alien populations start small, compiling the largest dataset yet of global herpetological introductions and life history traits. Using state-of-the-art phylogenetic comparative methods, we show that successful invaders have fast traits, such as large and frequent clutches, at both establishment and spread stages. These results, together with recent findings in mammals and plants, support 'fast advantage' models and the importance of high potential population growth rate. Conversely, successful alien birds are bet-hedgers. We propose that transient population dynamics and differences in longevity and behavioural flexibility can help reconcile apparently contrasting results across terrestrial vertebrate classes. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

The secret life of decisions how unconscious bias subverts your judgement

CERN Document Server

Thuraisingham, Meena

2013-01-01

The Secret Life of Decisions exposes the unchallenged myths and distortions that impact our reasoning ability, raising our awareness of the many traps we can fall into. The authors have drawn from decades of work with leaders showing that even the most talented leaders and teams can end up making sub-optimal decisions. This is rarely because they had poor critical thinking faculties but rather because they did not pay enough attention to the often invisible traps hardwired into our thinking processes, letting through only information that conforms with our current beliefs, mental models and ex

Like cognitive function, decision making across the life span shows profound age-related changes.

Science.gov (United States)

Tymula, Agnieszka; Rosenberg Belmaker, Lior A; Ruderman, Lital; Glimcher, Paul W; Levy, Ifat

2013-10-15

It has long been known that human cognitive function improves through young adulthood and then declines across the later life span. Here we examined how decision-making function changes across the life span by measuring risk and ambiguity attitudes in the gain and loss domains, as well as choice consistency, in an urban cohort ranging in age from 12 to 90 y. We identified several important age-related patterns in decision making under uncertainty: First, we found that healthy elders between the ages of 65 and 90 were strikingly inconsistent in their choices compared with younger subjects. Just as elders show profound declines in cognitive function, they also show profound declines in choice rationality compared with their younger peers. Second, we found that the widely documented phenomenon of ambiguity aversion is specific to the gain domain and does not occur in the loss domain, except for a slight effect in older adults. Finally, extending an earlier report by our group, we found that risk attitudes across the life span show an inverted U-shaped function; both elders and adolescents are more risk-averse than their midlife counterparts. Taken together, these characterizations of decision-making function across the life span in this urban cohort strengthen the conclusions of previous reports suggesting a profound impact of aging on cognitive function in this domain.

Defoliation and bark harvesting affect life-history traits of a tropical tree

DEFF Research Database (Denmark)

Gaoue, Orou; Horvitz, Carol; Ticktin, Tamara

2013-01-01

Selectively harvesting whole individuals in managed populations (e.g. fisheries, hunting) has substantial effects on life expectancy and age at maturity. Although demographic rates of trees are impacted by recurrent harvest of plant organs (e.g. fruit, leaf, bark) known as non-timber forest...... of life expectancy to perturbation of vital rates to the elasticities of population growth rate, emphasizing how the two kinds of elasticity address distinct biological issues and management goals. Life expectancy was shorter and reproduction delayed in the dry than in the moist region, indicating a cost...... of drought to life-history traits. Harvesting at constant rates only affects (increased) life expectancy in the moist region and (reduced) age at first reproduction in the dry region. Models in which harvest intensity varies stochastically over time show results similar to those with constant harvesting rate...

The Societal Impact of Extraterrestrial Life: The Relevance of History and the Social Sciences

Science.gov (United States)

Dick, Steven J.

This chapter reviews past studies on the societal impact of extraterrestrial life and offers four related ways in which history is relevant to the subject: the history of impact thus far, analogical reasoning, impact studies in other areas of science and technology, and studies on the nature of discovery and exploration. We focus particularly on the promise and peril of analogical arguments, since they are by necessity widespread in the field. This chapter also summarizes the relevance of the social sciences, particularly anthropology and sociology, and concludes by taking a closer look at the possible impact of the discovery of extraterrestrial life on theology and philosophy. In undertaking this study we emphasize three bedrock principles: (1) we cannot predict the future; (2) society is not monolithic, implying many impacts depending on religion, culture and worldview; (3) the impact of any discovery of extraterrestrial life is scenario-dependent.

