Experimental immune activation using a mild antigen decreases reproductive success in free-living female Dark-eyed Juncos (Junco hyemalis)

2017 ◽  
Vol 95 (4) ◽  
pp. 263-269 ◽  
Author(s):  
J.L. Graham ◽  
R.P. Mady ◽  
T.J. Greives
Keyword(s):  
Reproductive Success ◽  
Antibody Production ◽  
Immune Activation ◽  
Future Research ◽  
Life History Stage ◽  
Junco Hyemalis ◽  
Trade Off ◽  
Growth And Survival ◽  
Nestling Feeding ◽  
Favorable Conditions

Seasonal animals time breeding so that offspring rearing coincides with favorable conditions. Offspring rearing is energetically demanding; therefore, additional energetic challenges during this life-history stage may allocate energy away from offspring care, decreasing reproductive success. Activation of the immune system may be one such energetic challenge, and may have a disproportionately higher impact on reproductive success earlier in the breeding season when resources are less abundant and thermoregulatory demands are greater. We monitored nestling growth and survival in incubating female Dark-eyed Juncos (Junco hyemalis (L., 1758)) injected with a mild antigen to stimulate antibody production and induce an energetic challenge. We found nests of treated females were more likely than controls to fail prior to 6 days post hatch, coinciding with timing of peak antibody production. No effect of season was detected. Offspring mass did not differ between treatments prior to failure, suggesting that failure was potentially due to differences in behaviour other than nestling feeding. Our findings indicate a trade-off between immunity and nest survival that is not affected by time of season. Based on the results of our study, we suggest that future research be directed toward how immune activation influences behaviours, including nest guarding and predator aggression, and mediates this trade-off.

120 The Experience of Housing Need Amongst Families Caring for Children with Medical Complexity: A Qualitative Study

2021 ◽  
Vol 26 (Supplement_1) ◽  
pp. e85-e88
Author(s):  
Clara Moore ◽  
Kara Grace Hounsell ◽  
Arielle Zahavi ◽  
Danielle Arje ◽  
Natalie Weiser ◽  
...  
Keyword(s):  
Qualitative Study ◽  
Future Research ◽  
Complex Care ◽  
Housing Situation ◽  
Children With Medical Complexity ◽  
Trade Off ◽  
Housing Preferences ◽  
Medical Needs ◽  
Medical Complexity ◽  
The Impact

Abstract Primary Subject area Complex Care Background Caregivers of children with medical complexity (CMC) face many financial, social and emotional stressors related to their child’s medical condition(s). Previous research has demonstrated that financial stress among this population can have an impact on their housing situation. Families of CMC may face other unique housing challenges such as disability accommodations in the home and housing space and layout. Objectives The primary aim of this study was to explore families’ perspectives and experiences of housing need, and its relationship to their child’s health status as it pertains to CMC. Design/Methods We conducted a qualitative study using semi-structured interviews to identify themes surrounding families of CMC’s experiences of housing need. Parents of CMC were recruited through purposive sampling from the Complex Care Program at a tertiary pediatric health sciences centre. Recruitment ceased when thematic saturation was reached, as determined by consensus of the research team. Interviews were recorded, transcribed verbatim, coded, and analyzed using thematic analysis. Results Twenty parents completed the interview, of whom 89% were mothers and 42% identified a non-English language as their first language. Two major themes and five subthemes (in parentheses) were identified: 1) the impact of health on housing (housing preferences, housing possibilities, housing outcome as a trade-off) and 2) the impact of housing on health (health of the caregiver, health of the child). Some parents reported that their child’s medical needs resulted in specific preferences regarding the location and layout of their home. Parents also indicated that their caregiving role often affected their income and home ownership status, which in turn, affected their housing possibilities. Thus, the housing situation (location and layout of the home) was often the result of a trade-off between the parent’s housing preferences and possibilities. Conclusion Housing is a recognized social determinant of health. We found that among CMC, health also appears to be a significant determinant of housing as families reported that the health of their child impacted their housing preferences and the options available to them (possibilities). To support the health of CMC and their families, policies targeting improved access to subsidized housing, improved sources of funding and regulations allowing families who rent to make accessibility changes are vital. Future research should investigate the impact of household income on housing need and identify interventions to support appropriate housing for CMC.

