Individual Life Cycle Research Articles

An overlapping-generations model with data-driven equilibrium behavior

We propose a class of overlapping generations models that can serve as a workhorse for policy analysis. Recent literature identifies several features of key observable economic variables in Europe and the U.S.: the life-cycle path of earnings is hump-shaped, while the aggregate variables — per-capita consumption and labor hours — exhibit a clear time trend. Our class generates non-monotonic life-cycle behavior of labor supply and the desired aggregate trends in all its balanced-growth equilibria (BGE). There is a finite number of these equilibria and at least one of them exists provided a single-generation consumer problem has a solution. The model has a constant-returns-to-scale production, non-trivial depreciation of capital, exogenous labor-saving growth and an arbitrary individual life-cycle productivity. The necessary restrictions imposed on preferences are consistent with those generating the aggregate trends in a representative-agent economy, while ruling out popular specifications such as Cobb–Douglas or CES. We characterize BGE with MaCurdy preferences and solve a parametrized model that yields at least two stationary equilibria with reasonable interest rates. The hump-shaped life-cycle consumption profile can be generated with an additional parameter interpreted as reflecting family structure or a desire for immediate gratification that peaks at mid-life.

Visual fatigue prediction using classification model based on physiological responses of occupants under office lightings

Appropriate management of visual fatigue is crucial for eye health as it significantly impacts life quality throughout an individual's life cycle. The shift to digital tasks in modern office environments has increased occupants' exposure to visual fatigue, leading to various social problems. This study aimed to develop visual fatigue prediction models based on physiological responses and classification algorithms. Experiments were conducted to collect physiological responses and subjective visual fatigue under various lighting environments. Collected data was refined and reorganized as predictor variables by different time windows and target variables by scales. Then, visual fatigue prediction models were developed using supervised machine learning algorithms (i.e., artificial neural network, support vector machine, gradient boosting machine, and random forest). And improved by feature selection and adding subject-label variables. The resulting two-scale and three-scale visual fatigue prediction models demonstrated an average performance of 93.73 % and 94.64 % respectively. This research can contribute to reducing societal costs and enhancing productivity by proposing visual fatigue prediction models that help manage eye health in office environments.

The ageing virus hypothesis: Epigenetic ageing beyond the Tree of Life.

A recent thought-provoking theory argues that complex organisms using epigenetic information for their normal development and functioning must irreversibly age as a result of epigenetic signal loss. Importantly, the scope of this theory could be considerably expanded, with scientific benefits, by analyzing epigenetic ageing beyond the borders of the Tree of Life. Viruses that use epigenetic signals for their normal functioning may also age, that is, present an increasing risk of failing to complete their individual life cycle and to disappear with time. As viruses are ancient, abundant, and infect a considerable diversity of hosts, the ageing virus hypothesis, if verified, would have important consequences for many fields of the Life sciences. Uncovering ageing viruses would integrate the most abundant and biologically central entities on Earth into theories of ageing, enhance virology, gerontology, evolutionary biology, molecular ecology, genomics, and possibly medicine through the development of new therapies manipulating viral ageing.

Historical Perspectives on Older Americans’ Voting and Political Influence: Explorations of the Effects of Individual Aging, Life Cycle, and Generational Cohort

Historical Perspectives on Older Americans’ Voting and Political Influence: Explorations of the Effects of Individual Aging, Life Cycle, and Generational Cohort

Seasonal life cycle of Pintomyia longiflocosa (Diptera: Psychodidae) under semi-controlled conditions in the Huila state, Colombia.

