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STUDY QUESTION Do the mothers of twins and singletons differ regarding post-partum and old-age mortality? SUMMARY ANSWER Twin deliveries were associated with higher post-partum maternal mortality than singleton deliveries, but the lifetime post-partum mortality risk was similar for mothers of twins and singletons; survival of twinners was higher than survival of the mothers of singletons after the 67th lifespan percentile. WHAT IS KNOWN ALREADY Twinning is typically associated with higher post-partum maternal mortality. The evidence about whether twinning incurs long-term survival costs of reproduction or is a trait pertinent to long-lived women is scarce and contradictory. STUDY DESIGN, SIZE, DURATION The study is based on the data of the Estonian Family Register (operating from 1926 to 1943) and involves 5565 mothers of twins and 119 613 mothers of singletons born between 1850 and 1899. The subset for comparing maternal lifespans included 1703–1884 mothers of twins and 19 747–36 690 mothers of singletons. PARTICIPANTS/MATERIALS, SETTING, METHODS Post-partum maternal mortality was analyzed in the whole sample (including mothers of a single child) by logistic regression. Most of the analyses were performed in samples where each mother of twins was matched against mothers of singletons based on parity (or number of deliveries), urban versus rural and inland versus coastal origin, whether their lifespan was known, date of birth and age at first birth. Lifespans were compared in linear mixed models. Quantile regression was used to analyze age-dependent variations in maternal mortality rates. All models were adjusted for relevant biodemographic covariates. MAIN RESULTS AND THE ROLE OF CHANCE The twinning rate in the whole sample was 4.4%. During the year after giving birth, maternal mortality for twin deliveries was 0.75% (17/2273) and 0.37% (449/122 750) for singleton deliveries (OR = 2.05, 95% CI = 1.21–3.23). However, the lifetime post-partum mortality risk for mothers of twins (0.51%; 28/5557) and singletons (0.37%; 438/119 466) did not differ significantly (OR = 1.38, 95% CI = 0.91–1.98). The life spans of the mothers of twins and singletons did not differ in matched samples. Past the 67th lifespan percentile, the odds of survival were significantly higher for mothers of twins than mothers of singletons, as indicated by non-overlapping 95% confidence intervals. LIMITATIONS, REASONS FOR CAUTION Relatively low number of individuals (22 802–28 335) with known age at death in matched datasets due to discontinuation of the register after 1943. WIDER IMPLICATIONS OF THE FINDINGS The finding that mothers of twins had higher odds of old-age survival than mothers of singletons is consistent with the contention that twinners represent a non-random subset of women whose robust phenotypic quality allows them to outlive the mothers of singletons in old age. STUDY FUNDING/COMPETING INTEREST(S) The study was funded by the Estonian Research Council grants PRG1137, PRG2248, and PSG669. The authors declare no competing interests. TRIAL REGISTRATION NUMBER N/A. [ABSTRACT FROM AUTHOR]

Aging is a complex process influenced by internal and external factors. Oxidative stress damages DNA, leading to 8-hydroxy-2' deoxyguanosine formation (8-OHdG). Telomere shortening is considered a biomarker of aging and oxidative stress may enhance its attrition. The ability to manage and repair oxidative stress varies among species and life histories. Avian species, such as Psittacidae birds, exhibit exceptional lifespans despite their physiological characteristics that might suggest otherwise. This study investigates 8-OHdG levels in serum samples from long- and short-lived birds of the order Psittaciformes, examining their relationship with telomere length and antioxidant capacity based on lifespan strategies. Among 43 individuals analyzed 26 belonged to the "long-lived species" group and 17 belonged to the "short-lived species" one. Relative telomere length (rTL) was measured in DNA isolated from whole blood by qPCR, and oxidative stress markers, such as Total Antioxidant Capacity (TAC) and 8-OHdG, were determined by spectrophotometry in serum samples. Long-lived birds had longer rTL than short-lived ones [1.308 ± 0.11 vs. 0.565 ± 0.13, (p < 0.001)]. On the contrary, short-lived birds showed more DNA damage than their counterparts [3.847 ± 0.351 vs. 2.012 ± 0.308, respectively, (p < 0.001)]. Old birds had shorter rTL than young ones, for both longevity groups (p < 0.001). Although no correlation was found between 8-OHdG levels and age, nor 8-OHdG and telomere length, long-lived birds exhibited 75.42-unit increased TAC levels when increased 8-OHdG concentrations (p = 0.046). These findings highlight distinct patterns of telomere length and oxidative stress influenced by lifespan strategies among avian longevity groups. [ABSTRACT FROM AUTHOR]