Evidence of long and discontinuous juvenile periods in Trillium catesbaei under contrasting levels of herbivory

Botany ◽  
2014 ◽  
Vol 92 (1) ◽  
pp. 77-81 ◽  
Author(s):  
Christopher R. Webster ◽  
Michael A. Jenkins
Keyword(s):  
Life History ◽  
Reproductive Success ◽  
Age Structure ◽  
Morphological Characteristics ◽  
Population Viability ◽  
Plant Age ◽  
Life History Stage ◽  
Structure And Morphology ◽  
Single Leaf ◽  
Poor Indicator

We investigated the influence of chronic herbivory by white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) on the age structure and morphology of Trillium catesbaei Elliott. At sites with contrasting histories of deer abundance (Cades Cove, high; Whiteoak Sink, low), we measured morphological characteristics and determined minimum plant age for 60 plants (30 per site) in the single-leaf life-history stage. We chose this stage because its presence is considered an indication of successful reproduction by the previous generation, but its value could be inflated if plants regress or remain in this stage for extended periods. Our results suggest that T. catesbaei may spend upwards of a decade in this stage. Cades Cove single leaves were significantly older (p = 0.011) than those at Whiteoak Sink. Rhizome recession (decay of the oldest portion) was more common at Cades Cove, suggesting greater regression to this stage from three-leaf stages. Although minimum plant age was significantly associated with vegetative attributes (p < 0.002) at Whiteoak Sink, these attributes were decoupled at Cades Cove (p ≥ 0.642). Collectively, our results suggest that chronic herbivory may lead to a long and regressive residency period in the single-leaf stage. Consequently, in Trillium populations heavily impacted by deer, the number of single-leaf plants may be a poor indicator of reproductive success and population viability.

scholarly journals Exploring Early Detection of Frailty Syndrome in Older Adults: Evaluation of Oxi-Immune Markers, Clinical Parameters and Modifiable Risk Factors

Antioxidants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1975
Author(s):  
Armanda Teixeira-Gomes ◽  
Blanca Laffon ◽  
Vanessa Valdiglesias ◽  
Johanna M. Gostner ◽  
Thomas Felder ◽  
...  
Keyword(s):  
Older Adults ◽  
Immune Activation ◽  
Future Research ◽  
Clinical Parameters ◽  
Frailty Syndrome ◽  
Immune Markers ◽  
Frailty Phenotype ◽  
Age Related ◽  
Inflammatory Molecules ◽  
The Relationship

Ageing is accompanied with a decline in several physiological systems. Frailty is an age-related syndrome correlated to the loss of homeostasis and increased vulnerability to stressors, which is associated with increase in the risk of disability, comorbidity, hospitalisation, and death in older adults. The aim of this study was to understand the relationship between frailty syndrome, immune activation, and oxidative stress. Serum concentrations of vitamins A and E were also evaluated, as well as inflammatory biomarkers (CRP and IL-6) and oxidative DNA levels. A group of Portuguese older adults (≥65 years old) was engaged in this study and classified according to Fried’s frailty phenotype. Significant increases in the inflammatory mediators (CRP and IL-6), neopterin levels, kynurenine to tryptophan ratio (Kyn/Trp), and phenylalanine to tyrosine ratio (Phe/Tyr), and significant decreases in Trp and Tyr concentrations were observed in the presence of frailty. IL-6, neopterin, and Kyn/Trp showed potential as predictable biomarkers of frailty syndrome. Several clinical parameters such as nutrition, dependency scales, and polypharmacy were related to frailty and, consequently, may influence the associations observed. Results obtained show a progressive immune activation and production of pro-inflammatory molecules in the presence of frailty, agreeing with the inflammageing model. Future research should include different dimensions of frailty, including psychological, social, biological, and environmental factors.

Literature review on effect of microfinance institutions on poverty in South Asian countries and their sustainability

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Prashant Kumar Gupta ◽  
Seema Sharma
Keyword(s):  
Literature Review ◽  
South Asian ◽  
Systematic Literature Review ◽  
Future Research ◽  
Microfinance Institutions ◽  
Asian Countries ◽  
Exclusion Criteria ◽  
Trade Off ◽  
Content Type ◽  
Positive Effect