Pintomyia longiflocosa is considered a vector of etiological agents of cutaneous leishmaniasis. The objective of this research was to establish the parameters of the life cycle of Pi. longiflocosa in semi-controlled conditions in a rural area of the Campoalegre municipality, Huila, Colombia. The life cycle of individuals of Pi. longiflocosa, obtained from two cohorts of collected, fed, and individualized females, was monitored during two different times of the year (between February and August 2020 and between July 2020 and January 2021, respectively). Determining parameters associated with the fertility and fecundity, time and attributes of development and survival, and its association with abiotic variables. The average duration of Cycle 1 (C1) and Cycle 2 (C2) was 134.9 and 148.78 days, respectively. The gonotrophic cycle of parental females presented significant differences (p-value <0.05) between C1 and C2 (8.47 and 11.42 days) as well as between fecundity and fertility parameters. The number of days it takes the development of the immature stages between the two cycles studied, also showed significant differences in the larvae II (15.21 and 22.23), larvae III (11.93 and 17.56), and pupae (24.48 and 22.9) stages. During C1, the survival rate was higher and consistent with the productivity of adult individuals (F1), compared to C2. Fecundity and fertility values were significantly higher in C2. Finally, a significant correlation between the number of individuals and temperature was evidenced in C1 while, for C2, there was a negative correlation with precipitation. Significant differences were found in several biological and reproductive parameters between the two cycles monitored. The parameters of the life cycle of Pi. longiflocosa in its natural habitat would be influenced by environmental factors related to the annual seasonality in the sub-Andean rural area, conditioning the temporal distribution of this species and, consequently, the possible transmission of causative agents of cutaneous leishmaniasis.

Impact of skills in early adulthood on lifetime homeownership disparities

This paper shows that skills acquired by early adulthood affect homeownership levels achieved later in life in important ways. The paper examines three sets of skills—cognitive skills, as measured by the Armed Forces Qualifying Test (AFQT) score; non-cognitive skills (specifically, the degree to which people believe that they have control over the outcome of events in their lives), measured by the Rotter score; and social skills, using a Social score based on Deming (2017). Mediation analysis is used to identify both the direct and indirect effects of these skills, as captured by the three different types of scores, on homeownership. We show that the AFQT score measuring cognitive skills not only captures direct effects on the homeownership rate, but even larger indirect effects through the mediator variables—education and income. AFQT scores in early adulthood are shown to be highly predictive of homeownership outcomes, explaining roughly one-quarter to one-third of the disparate outcomes between White, Black, and Hispanic households. We also examine the degree to which the AFQT, Rotter, and Social scores explain variation in homeownership rates over an individual's life cycle. The findings suggest that reducing disparities in educational outcomes would meaningfully contribute to reducing minority homeownership gaps.

Device regulation and surveillance in vascular care: Challenges and opportunities.

Cardiovascular devices are essential for the treatment of cardiovascular diseases including cerebrovascular, coronary, valvular, congenital, peripheral vascular and arrhythmic diseases. The regulation and surveillance of vascular devices in real-world practice, however, presents challenges during each individual product's life cycle. Four examples illustrate recent challenges and questions regarding safety, appropriate use and efficacy arising from FDA approved devices used in real-world practice. We outline potential pathways wherein providers, regulators and payors could potentially provide high-quality cardiovascular care, identify safety signals, ensure equitable device access, and study potential issues with devices in real-world practice.

Detection of earnings manipulations during the corporate life cycle in Central European countries

Research background: The growing trend of financial distress risk worldwide increases the need for effective tools to detect accounting manipulation by stakeholders (debt holders, shareholders, suppliers, and customers). However, the well-known models of accrual earnings management do not reflect the financial specificity of individual life cycle stages and their cash flow patterns. Purpose of the article: The study examines the impact of the corporate life cycle on the reliability of accrual earnings management models and identifies appropriate models for detecting accounting manipulation in Central European countries. Methods: Seven accrual earnings management models were used. They were evaluated based on five criteria: explanatory power (adjusted coefficient of determination), overall significance of the regression model, significance of the regression coefficients, predicted sign of the regression coefficients, and standard errors of the estimated regression coefficients. Finally, a comprehensive scoring model was used to determine the overall quality of the models examined. The study was conducted on a sample of more than 30,000 enterprises from four Central European countries (the Czech Republic, Hungary, Poland, and Slovakia), with data covering the period 2017–2021. The Dickinson non-sequential life cycle model was used to distinguish life cycle stages according to cash flow patterns. Findings &amp; value added: The results of the study suggest that, firstly, discretionary accruals vary across countries as well as over the firm's life cycle; earnings manipulations have an inverted U-shape with mature firms tending to reduce their accounting profit. The reliability of the models examined was poor in the case of start-ups. This reflects the need to distinguish between life cycle stages in the detection of earnings manipulation.