Healthy aging has emerged as a crucial issue with the increase in the geriatric population worldwide. Food-derived sulfur-containing amino acid ergothioneine (ERGO) is a potential dietary supplement, which exhibits various beneficial effects in experimental animals although the preventive effects of ERGO on aging and/or age-related impairments such as frailty and cognitive impairment are unclear. We investigated the effects of daily oral supplementation of ERGO dissolved in drinking water on lifespan, frailty, and cognitive impairment in male mice from 7 weeks of age to the end of their lives. Ingestion of 4 ~ 5 mg/kg/day of ERGO remarkably extended the lifespan of male mice. The longevity effect of ERGO was further supported by increase in life and non-frailty spans of Caenorhabditis elegans in the presence of ERGO. Compared with the control group, the ERGO group showed significantly lower age-related declines in weight, fat mass, and average and maximum movement velocities at 88 weeks of age. This was compatible with dramatical suppression by ERGO of the age-related increments in plasma biomarkers (BMs) such as the chemokine ligand 9, creatinine, symmetric dimethylarginine, urea, asymmetric dimethylarginine, quinolinic acid, and kynurenine. The oral intake of ERGO also rescued age-related impairments in learning and memory ability, which might be associated with suppression of the age-related decline in hippocampal neurogenesis and TDP43 protein aggregation and promotion of microglial shift to the M2 phenotype by ERGO ingestion. Ingestion of ERGO may promote longevity and healthy aging in male mice, possibly through multiple biological mechanisms. [ABSTRACT FROM AUTHOR]

Anti‐aging research has made significant strides in identifying treatments capable of extending lifespan across a range of organisms, from simple invertebrates to mammals. This review showcases the current state of anti‐aging interventions, highlighting the lifespan extensions observed in animal models through various treatments and the challenges encountered in translating these findings to humans. Despite promising results in lower organisms, the translation of anti‐aging treatments to human applications presents a considerable challenge. This discrepancy can be attributed to the increasing complexity of biological systems, species‐specific metabolic and genetic differences, and the redundancy of metabolic pathways linked to longevity. Our review focuses on analyzing these challenges, offering insights into the efficacy of anti‐aging mechanisms across species and identifying key barriers to their translation into human treatments. By synthesizing current knowledge and identifying gaps in translatability, this review aims to underscore the importance of advancing these therapies for human benefit. Bridging this gap is essential to assess the potential of such treatments in extending the human healthspan. [ABSTRACT FROM AUTHOR]

Age determination is an important tool in fishery research and management, providing key data for growth modelling and population dynamics. Knowledge of longevity and growth performance of fishes is especially important in defining their life history strategies. In this review we summarize all published data on the ageing of notothenioid fishes of the Southern Ocean, and evaluate factors influencing growth performance and longevity in a phylogenetic context. Most age estimates in notothenioids are based on otolith readings and application of the von Bertalanffy growth model to describe body growth throughout the life span. Growth performance and longevity both exhibit wide ranges between 3.5 and 5.5 and 7–52 years, respectively. However, growth performance is positively related to asymptotic fish size, whereas longevity is negatively related to the Brody growth rate coefficient. Lifestyle and latitudinal and depth distributions are the main factors influencing the life history traits of notothenioids. Growth performance significantly increases from benthic to pelagic species and declines toward higher latitudes. Conversely, longevity is higher in pelagic species and shows a positive trend with latitude and depth of occurrence. There is a trend toward an increase of both traits in the phylogenetically derived families, such as bathydraconids and channichthyids. Compared to Arctic fishes, notothenioids have similar values for growth performance and longevity. Currently the major gaps in our knowledge of age determination of notothenioids are the lack of validation of age estimates and the relatively low number of species studied. Future efforts have to provide more reliable and objective estimates of age through multiple comparisons among different laboratories and application of validation tools. [ABSTRACT FROM AUTHOR]