PurposeThe authors present a systematic literature review on microfinance institutions’ (MFIs) effect on poverty and how they can ensure their sustainability. The purpose of this article is to review the effect of MFIs on poverty in South Asian countries. The analysis and review of the selected corpus of literature also provide avenues for future research.Design/methodology/approachA total of 95 papers from 49 journals in 4 academic libraries and publishers were systematically studied and classified. The authors define the keywords and the inclusion/exclusion criteria for the identification of papers. The review includes an analysis of the selected papers that give insights about publications with respect to themes, number of themes covered in individual publications, nations, scope, methodology, number of methods used and publication trend.FindingsThe literature indicates the positive effect of microfinance on poverty but with a varying degree on various categories of poor. The relation between poverty and microfinance is, however, dependent on the nation under the scanner. While sustainability and outreach co-exist, their trade-off is still a matter of debate.Originality/valueThis is the first systematic literature review on MFIs’ effect on poverty in South Asian nations. Additionally, the authors discuss the literature on the trade-off between sustainability and outreach for MFIs.

Effort-Accuracy Trade-Off in Using Knowledge Management Systems

2010 ◽  
pp. 2226-2252
Author(s):  
Robin S. Poston ◽  
Cheri Speier
Keyword(s):  
Knowledge Management ◽  
Research Study ◽  
Management Systems ◽  
Future Research ◽  
Cognitive Resources ◽  
Knowledge Management Systems ◽  
Trade Off ◽  
Content Quality ◽  
Computer Mediated

To solve complicated problems, people often seek input from others. Knowledge management systems (KMSs) provide help in this activity by offering a computer-mediated approach to information sharing. However, if the KMS contains content that is obsolete or incomplete, those using the system may expend greater amounts of effort to detect what content is worthwhile or they risk relying on poor inputs, which may lead to less accurate solutions to their problems. As a result, most KMSs include rating schemes as part of the user interface designed to help those using the system identify high-quality content. Rating schemes depend on current users rating the quality of the existing content, guiding subsequent users in future content searches. If specific ratings are low in validity, then they may not reflect the true content quality (unintentionally or intentionally). This chapter provides a robust summary of the KMS literature and draws on the effort-accuracy trade-off framework to offer the results of a research study. The research study examines how rating validity influences how KMS users employ their limited cognitive resources to search and evaluate KMS content, with the goal of finding and using the highest-quality content. Through an experimental design, the study described herein manipulates rating validity and content quality in a replicated KMS setting and examines how users trade off search and evaluation effort. The results of the study demonstrate that rating validity differentially influences how KMS search and evaluation effort relates to decision accuracy. The chapter concludes with a discussion of the study findings and ideas for future research.

Games Embedded in Life

2020 ◽  
pp. 203-230
Author(s):  
John M. McNamara ◽  
Olof Leimar
Keyword(s):  
Reproductive Success ◽  
Dynamic Games ◽  
Traditional Approach ◽  
Holistic Approach ◽  
Current Situation ◽  
Lifetime Reproductive Success ◽  
Trade Off ◽  
State Dependent ◽  
Mean Lifetime ◽  
Payoff Structure

Many games focus on a part of the life of an organism. The payoff structure of the game then represents how the game affects fitness proxies such as mean lifetime reproductive success, which are concerned with the whole of the life of the organism. However, the traditional approach of specifying payoffs in advance of the analysis of the game can lead to inconsistencies because the rest of the life of an individual is not fixed but depends on what happens in the game. This chapter concerns this issue, identifying situations in which a more holistic approach is needed. A series of models illustrates links between the current situation and a lifetime perspective. When each of two parents must decide whether to care for their common young or desert, the payoff for desertion depends on the solution of the game and cannot be specified in advance. A game in which two males contest for a female illustrates the approach that must be taken if this game can be repeated at a later time. A game in which individuals must possess territories in order to breed is developed that highlights various interdependencies and, by incorporating learning, advances the understanding of owner–intruder interactions. The interdependencies in state-dependent dynamic games are also illustrated with a model in which individuals must trade off the risks of starvation and predation in a situation in which the choice of the best foraging habitat depends on the number of other animals that use that habitat.

scholarly journals Early Infestation by Bot Flies (Philornis Seguyi) Decreases Chick Survival and Nesting Success in Chalk-Browed Mockingbirds (Mimus Saturninus)

The Auk ◽  
2007 ◽  
Vol 124 (3) ◽  
pp. 898-906 ◽  
Author(s):  
Fabián L. Rabuffetti ◽  
Juan C. Reboreda
Keyword(s):  
Reproductive Success ◽  
Nesting Success ◽  
Life History Strategies ◽  
Chick Survival ◽  
Southern Limit ◽  
Growth And Survival ◽  
Molothrus Bonariensis ◽  
Bot Fly ◽  
Time Of Breeding ◽  
Host Life