Peranan Edukasi Kesehatan Reproduksi Pada Remaja

Health in adolescence is an important aspect in an individual's life cycle. This period is the time when individuals begin to learn and have functional abilities and health. In terms of health, this period is an important period for reproductive health and the initial formation of healthy living behavior. Based on data from the 2010 Population Census, the group of teenagers aged 10-19 years has a proportion of 18.3% of the total population of Indonesia or around 43.5 million people. The large population of teenagers is an asset and potential for the nation in the future, therefore growth and development must proceed positively and be free from various threatening problems, including reproductive health problems.

Effects of family life cycle events on individual Body Mass Index trajectories: Evidence from China.

Body mass index (BMI) is an important predictor of one's physiological health. China is a family-centric nation compared to Western societies and has already entered an aged society. Exploring the characteristics and patterns of BMI changes during household events in China provides critical insights into the biological and social determinants of health, which can help enhance the scientific validity of health promotion measures and contribute to the realization of healthy aging goals in China. Using data from the China Health and Nutrition Survey (CHNS) from 1993 to 2015, this article utilizes two-level growth curve models with piecewise spline specifications for age to examine the effects of family life cycle events on BMI trajectories for age groups and gender differences. Compared to continuing status, experiencing transition in an individual's family life cycle could lead to more fluctuating variations in their BMI trajectories, generally, there is a faster increase in BMI during youth and a faster decline during old age. As for gender heterogeneity, males are more affected by divorce, widowhood, and empty nest, whereas females' BMI changes are influenced by entering/maintaining marriage and parenthood. A long-term perspective has revealed the significance of family events on BMI throughout the life course. Future research should focus on the nutrition and health of specific populations, especially elderly individuals in vulnerable groups.

Performance of Spodoptera litura (Lepidoptera: Noctuidae) in responses to different amplitudes of alternating temperatures across permissive warm temperature regimes.

Climate change involves changes in the pattern of temperature fluctuations and the frequency and magnitude of thermal extremes. It is essential to investigate how insects respond to increased temperature variations, especially for species that usually experience diel temperature variations extending to thermal performance limits. To explicitly elucidate the effects of sizes of amplitudes of temperature variations, we used daily alternating temperatures with an equivalent mean of 28 °C to investigate the impact of different fluctuation amplitudes (± 0 °C, ± 2 °C, ± 4 °C, and ± 6 °C) across permissive temperature regimes on the performance of Spodoptera litura FabriciusFabricius, a highly destructive polyphagous pest of crops and vegetables in tropical and temperate climates. Amplitudes of temperature fluctuations significantly affected developmental durations, adult life spans, pupal weights, fecundity, and fertility of S. litura. The survival rates from the egg stage to the adult eclosion did not differ significantly across different temperature treatments. The developmental durations of individual life cycles significantly increased with larger amplitudes in 3 fluctuating temperature treatments. The pupal weight was significantly lower and the adult life span was significantly shorter in the ± 6 °C treatment in all treatments. Fecundity and fertility were significantly reduced in the ± 6 °C treatment, making the continuation of generations nearly impossible. The results should provide critical information for understanding the ecology of this widespread pest under diel, seasonal, and global climate changes.

Foraminifera as a model of eukaryotic genome dynamism.