Children with spinal muscular atrophy (SMA) are now living longer as a result of advancements in pharmaceutical and medical interventions. There is a paucity of research regarding therapeutic interventions to support this population to be independent and participate in life activities that are most important to them. The aim of this case report is to explore the use of the Cognitive Orientation to daily Occupational Performance (CO-OP) approach to support a child with SMA type 1 to achieve their functional and participation goals. This is a retrospective case study. A 7-year-old girl with SMA type 1 received ten 1 h sessions of CO-OP, weekly in the home and community settings with a physiotherapist. Clinically meaningful improvements were found in goal performance and satisfaction on the Canadian Occupational Performance Measure (COPM) and Performance Quality Rating Scale (PQRS). Despite the progressive nature of SMA, the CO-OP approach was able to support goal attainment. Given medical advances are leading to a longer life span for children with neuromuscular conditions, further research is needed to investigate the efficacy of functional and participation-based interventions, including impact on quality of life and self-efficacy. [ABSTRACT FROM AUTHOR]

The genetic pathways that modulate ageing in multicellular organisms are typically highly conserved across wide evolutionary distances. Recently RNA polymerase III (Pol III) was shown to promote ageing in yeast, C. elegans and D. melanogaster. In this study we investigated the role of Pol III in mammalian ageing using C57BL/6N mice heterozygous for Pol III (Polr3b+/−). We identified sexually dimorphic, organ‐specific beneficial as well as detrimental effects of the Polr3b+/− mutation on health. Female Polr3b+/− mice displayed improved bone health during ageing, but their ability to maintain an effective gut barrier function was compromised and they were susceptible to idiopathic dermatitis (ID). In contrast, male Polr3b+/− mice were lighter than wild‐type (WT) males and had a significantly improved gut barrier function in old age. Several metabolic parameters were affected by both age and sex, but no genotype differences were detected. Neither male nor female Polr3b+/− mice were long‐lived compared to WT controls. Overall, we find no evidence that a reduced Pol III activity extends mouse lifespan but we do find some potential organ‐ and sex‐specific benefits for old‐age health. [ABSTRACT FROM AUTHOR]

Mitochondria are essential for survival and as such, impairments in organelle homeostasis significantly accelerate age‐related morbidity and mortality. Here, we determined the contribution of bioenergetic efficiency to life span and health span in Drosophila melanogaster utilizing the mitochondrial uncoupler BAM15. Life span was determined in flies fed a normal diet (ND) or high fat diet (HFD) supplemented with vehicle or BAM15. Locomotor function was determined by negative geotaxis assay in middle‐aged flies fed vehicle or BAM15 under ND or HFD conditions. Redox capacity (high‐resolution respirometry/fluorometry), citrate synthase (enzyme activity), mtDNA content (qPCR), gene expression (qPCR), and protein expression (western blot) were assessed in flight muscle homogenates of middle‐aged flies fed vehicle or BAM15 ND. The molar ratio of H2O2 and O2 (H2O2:O2) in a defined respiratory state was calculated as a measure of redox balance. BAM15 extended life span by 9% on ND and 25% on HFD and improved locomotor activity by 125% on ND and 53% on HFD. Additionally, BAM15 enhanced oxidative phosphorylation capacity supported by pyruvate + malate, proline, and glycerol 3‐phosphate. Concurrently, BAM15 enhanced the mitochondrial H2O2 production rate, reverse electron flow from mitochondrial glycerol‐3‐phosphate dehydrogenase (mGPDH) to Complex I, mGPDH, and Complex I without altering the H2O2:O2 ratio. BAM15 upregulated transcriptional signatures associated with mitochondrial function and fitness as well as antioxidant defense. BAM15‐mediated restriction of bioenergetic efficiency prolongs life span and health span in Drosophila fed a ND or HFD. Improvements in life span and health span in ND were supported by synergistic enhancement of muscular redox capacity. [ABSTRACT FROM AUTHOR]