AbstractBot flies (Diptera: Muscidae: Philornis spp.) are a group of flies comprising mostly species with a Neotropical distribution. Their larvae parasitize several species of birds, living subcutaneously on altricial chicks. We investigated the effect of parasitism by bot flies (P. seguyi) on the reproductive success of Chalk-browed Mockingbirds (Mimus saturninus) in temperate grasslands near the southern limit of bot fly distributions. We analyzed seasonal variation of bot fly prevalence during three consecutive years and how the timing and intensity of bot fly infestation affected growth and survival of Chalk-browed Mockingbird nestlings. Bot fly prevalence was 58.3%, 30.7%, and 45.5% each year, and in all years, it increased with time of breeding. Most of the infested nests fledged no chicks. In these nests, chicks had a lower tarsus growth rate than in noninfested nests and died 3–4 days after parasitism. The average time from hatching of the first chick until infestation was 4.4 days. The age of the chicks at the time of infestation was associated positively with nesting success and negatively with intensity of parasitism. Bot fly parasitism also reduced the survival of Shiny Cowbird (Molothrus bonariensis) chicks present in Chalk-browed Mockingbird nests, but the presence of Shiny Cowbird chicks did not affect timing of infestation or fledging success of Chalk-browed Mockingbird chicks. Our results show that an intermediate prevalence of bot fly parasitism produces an important decrease in the reproductive success of Chalk-browed Mockingbirds and suggest that bot flies may play an important role as selective agents in the evolution of host life-history strategies.La Infestación Temprana con Larvas de Philornis seguyi Disminuye la Supervivencia de los Pichones y el Éxito de Nidificación de Mimus saturninus

A Simplified Bioenergetics Model of a Hammerhead Shark for Teaching Natural Selection

2019 ◽  
Vol 81 (2) ◽  
pp. 115-119
Author(s):  
Jay Y. S. Hodgson
Keyword(s):  
Natural Selection ◽  
Reproductive Success ◽  
Computer Simulations ◽  
Trade Off ◽  
Bioenergetics Model ◽  
Hammerhead Shark ◽  
Differential Reproductive Success ◽  
Evolutionary Consequences ◽  
Successful Predation

Students often have difficulty understanding the underpinning mechanisms of natural selection because they lack the means to directly test hypotheses within the classroom. Computer simulations are ideal platforms to allow students to manipulate variables and observe evolutionary outcomes; however, many available models solve the scenario for the users without revealing the evolutionarily significant calculations. I developed a simplified bioenergetics model of a hammerhead shark for teaching natural selection that allows the users to manipulate variables and see the impacts of modeling while solving for the evolutionary consequences. Students generate variation within the population by controlling cephalofoil widths and swimming speeds of an individual, which affect its ability to detect and capture prey at the expense of energy lost as drag from swimming. The trade-off between energy gained from successful predation and energy lost from metabolic expenditures dictates rates of reproduction. By manipulating a subset of factors that influence differential reproductive success, students gain an improved understanding of natural selection.

Marbled salamanders (Ambystoma opacum) choose low elevation nest sites when cover availability is controlled

2006 ◽  
Vol 27 (3) ◽  
pp. 359-364 ◽  
Author(s):  
David Scott ◽  
Dean Croshaw
Keyword(s):  
Reproductive Success ◽  
Reproductive Behavior ◽  
Site Selection ◽  
Nest Site ◽  
Local Environment ◽  
Breeding Site ◽  
Nest Site Selection ◽  
Growth And Survival ◽  
Nest Sites ◽  
Selective Forces

AbstractNest site selection is an important part of adult reproductive behavior because growth and survival of young are often affected by the local environment. In terrestrially nesting marbled salamanders, nest elevation is likely important to reproductive success because it is directly related to the time of hatching. We tested the hypothesis that females choose nest sites based on elevation and its correlates by controlling the availability of nesting cover, a potentially important factor in nest site selection which often covaries with elevation. Breeding adults were confined to field enclosures in which natural nesting cover had been removed and replaced with equal proportions of artificial cover in each of three elevation zones. In four enclosures that spanned from lowest to highest areas of a wetland breeding site, females used artificial nesting cover most frequently at low elevations. These results contrast with other studies in which intermediate elevations had highest nest densities, but are consistent with a conceptual model in which opposing selective forces result in locally adapted nest site selection.

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