High Decision Latitude at Work Combined with Traumatic Life Events in Private Life is Associated with Reduced Sleep Quality: Results from the GAZEL Study

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Nadya Dich

2018-04-01

Full Text Available Psychosocial stress, both at work and at home, plays a role in sleep disturbances. Theoretical models of stress underscore the cumulative effect of stress from different domains in affecting health and well-being. However, previous research has not considered how work stress and stress in private life might interact to affect sleep. The study investigated potential synergistic effects of work stress and traumatic events in private life on sleep quality. Participants ('N' = 6552, average baseline age = 52 were a subset of the French GAZEL cohort who were working in 1999. Work stress was operationalized as high job demands and low decision latitude. These working conditions were self-reported in 1999 (study baseline. Traumatic events in the past 12 months were reported in 2000. Sleep quality was assessed in 2000 as disturbed sleep in the past 12 months, and current sleep problems was indexed by the sleep subscale of the Nottingham Health Profile questionnaire. The results showed that recent events interacted with decision latitude, but not job demands, in predicting sleep quality. However, contrary to our expectations, it was 'high' and not low decision latitude at work that amplified the negative association between stressful events and sleep quality. Adjusted for baseline health, individuals with highest numbers of events and highest levels of decision latitude were at highest risk for impaired sleep. These results challenge the idea that high decision latitude always serves as a protective factor, and underscore the necessity for considering a broader life context when studying stress in a particular domain of life.

Energy regulation in context: Free-living female arctic ground squirrels modulate the relationship between thyroid hormones and activity among life history stages.

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Wilsterman, Kathryn; Buck, C Loren; Barnes, Brian M; Williams, Cory T

2015-09-01

Thyroid hormones (THs), key regulators of lipid and carbohydrate metabolism, are likely modulators of energy allocation within and among animal life history stages. Despite their role in modulating metabolism, few studies have investigated whether THs vary among life history stages in free-living animals or if they exhibit stage-specific relationships to total energy expenditure and activity levels. We measured plasma total triiodothyronine (tT3) and thyroxine (tT4) at four, discrete life history stages of female arctic ground squirrels from two different populations in northern Alaska to test whether plasma THs correlate with life history stage-specific changes in metabolic rate and energy demand. We also tested whether THs explained individual variation in aboveground activity levels within life history stages. T3 peaked during lactation and was lowest during pre-hibernation fattening, consistent with known changes in basal metabolism and core body temperature. In contrast, T4 was elevated shortly after terminating hibernation but remained low and stable across other life-history stages in the active season. THs were consistently higher in the population that spent more time above-ground but the relationship between THs and activity varied among life history stages. T3 was positively correlated with activity only during lactation (r(2)=0.50) whereas T4 was positively correlated with activity immediately following lactation (r(2)=0.48) and during fattening (r(2)=0.53). Our results support the hypothesis that THs are an important modulator of basal metabolism but also suggest that the relationship between THs and activity varies among life history stages. Copyright © 2015 Elsevier Inc. All rights reserved.

Research on Group Decision-Making Mechanism of Internet Emergency Management

Science.gov (United States)

Xie, Kefan; Chen, Gang; Qian, Wu; Shi, Zhao

With the development of information technology, internet has become a popular term and internet emergency has an intensive influence on people's life. This article offers a short history of internet emergency management. It discusses the definition, characteristics, and factor of internet emergency management. A group decision-making mechanism of internet emergency is presented based on the discussion. The authors establish a so-called Rough Set Scenario Flow Graphs (RSSFG) of group decision-making mechanism of internet emergency management and make an empirical analysis based on the RSSFG approach. The experimental results confirm that this approach is effective in internet emergency decision-making.

Life and Death Decision Making, by Baruch A. Brody.

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Veatch, Robert M

1989-04-01

Veatch considers the pluralistic casuistry theory advocated by Baruch Brody in his 1988 book, Life and Death Decision Making, to be an important contribution to the secular medical ethics literature. The casuistic and pluralistic elements of Brody's new model are described as intriguing but controversial because Brody both excludes several ethical appeals (i.e., classical Hippocratic ethics, virtue theory) and/or limits other questionable appeals (i.e., consequences for families and others in society, the virtue of integrity) without accounting for these decisions. Veatch also questions Brody's use of intuitional judgment to determine what ought to be done after examination of various appeals and their significance because Brody's approach raises serious problems about how various appeals are counted. Veatch does affirm the rich assessment of medical ethical problems made possible by Brody's pluralistic approach but notes the difficulties it raises.