An understanding of biological fitness is central to theory and practice in ecology and evolution, yet fitness remains an elusive concept to define and is challenging to measure accurately. Fitness reflects an individual's ability to pass its alleles on to subsequent generations. Researchers often quantify proxies for fitness, such as survival, growth, or reproductive success. However, it can be difficult to determine lifetime fitness, especially for species with long life spans. The abiotic and biotic environment strongly affects the expression of fitness, which means that fitness components can vary through both space and time. This spatial and temporal heterogeneity results in the impressive range of adaptations that we see in nature. Here, we review definitions of fitness and approaches to measuring fitness at the level of genes, individuals, genotypes, and populations and highlight that fitness is a key concept linking ecological and evolutionary thought. [ABSTRACT FROM AUTHOR]

We report on a male platypus (Ornithorhynchus anatinus) who was tagged in November 2000 at the age of 1 year and recaptured in September 2023, when nearly 24 years old, in a small creek system in Melbourne's southeastern suburbs. By comparison, a female platypus recently reached the age of 30 years in captivity, though with signs of ageing that may have precluded her survival if she were living in the wild. Ten other captive individuals have lived to an age of more than 20 years in recent decades. A new platypus longevity record in the wild (nearly 24 years) has been confirmed for a male living in a creek in Melbourne's southeastern suburbs. In captivity, a female platypus recently reached the age of 30 years at Healesville Sanctuary. Photograph by Barry Baker. [ABSTRACT FROM AUTHOR]

The Hebrew Bible is often read tliat men once lived nearly a thousand years. Then, after a cataclysm in the form of a flood, their life spmis followed an exponential decline to contemporary values, but no explanation for this decline was offered. Recently, it lias been suggested tlmt the decline can be attributed to marriage of die descendants of Noah to n population of short-lived survivors of the flood. This journal has previously published a paper that argued that the numbers expressing these longevities have the properties of real numbers and none of the properties of artficial or made-up numbers, ami that the reasons for doubting the biblical numbers do not survive close examination. Moreover, recent work argues that humans may ultimately have biblicnl longevities. Tlze present article shows that the intermarriage explanation for the decay of longevities is plausible. [ABSTRACT FROM AUTHOR]

Life span uncertainty (longevity risk) impacts several economic decisions. Individuals can form and revise their survival beliefs making use of behavioral heuristics. We propose a model of sentiment, in which individuals are assumed to switch between optimistic and pessimistic expectations of their health. When optimism is persistent in the face of health shocks, or when individuals are more likely to change their sentiment from pessimistic to optimistic than otherwise, our model predicts survival underestimation at young ages and overestimation at old ages. An empirical analysis based on the longitudinal data from Survey of Health, Ageing and Retirement in Europe validates our model. [ABSTRACT FROM AUTHOR]

Gerontology research on anti-aging interventions with drugs could be an answer to age-related diseases, aiming at closing the gap between lifespan and healthspan. Here, we present two methods for assaying chronological lifespan in human cells: (1) a version of the classical outgrowth assay with quantitative assessment of surviving cells and (2) a version of the PICLS method (propidium iodide fluorescent-based measurement of cell death). Both methods are fast, simple to conduct, cost-effective, produce quantitative data for further analysis and can be used with diverse human cell lines. Whereas the first method is ideal for validation and testing the post-intervention reproductive potential of surviving cells, the second method has true high-throughput screening potential. The new technologies were validated with known anti-aging compounds (2,5-anhydro-d-mannitol and rapamycin). Using the high-throughput screening method, we screened a library of 162 chemical entities and identified three compounds that extend the longevity of human cells. [ABSTRACT FROM AUTHOR]