In contrast to the canonical view that genomes cycle only between haploid and diploid states, many eukaryotes have dynamic genomes that change content throughout an individual's life cycle. However, the few detailed studies of microeukaryotic life cycles render our understanding of eukaryotic genome dynamism incomplete. Foraminifera (Rhizaria) are an ecologically important, yet understudied, clade of microbial eukaryotes with complex life cycles that include changes in ploidy and genome organization. Here, we apply fluorescence microscopy and image analysis techniques to over 2,800 nuclei in 110 cells to characterize the life cycle of Allogromia laticollaris strain Cold Spring Harbor (CSH), one of few cultivable foraminifera species. We show that haploidy and diploidy are brief moments in the A. laticollaris life cycle and that A. laticollaris nuclei endoreplicate up to 12,000 times the haploid genome size. We find that A. laticollaris reorganizes a highly endoreplicated nucleus into thousands of haploid genomes through a non-canonical mechanism called Zerfall, in which the nuclear envelope degrades and extrudes chromatin into the cytoplasm. Based on these findings, along with changes in nuclear architecture across the life cycle, we believe that A. laticollaris uses spatio-temporal mechanisms to delineate germline and somatic DNA within a single nucleus. The analyses here extend our understanding of the genome dynamics across the eukaryotic tree of life.IMPORTANCEIn traditional depictions of eukaryotes (i.e., cells with nuclei), life cycles alternate only between haploid and diploid phases, overlooking studies of diverse microeukaryotic lineages (e.g., amoebae, ciliates, and flagellates) that show dramatic variation in DNA content throughout their life cycles. Endoreplication of genomes enables cells to grow to large sizes and perhaps to also respond to changes in their environments. Few microeukaryotic life cycles have been studied in detail, which limits our understanding of how eukaryotes regulate and transmit their DNA across generations. Here, we use microscopy to study the life cycle of Allogromia laticollaris strain CSH, an early-diverging lineage within the Foraminifera (an ancient clade of predominantly marine amoebae). We show that DNA content changes significantly throughout their life cycle and further describe an unusual process called Zerfall, by which this species reorganizes a large nucleus with up to 12,000 genome copies into hundreds of small gametic nuclei, each with a single haploid genome. Our results are consistent with the idea that all eukaryotes demarcate germline DNA to pass on to offspring amidst more flexible somatic DNA and extend the known diversity of eukaryotic life cycles.

Ancestors' Gift: Parental Early Exposure to the Environmentally Realistic Pesticide Mixture Drives Offspring Phenotype in a Larger Extent Than Direct Exposure in the Pacific Oyster, Crassostrea gigas.

Marine organisms are threatened by the presence of pesticides in coastal waters. Among them, the Pacific oyster is one of the most studied invertebrates in marine ecotoxicology where numerous studies highlighted the multiscale impacts of pesticides. In the past few years, a growing body of literature has reported the epigenetic outcomes of xenobiotics. Because DNA methylation is an epigenetic mark implicated in organism development and is meiotically heritable, it raises the question of the multigenerational implications of xenobiotic-induced epigenetic alterations. Therefore, we performed a multigenerational exposure to an environmentally relevant mixture of 18 pesticides (nominal sum concentration: 2.85 μg·L-1) during embryo-larval stages (0-48 hpf) of a second generation (F1) for which parents where already exposed or not in F0. Gene expression, DNA methylation, and physiological end points were assessed throughout the life cycle of individuals. Overall, the multigenerational effect has a greater influence on the phenotype than the exposure itself. Thus, multigenerational phenotypic effects were observed: individuals descending from exposed parents exhibited lower epinephrine-induced metamorphosis and field survival rates. At the molecular level, RNA-seq and Methyl-seq data analyses performed in gastrula embryos and metamorphosis-competent pediveliger (MCP) larvae revealed a clear F0 treatment-dependent discrimination. Some genes implicated into shell secretion and immunity exhibited F1:F0 treatment interaction patterns (e.g., Calm and Myd88). Those results suggest that low chronic environmental pesticide contamination can alter organisms beyond the individual scale level and have long-term adaptive implications.

Sex-biased phenotypic plasticity affects sexual dimorphism patterns under changing environmental conditions

Sexual dimorphism is almost ubiquitous in animals. A common pattern observed across multiple taxa involves differences in development time (sexual bimaturism) and body size (sexual size dimorphism) between conspecific males and females. Furthermore, a strict association of dimorphism at these traits has been documented in several taxa, where the sex showing shorter development time also has a smaller body size than the other sex. Growth and development are strongly dependent on environmental conditions during individual life-cycle in ectotherms, inducing considerable phenotypic plasticity. However, how phenotypic plasticity affects the association between sexual dimorphism in development time and body size remains unclear. Here, we tracked development time, body size, and body mass throughout the ontogeny of the mosquito Aedes mariae. The larval development of this species is strictly linked to Mediterranean Sea rock-pools, whose highly variable environmental conditions over minimal time frames make this organism-environment system ideal for exploring plasticity-led eco-evolutionary processes. We found differential plasticity between males and females, dissolving the link between dimorphism in development time and body size under increasing temperature and decreasing salinity conditions. These findings contrast with the current hypotheses proposed to explain the origin of the association between sexual bimaturism and sexual size dimorphism, highlighting the condition dependence of sexual dimorphism patterns and the need to consider phenotypic plasticity in future studies on their evolution.