Education, Information, and Smoking Decisions : Evidence from Smoking Histories in the United States, 1940-2000

OpenAIRE

de Walque, Damien

2010-01-01

This paper tests the hypothesis that education improves health and increases life expectancy. The analysis of smoking histories shows that after 1950, when information about the dangers of tobacco started to diffuse, the prevalence of smoking declined earlier and most dramatically for college graduates. I construct panels based on smoking histories in an attempt to isolate the causal effect of smoking from the influence of time-invariant unobservable characteristics. The results suggest that,...

Social environment affects the life history tactic of a phoretic mite

DEFF Research Database (Denmark)

Nehring, Volker; Müller, Josef K

2009-01-01

Phoretic animals use their hosts for travelling to habitat patches suitable for reproduction. Some species, such as the mite Poecilochirus carabi, are phoretic as juveniles and cannot leave their habitat once they reach adulthood. Previous work has shown that mites exercise choice over the habitat...... influence of the social environment on a phoretic's habitat choice and life history....

Impact of landfill liner time-temperature history on the service life of HDPE geomembranes.

Science.gov (United States)

Rowe, R Kerry; Islam, M Z

2009-10-01

The observed temperatures in different landfills are used to establish a number of idealized time-temperature histories for geomembrane liners in municipal solid waste (MSW) landfills. These are then used for estimating the service life of different HDPE geomembranes. The predicted antioxidant depletion times (Stage I) are between 7 and 750 years with the large variation depending on the specific HDPE geomembrane product, exposure conditions, and most importantly, the magnitude and duration of the peak liner temperature. The higher end of the range corresponds to data from geomembranes aged in simulated landfill liner tests and a maximum liner temperature of 37 degrees C. The lower end of the range corresponds to a testing condition where geomembranes were immersed in a synthetic leachate and a maximum liner temperature of 60 degrees C. The total service life of the geomembranes was estimated to be between 20 and 3300 years depending on the time-temperature history examined. The range illustrates the important role that time-temperature history could play in terms of geomembrane service life. The need for long-term monitoring of landfill liner temperature and for geomembrane ageing studies that will provide improved data for assessing the likely long-term performance of geomembranes in MSW landfills are highlighted.

Octopus life history relative to age, in a multi-geared developmental fishery

NARCIS (Netherlands)

Leporati, S.C.; Hart, A.M.; Larsen, R.; Franken, Linda E; De Graaf, M.

2015-01-01

The ability to obtain broad-scale age information for an exploited octopus population enables the identification of essential life history information, such as age at maturity, recruitment pulses and seasonal effects on growth. This study uses stylet weight (reduced internal shell) as a proxy to age

Physical activity history and end-of-life hospital and long-term care

DEFF Research Database (Denmark)

von Bonsdorff, Mikaela B; Rantanen, Taina; Leinonen, Raija

2009-01-01

persons aged 66-98 years at death, who, on average 5.8 years prior to death, had participated in an interview about their current and earlier physical activity. Data on the use of care in the last year of life are register-based data and complete. RESULTS: Men needed on average 96 days (SD 7.0) and women.......06-2.43), than for those who had been consistently active from midlife onward, whereas use of hospital care did not correlate with physical activity history. CONCLUSION: People who had been physically active since midlife needed less end-of-life inpatient care but patterns differed between men and women....... had been consistently physically active, whereas use of long-term care did not correlate with physical activity history. Among women, the risk for long-term care was higher for those who had been sedentary (IRR 2.03, 95% CI 1.28-3.21) or only occasionally physically active (IRR 1.60, 95% CI 1...

Buddhist ethics and end-of-life care decisions.

Science.gov (United States)

McCormick, Andrew J

2013-01-01

Buddhism has grown in the United States in the past 50 years. Immigrants come following long traditions. American converts are more eclectic. The first Buddhist precept prohibiting harm to living things, the virtue of compassion, and the goal of a peaceful death provide guidance for ethical decision making regarding organ donation, withholding and withdrawing life-sustaining treatment, voluntary cessation of eating, physician aid in dying, and euthanasia. Concepts and views from three Buddhist traditions and views of master practitioners are presented. Case examples illustrate some of the differences within Buddhism. Suggestions for social workers are provided.