BACKGROUND: Auricularia polytricha (AP) is traditionally known for its medicinal properties, and linoleic acid (LA) is the prominent component in AP. OBJECTIVE: To understand the anti-aging and stress resistance mechanism induced by AP in Caenorhabditis elegans. METHODS: C. elegans (wild-type (N2), transgenic, and mutant strains) were treated with AP and LA and monitored for lifespan and stress resistance through physiological assays, fluorescence microscopy, and qPCR analysis. Molecular docking studies were employed to identify the interaction mode of LA with DAF-16 and SKN-1. RESULTS: Ethanol extract of AP (APE) was non-toxic and could induce an anti-aging mechanism, as it could extend the lifespan of nematode worms. This was dependent on PMK-1 and DAF-16 as APE could not extend the lifespan of these gene-specific mutants apart from extending the expression of these genes in wild-type nematodes, which was evident from qPCR analysis. LA, too, had a similar effect on the lifespan of wild-type and mutant worms, which further supported the findings. Molecular docking studies pointed to the role of DAF-16 and SKN-1 in regulating the effect of APE. APE also exhibited antioxidant and anti-inflammatory mechanisms as it significantly extended the lifespan in worms exposed to UV-B-induced oxidative stress, thereby showing a protective effect. APE could regulate SKN-1, which was evident from qPCR analysis and the fluorescence of skn-1:GFP transgenic strain. Further qPCR analysis of candidate regulatory genes exhibited antioxidant mechanisms induced by APE. CONCLUSION: APE was observed to induce anti-aging efficacy via SKN-1 and DAF-16. [ABSTRACT FROM AUTHOR]

Although several antidepressants have been identified as potential geroprotectors, the effect and mechanism of fluoxetine, a representative selective serotonin reuptake inhibitor, on longevity have not been fully elucidated. Here, we found that fluoxetine promoted longevity in Caenorhabditis elegans with a concomitant extension of a healthy life span as indicated by increasing mobility, reducing fertility and lipofuscin accumulation, and enhanced resistance to different abiotic stresses. Fluoxetine increased the level of reactive oxygen species (ROS), and antioxidant N-acetylcysteine abolished ROS elevation and the pro-longevity effect of fluoxetine. Additionally, fluoxetine extended life span through the daf-2 - sod-3 pathway in daf-16 -dependent and -independent manners, and fluoxetine-induced life-span extension was abolished in C. elegans sod-3 , daf-2 , and daf-16 mutants. In conclusion, these findings suggest that fluoxetine can promote health and longevity in C. elegans via the interaction of ROS and insulin signaling. [ABSTRACT FROM AUTHOR]

Polyamines (PAs) are important molecules that determine cell longevity or death. Studies have shown that nutritional supplementation with spermidine can reduce age-related pathology and increase life span in a number of organisms, including humans. In addition, applying PAs to plants prevents their senescence. This review aims to provide an integrated understanding of the regulation of PA metabolism and its effect(s) on cell homeostasis. PA metabolism is universal for plants and animals. Research has shown that increased levels of PA synthesizing enzymes are associated with cell proliferation, whereas activation of the PA catabolic pathway increases oxidative stress and leads to aging/senescence due to cellular damage. Intracellular PA levels are regulated at the transcriptional and translational levels of the PA metabolic genes. The cis-acting regulatory elements and transcription factors determine the tissue-, developmental stage-, and stress-specific expression of a gene. At the translational level, it is regulated by miRNAs targeting mRNAs for cleavage or translational suppression. The byproducts of PA metabolism, such as hypusine and acrolein, are important for cell survival or death. PAs and their metabolic enzymes play several other important roles in plant and animal physiology via their effects on chromatin condensation, histone acetylation, histone deacetylation, transmethylation, and protein-protein interactions. This review focuses on the role(s) of PAs as universal bioregulators in processes across kingdoms, with specific reference to regulation of cellular longevity and death. [ABSTRACT FROM AUTHOR]

The morphogenetic consequences of exposure to short-term heat stress (STHS) in two housefly strains mass-selected for lifespan were studied based on the assessment of adult wing variability by geometric morphometrics. Significant differences in the size and shape of the wing between the control and impact groups of different genders in the strains were revealed. Shg (short lived) and Lg (long-lived). The STHS effect manifested in an increase in the size of the wing and a directed change in its shape. The between-group hierarchy of gender and stress-induced differences is expressed in the same way in both strains of flies. The range of linear differences is significantly higher than the gender differences, which, in turn, are higher than the level of stress-induced ones. Instability of imago wing development (Vm) in Shg was significantly higher than the Lg strains, and higher in all groups of females, but in most cases significantly lower in impact groups (taking into account the increase in size, the latter may be associated with the effect of hormesis). It is hypothesized that the directed morphogenetic effects of STHS are based on latent species modifications, the appearance of which in the phenotype is due to stress-induced epigenetic genome rearrangements that cause similar morphological changes in the wing in groups of adult males and females of both strains. The phenotypic plasticity of strains during selection for different lifespans and the changes induced by STHS directly indicate the reality of stress-induced rapid morphogenetic rearrangements under a sharp change in environmental conditions. [ABSTRACT FROM AUTHOR]