The impact of salps (Salpa thompsoni) on the Antarctic krill population (Euphausia superba): an individual-based modelling study

BackgroundKrill (Euphausia superba) and salps (Salpa thompsoni) are key macrozooplankton grazers in the Southern Ocean ecosystem. However, due to differing habitat requirements, both species previously exhibited little spatial overlap. With ongoing climate change-induced seawater temperature increase and regional sea ice loss, salps can now extend their spatial distribution into historically krill-dominated areas and increase rapidly due to asexual reproduction when environmental conditions are favorable. Understanding the potential effects on krill is crucial, since krill is a species of exceptional trophic significance in the Southern Ocean food web. Negative impacts on krill could trigger cascading effects on its predators and prey. To address this question, we combined two individual-based models on salps and krill, which describe the whole life cycle of salp individuals and the dynamic energy budget of individual krill. The resulting new model PEKRIS (PErformance of KRIll vs. Salps) simulates a krill population for 100 years under varying chlorophyll-a concentrations in the presence or absence of salps.ResultsAll of the investigated krill population properties (abundance, mean length, and yearly egg production) were significantly impacted by the presence of salps. On the other hand, salp density was not impacted if krill were present. The medians of krill population properties deviated during variable maximum chlorophyll-a density per year when salps were introduced by − 99.9% (− 234 individuals per 1000 m3) for krill density, − 100% (− 22,062 eggs per 1000 m3) for krill eggs and − 0.9% (− 0.3 mm) for mean length of krill.ConclusionsIf both species compete for the same food resource in a closed space, salps seem to inhibit krill populations. Further simulation studies should investigate whether this effect prevails if different phytoplankton sizes and consumption preferences of krill are implemented. Furthermore, direct predation of the two species or consumption of krill fecal pellets by salps could change the impact size of the food competition.

Repertoire and vocal behaviour of the grey heron (Ardea cinerea) during the breeding season: a case study in the western Po Valley

The grey heron is an extensively studied and widely distributed colonial bird species in the Old World; however, relevant information on the role played by vocalisations during the life cycle of individuals is still lacking. This research aimed to deepen the available knowledge on the repertoire and vocal behaviour of adults during the breeding season, through a bioacoustic approach and choosing as study areas two heronries in different environmental contexts. Colonies were monitored 2 days a week each, for 9 weeks, from 8:00 am to 6:00 pm (360 hr of sampling). Results showed that adults use a wide range of call types, mainly related to courtship and the reproductive phase. Vocalisations are emitted especially by males and are a key element during mate attraction, nest building, in breeding events and in strengthening bonds within pairs. Most vocalisations are expressed in the first weeks of the breeding cycle, concurrently with the maximum number of courtship males, which exhibit most of the detected sound categories and emit calls with lower frequencies than females. Moreover, these vocalisations are expressed to a greater extent in the heronry characterized by an important forest component, where an almost entirely exclusive sound category was detected. In conclusion, the results suggest a possible correlation between vocal behaviour and female choice. The wide variety of sound signals and the high rate of calls produced by males during attraction and courtship displays, together with the acoustic characteristics of the signals, could provide honest estimates of the quality of emitters.