Negotiating end-of-life decision making: a comparison of Japanese and U.S. residents' approaches.

Science.gov (United States)

Gabbay, Baback B; Matsumura, Shinji; Etzioni, Shiri; Asch, Steven M; Rosenfeld, Kenneth E; Shiojiri, Toshiaki; Balingit, Peter P; Lorenz, Karl A

2005-07-01

To compare Japanese and U.S. resident physicians' attitudes, clinical experiences, and emotional responses regarding making disclosures to patients facing incurable illnesses. From September 2003 to June 2004, the authors used a ten-item self-administered anonymous questionnaire in a cross-sectional survey of 103 internal medicine residents at two U.S. sites in Los Angeles, California, and 244 general medical practice residents at five Japanese sites in Central Honshu, Kyushu, Okinawa, Japan. The Japanese residents were more likely to favor including the family in disclosing diagnosis (95% versus 45%, pguilt about these behaviors. The residents' approaches to end-of-life decision making reflect known cultural preferences related to the role of patients and their families. Although Japanese trainees were more likely to endorse the role of the family, they expressed greater uncertainty about their approach. Difficulty and uncertainty in end-of-life decision making were common among both the Japanese and U.S. residents. Both groups would benefit from ethical training to negotiate diverse, changing norms regarding end-of-life decision making.

Counterfactuals and history: Contingency and convergence in histories of science and life.

Science.gov (United States)

Hesketh, Ian

2016-08-01

This article examines a series of recent histories of science that have attempted to consider how science may have developed in slightly altered historical realities. These works have, moreover, been influenced by debates in evolutionary science about the opposing forces of contingency and convergence in regard to Stephen Jay Gould's notion of "replaying life's tape." The article argues that while the historians under analysis seem to embrace contingency in order to present their counterfactual narratives, for the sake of historical plausibility they are forced to accept a fairly weak role for contingency in shaping the development of science. It is therefore argued that Simon Conway Morris's theory of evolutionary convergence comes closer to describing the restrained counterfactual worlds imagined by these historians of science than does contingency. Copyright © 2015 Elsevier Ltd. All rights reserved.

Endogenous ROS levels in C. elegans under exogenous stress support revision of oxidative stress theory of life-history tradeoffs.

Science.gov (United States)

Smith, Samson W; Latta, Leigh C; Denver, Dee R; Estes, Suzanne

2014-07-24

The oxidative stress theory of life-history tradeoffs states that oxidative stress caused by damaging free radicals directly underpins tradeoffs between reproduction and longevity by altering the allocation of energetic resources between these tasks. We test this theory by characterizing the effects of exogenous oxidative insult and its interaction with thermal stress and diet quality on a suite of life-history traits and correlations in Caenorhabditis elegans nematodes. We also quantify demographic aging rates and endogenous reactive oxygen species (ROS) levels in live animals. Our findings indicate a tradeoff between investment in reproduction and antioxidant defense (somatic maintenance) consistent with theoretical predictions, but correlations between standard life-history traits yield little evidence that oxidative stress generates strict tradeoffs. Increasing oxidative insult, however, shows a strong tendency to uncouple positive phenotypic correlations and, in particular, to reduce the correlation between reproduction and lifespan. We also found that mild oxidative insult results in lower levels of endogenous ROS accompanied by hormetic changes in lifespan, demographic aging, and reproduction that disappear in combined-stress treatments--consistent with the oxidative stress theory of aging. Our findings demonstrate that oxidative stress is a direct contributor to life-history trait variation and that traditional tradeoffs are not necessary to invoke oxidative stress as a mediator of relationships between life-history traits, supporting previous calls for revisions to theory.