Living longer without simultaneously extending years spent in good health ("health span") is an increasing societal burden, demanding new therapeutic strategies. Hydrogen sulfide (H2S) can correct disease-related mitochondrial metabolic deficiencies, and supraphysiological H2S concentrations can pro health span. However, the efficacy and mechanisms of mitochondrion-targeted sulfide delivery molecules (mtH2S) administered across the adult life course are unknown. Using a Caenorhabditis elegans aging model, we compared untargeted H2S (NaGYY4137, 100 µM and 100 nM) and mtH2S (AP39, 100 nM) donor effects on life span, neuromuscular health span, and mitochondrial integrity. H2S donors were administered from birth or in young/middle-aged animals (day 0, 2, or 4 postadulthood). RNAi pharmacogenetic interventions and transcriptomics/network analysis explored molecular events governing mtH2S donor-mediated health span. Developmentally administered mtH2S (100 nM) improved life/health span vs. equivalent untargeted H2S doses. mtH2S preserved aging mitochondrial structure, content (citrate synthase activity) and neuromuscular strength. Knockdown of H2S metabolism enzymes and FoxO/daf-16 prevented the positive health span effects of mtH2S, whereas DCAF11/wdr-23 - Nrf2/skn-1 oxidative stress protection pathways were dispensable. Health span, but not life span, increased with all adult-onset mtH2S treatments. Adult mtH2S treatment also rejuvenated aging transcriptomes by minimizing expression declines of mitochondria and cytoskeletal components, and peroxisome metabolism hub components, under mechanistic control by the elt-6/elt-3 transcription factor circuit. H2S health span extension likely acts at the mitochondrial level, the mechanisms of which dissociate from life span across adult vs. developmental treatment timings. The small mtH2S doses required for health span extension, combined with efficacy in adult animals, suggest mtH2S is a potential healthy aging therapeutic. [ABSTRACT FROM AUTHOR]

The current scientific and technological development, which has made it possible to increase life span in healthy conditions, has led to a reconfiguration of life and old age. This has raised new questions about the meaning of this extended life. The article analyzes how, through youthfulness and consumerism, the ideal of eternal youth has been enthroned, by denigrating old age, medicalizing life, and creating an obsession with cosmetics and aesthetics. Ultimately, it is evident that the search for the abolition of old age responds to the attempt to dissolve death. [ABSTRACT FROM AUTHOR]

The composites of NiCo2O4 with unique structures were substantially investigated as promising electrodes. In this study, the unique structured nanosheets anchored on nickel foam (Ni foam) were prepared under the hydrothermal technique of NiCo2O4 and subsequent preparation of Co(OH)2. The Co(OH)2@NiCo2O4 nanosheet composite has demonstrated higher specific capacitances owing to its excellent specific surface region, enhanced rate properties, and outstanding electrical conductivities. Moreover, the electrochemical properties were analyzed in a three-electrode configuration to study the sample material. The as-designed Co(OH)2@NiCo2O4 nanosheet achieves higher specific capacitances of 1308 F·g−1 at 0.5 A·g−1 and notable long cycles with 92.83% capacity retention over 6000 cycles. The Co(OH)2@NiCo2O4 nanosheet electrode exhibits a long life span and high capacitances compared with the NiCo2O4 and Co(OH)2 electrodes, respectively. These outstanding electrochemical properties are mainly because of their porous construction and the synergistic effects between NiCo2O4 and Co(OH)2. Such unique Co(OH)2@NiCo2O4 nanosheets not only display promising applications in renewable storage but also reiterate to scientists of the unlimited potential of high-performance materials. [ABSTRACT FROM AUTHOR]