Natural intelligence and the ‘economy’ of social emotions: A connection with AI sentiment analysis

By approaching the concept of Natural Intelligence a new path may be open in a variety of theoretical and applied problems on social emotions. There is no doubt that intelligence emerges as a biological/informational phenomenon, although paradoxically a consistent elaboration of that concept has been missing. Regarding emotions, they have been keeping an unclear status, being often restricted to the anthropological or to ethological approaches closer to the behaviorist paradigm. Herein we propose a different track, centered in the life cycle advancement. The life cycle in its integrity becomes the nucleus of natural intelligence's informational processes, including the consistent expression of emotions along the maximization of fitness occasions. In human societies, the overall ‘economy’ of social emotions is manifest, showing up in the conspicuous interplay between bonding processes and different classes of social emotions. The essential link between natural intelligence, emotions, and the life cycle of individuals may harmonize with current progresses – and blind spots – of artificial intelligence fields such as ‘sentiment analysis.’

Monocytes and macrophages: emerging mechanisms and novel therapeutic targets in pulmonary fibrosis.

Pulmonary fibrosis results from a plethora of abnormal pathogenetic events. In idiopathic pulmonary fibrosis (IPF), inhalational, environmental, or occupational exposures in genetically and epigenetically predisposed individuals trigger recurrent cycles of alveolar epithelial cell injury, activation of coagulation pathways, chemoattraction, and differentiation of monocytes into monocyte-derived alveolar macrophages (Mo-AMs). When these events happen intermittently and repeatedly throughout the individual's life cycle, the wound repair process becomes aberrant leading to bronchiolization of distal air spaces, fibroblast accumulation, extracellular matrix deposition, and loss of the alveolar-capillary architecture. The role of immune dysregulation in IPF pathogenesis and progression has been underscored in the past mainly after the disappointing results of immunosuppressant use in IPF patients; however, recent reports highlighting the prognostic and mechanistic roles of monocytes and Mo-AMs revived the interest in immune dysregulation in IPF. In this review, we will discuss the role of these cells in the onset and progression of IPF, as well as potential targeted therapies.

Creative productivity of ukrainian artists in the conditions of war

The article describes the results of creative productivity research in Ukrainian artists in the conditions of war as a traumatic event. The correlation between war and creative productivity has not been extensively studied in the context of psychology. The most famous so far is the research of Karol Borowiecki and John Hagan, who investigated the individual life cycle of composers and changes in their creative productivity in connection with wars. After the beginning of the full-scale invasion, Ukrainian researchers Lazarenko and Bobrova studied the emotional state of Ukrainians, a result which the data obtained indicated the presence of anxiety, fear, fatigue, and exhaustion, which led to a decrease in productive activity in people. The value and relevance of the research are related to the fact that today there are practically no studies devoted to the study of the relationship between creativity and emotional state in war conditions, but this knowledge will bring us closer to the creativity mechanism understanding. The research involved 37 artists who were on the territory of Ukraine all the time during the year: from the beginning of the full-scale invasion — 02/24/2022 to 02/24/2023. To evaluate and compare creative productivity, data was taken on the number of artistic works for the period of 2021-2022 and 2022-2023. According to the results of the survey, 70.27% of respondents demonstrated an increase in creative productivity, which is associated with a bad mood, that is, a negative emotional state. A moderate correlation between the evaluation of the emotional state and creative productivity was revealed, and it was found that in the conditions of war, the features of the emotional state and energy are a certain criterion for the growth of creative productivity. From a neurobiological point of view, the inverse correlation between mental activation and creative productivity is explained.

Lifelong Education in Economics, Business and Management Research: Literature Review

Abstract Background Lifelong education includes formal and nonformal forms of learning during an individual's life cycle for the conscious and continuous development of one's quality and the quality of life in society. Objectives The goal of the research is to identify the most frequent research topics related to lifelong education in economics, business, and management research using a systematic literature review. Methods/Approach The study analysed 272 lifelong education papers in Business, Management, and Economics journals using bibliometric analysis, text mining, and Provalis Wordstat content analysis, identifying frequent journals, authors, nations, and funding entities. Results Research on lifelong education, focusing on older adults, critical thinking, quality of life, poverty reduction, professional training, and human capital, is primarily published in the International Journal of Lifelong Education. Four clusters have been identified. Conclusions The number of lifelong education papers is increasing, primarily published in educational journals. The most common keywords highlight its focus on human capital, supporting economic and social development.