Understanding life together: A brief history of collaboration in biology

Science.gov (United States)

Vermeulen, Niki; Parker, John N.; Penders, Bart

2013-01-01

The history of science shows a shift from single-investigator ‘little science’ to increasingly large, expensive, multinational, interdisciplinary and interdependent ‘big science’. In physics and allied fields this shift has been well documented, but the rise of collaboration in the life sciences and its effect on scientific work and knowledge has received little attention. Research in biology exhibits different historical trajectories and organisation of collaboration in field and laboratory – differences still visible in contemporary collaborations such as the Census of Marine Life and the Human Genome Project. We employ these case studies as strategic exemplars, supplemented with existing research on collaboration in biology, to expose the different motives, organisational forms and social dynamics underpinning contemporary large-scale collaborations in biology and their relations to historical patterns of collaboration in the life sciences. We find the interaction between research subject, research approach as well as research organisation influencing collaboration patterns and the work of scientists. PMID:23578694

The impact of regional culture on intensive care end of life decision making: an Israeli perspective from the ETHICUS study.

Science.gov (United States)

Ganz, F D; Benbenishty, J; Hersch, M; Fischer, A; Gurman, G; Sprung, C L

2006-04-01

Decisions of patients, families, and health care providers about medical care at the end of life depend on many factors, including the societal culture. A pan-European study was conducted to determine the frequency and types of end of life practices in European intensive care units (ICUs), including those in Israel. Several results of the Israeli subsample were different to those of the overall sample. The objective of this article was to explore these differences and provide a possible explanation based on the impact of culture on end of life decision making. All adult patients admitted consecutively to three Israeli ICUs (n = 2778) who died or underwent any limitation of life saving interventions between 1 January 1999 and 30 June 2000 were studied prospectively (n = 363). These patients were compared with a similar sample taken from the larger study (ethics in European intensive care units: ETHICUS) carried out in 37 European ICUs. Patients were followed until discharge, death, or 2 months from the decision to limit therapy. End of life decisions were prospectively organised into one of five mutually exclusive categories: cardiopulmonary resuscitation (CPR), brain death, withholding treatment, withdrawing treatment, and active shortening of the dying process (SDP). The data also included patient characteristics (gender, age, ICU admission diagnosis, chronic disorders, date of hospital admission, date and time of decision to limit therapy, date of hospital discharge, date and time of death in hospital), specific therapies limited, and the method of SDP. The majority of patients (n = 252, 69%) had treatment withheld, none underwent SDP, 62 received CPR (17%), 31 had brain death (9%), and 18 underwent withdrawal of treatment (5%). The primary reason given for limiting treatment was that the patient was unresponsive to therapy (n = 187). End of life discussions were held with 132 families (36%), the vast majority of which revolved around withholding treatment (91

Decision-Making of Patients With Implantable Cardioverter-Defibrillators at End of Life: Family Members' Experiences.

Science.gov (United States)

Lee, Mei Ching; Sulmasy, Daniel P; Gallo, Joseph; Kub, Joan; Hughes, Mark T; Russell, Stuart; Kellogg, Anela; Owens, Sharon G; Terry, Peter; Nolan, Marie T

2017-07-01

Many patients with advanced heart failure (HF) experience the life-extending benefits of implantable cardioverter-defibrillators (ICD), but at the end stage of HF, patients may experience shocks with increasing frequency and change the plan for end-of-life (EOL) care including the deactivation of the ICD. This report describes family members' experiences of patients with ICD making decisions at EOL. Understanding the decision-making of patients with ICD at EOL can promote informed decision-making and improve the quality of EOL care. This pilot study used a mixed methods approach to test the effects of a nurse-guided discussion in decision-making about ICD deactivation (turning off the defibrillation function) at the EOL. Interviews were conducted, audiotaped, and transcribed in 2012 to 2013 with 6 family members of patients with advanced HF and ICDs. Three researchers coded the data and identified themes in 2014. Three main themes described family members' experiences related to patients having HF with ICDs making health-care decision at EOL: decision-making preferences, patients' perception on ICD deactivation, and communication methods. Health-care providers need to have knowledge of patients' decision-making preferences. Preferences for decision-making include the allowing of appropriate people to involve and encourages direct conversation with family members even when advance directives is completed. Information of ICD function and the option of deactivation need to be clearly delivered to patients and family members. Education and guidelines will facilitate the communication of the preferences of EOL care.

Theorizing Learning in Life History - a psycho-societal approach

DEFF Research Database (Denmark)

Olesen, Henning Salling

2007-01-01

to the understanding of knowledge, based on examples from the author's research into professional learning (general practitioners). The pivotal role of language use and language socialisation is explained in brief, developing a psychodynamic complement to a language game concept of language use.......  Taking it's point of departure in some critical remarks to some of the most important recent theorizing of learning, this article presents an alternative framework for theorizing learning as a subjective process in a social and societal context, based in life history research. Key concepts...

IMPACT OF HATCH-DATE ON EARLY LIFE GROWTH AND SURVIVAL OF MUELLER’S PEARLSIDE (MAUROLICUS MUELLERI) LARVAE, AND LIFE-HISTORY CONSEQUENCES

KAUST Repository

Folkvord, Arild; Gundersen, Geir; Albretsen, Jon; Asplin, Lars L; Kaartvedt, Stein; Giske, Jarl

2015-01-01

and variable survival due to short term fluctuations in environmental conditions indicate that multiple batch spawning is an adequately evolved life history strategy for marine planktivorous fish such as M. muelleri.

Voices of African American, Caucasian, and Hispanic surrogates on the burdens of end-of-life decision making.

Science.gov (United States)

Braun, Ursula K; Beyth, Rebecca J; Ford, Marvella E; McCullough, Laurence B

2008-03-01

End-of-life decisions are frequently made by patients' surrogates. Race and ethnicity may affect such decision making. Few studies have described how different racial/ethnic groups experience end-of-life surrogate decision making. To describe the self-reported experience the self-reported experience of African-American, Caucasian, and Hispanic surrogate decision makers of seriously ill patients and to examine the relationship of race, ethnicity, and culture to that experience. Purposive sample to include racial/ethnic minorities in a qualitative study using focus group interviews. The participants of the study were 44 experienced, mostly female, surrogate decision makers for older veterans. Transcripts were qualitatively analyzed to identify major themes, with particular attention to themes that might be unique to each of the three groups. The experience of burden of end-of-life decision making was similar in all three groups. This burden in its medical, personal, and familial dimensions is compounded by uncertainty about prognosis and the patient's preferences. Racial/ethnic variations of responses to this burden concerned the physician-family relationship, religion and faith, and past experiences with race/ethnicity concordant versus non-concordant physicians. Regardless of race/ethnicity, surrogates for seriously ill patients appeared to experience increased significant, multidimensional burdens of decision making under conditions of uncertainty about a patient's preferences. This aspect of the burden of surrogate decision making may not be fully appreciated by physicians. Physicians should identify and be especially attentive to strategies used by surrogates, which may vary by race/ethnicity, to reduce the uncertainty about a patient's preferences and thus the burden of surrogate decision making to assist them in this difficult process.

A genetics-based approach confirms immune associations with life history across multiple populations of an aquatic vertebrate (Gasterosteus aculeatus).

Science.gov (United States)

Whiting, James R; Magalhaes, Isabel S; Singkam, Abdul R; Robertson, Shaun; D'Agostino, Daniele; Bradley, Janette E; MacColl, Andrew D C

2018-06-20

Understanding how wild immune variation covaries with other traits can reveal how costs and trade-offs shape immune evolution in the wild. Divergent life history strategies may increase or alleviate immune costs, helping shape immune variation in a consistent, testable way. Contrasting hypotheses suggest that shorter life histories may alleviate costs by offsetting them against increased mortality; or increase the effect of costs if immune responses are traded off against development or reproduction. We investigated the evolutionary relationship between life history and immune responses within an island radiation of three-spined stickleback, with discrete populations of varying life histories and parasitism. We sampled two short-lived, two long-lived and an anadromous population using qPCR to quantify current immune profile and RAD-seq data to study the distribution of immune variants within our assay genes and across the genome. Short-lived populations exhibited significantly increased expression of all assay genes, which was accompanied by a strong association with population-level variation in local alleles and divergence in a gene that may be involved in complement pathways. In addition, divergence around the eda gene in anadromous fish is likely associated with increased inflammation. A wider analysis of 15 populations across the island revealed that immune genes across the genome show evidence of having diverged alongside life history strategies. Parasitism and reproductive investment were also important sources of variation for expression, highlighting the caution required when assaying immune responses in the wild. These results provide strong, gene-based support for current hypotheses linking life history and immune variation across multiple populations of a vertebrate model. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Real-life decision making in college students. II: Do individual differences show reliable effects?