Aging is the root cause of several pathologies like neurological and cardiovascular diseases. Identifying compounds that improve health span and extend life span, called geroprotectors, could be crucial to preventing or at least delaying the onset of age-related diseases. In this regard, the nematode Caenorhabditis elegans (C. elegans) is emerging as an easy, efficient, low-cost model system to screen natural products and identify novel geroprotectors. Phenolic acids can be found in a wide range of natural products that are part of the human diet. Vanillic acid (VA) is a phenolic acid that has previously been attributed with antioxidant, anti-inflammatory, and neuroprotective features. To determine whether these beneficial health effects amount to an extension of health span and life span, in this work, we thoroughly explore the effect of VA on C. elegans stress resistance and life span. We found that VA increases thermotolerance (19.4%), reduces protein aggregation (between 30% and 40%), improves motility, and extends life span by almost 50%, an extent hardly ever achieved with a natural compound. The increased thermotolerance induced by VA is independent of the insulin/insulin-like growth factor-1 signaling pathway but requires heat shock factor-1 and is associated with increased heat shock protein-4 (HSP-4) and hsp-16.2 expression. These results provide new insight into understanding the therapeutical properties of VA and warrant further investigation of VA as a novel geroprotector. [ABSTRACT FROM AUTHOR]

Dietary restriction (DR) is cited as the most reliable means of extending life span in a wide range of taxa, yet the evolutionary basis of the DR effect on life span remains unclear. The resource reallocation hypothesis proposes that the longevity-extending response of DR is adaptive and stems from the reallocation of resources from reproduction to somatic maintenance under food-limited conditions. However, if DR continues for multiple generations, such a response becomes maladaptive, and genotypes with higher fecundity should be selectively favored over genotypes with longer longevity. To test this prediction, we exposed replicate populations of the rotifer Brachionus dorcas , a model organism for aging and experimental evolution studies, to DR and ad-libitum (AL) diets for 100 days. During the selection experiment, AL-selected populations showed higher growth rates and mictic ratios than DR-selected populations. After approximately 27 asexual generations of selection, populations with a DR selection history had a higher net reproductive rate but lower body volume and ingestion rate in the absence of survival costs than populations with an AL selection history when they were assayed on an AL diet. Our results are inconsistent with the prediction that evolution on sustained DR increases reproduction and reduces life span, and show for the first time that sustained DR selects for clones with higher energy investment in reproduction but lower investment in somatic growth. [ABSTRACT FROM AUTHOR]

The human life span has been markedly extended since the 1900s, but it has not brought healthy aging to everyone. This increase in life expectancy without an increase in healthspan is a major global concern that imposes considerable health care budgets and degrades the quality of life of older adults. Dietary interventions are a promising strategy to increase healthspan. In this study, we evaluated whether a Gardenia jasminoides Ellis fruit ethanol extract (GFE) increases the life span of Caenorhabditis elegans (C. elegans). Treatment with 10 mg/mL GFE increased the life span by 27.1% when compared to the vehicle group. GFE (10 mg/mL) treatment improved healthspan-related markers (pharyngeal pumping, muscle quality, age–pigment, and reactive oxygen species accumulation) and exerted a protective effect against amyloid β 1–42 toxicity. These effects of GFE are related to the inhibition of insulin/IGF-1 signaling and activation of SKN-1/Nrf, thereby promoting the expression of stress resistance-related genes. In addition, treatment with 10 mM geniposide, the most abundant component of GFE, improved healthspan-related markers and increased life span by 18.55% when compared to the vehicle group. Collectively, these findings demonstrate that GFE and its component geniposide increase the life span along with healthspan in C. elegans. [ABSTRACT FROM AUTHOR]

Curcumin is well known as a potent antioxidant and free radical scavenger and has great potential for anti-aging applications. In this study, we investigate the molecular mechanism of curcumin in prolonging the lifespan of C. elegans. Four concentrations of curcumin (10, 25, 50, and 100 µM) were administered, and the optimal treatment concentration was determined by analyzing the nematode lifespan, physiology, and biochemistry. Additionally, RNA-seq and qRT-PCR were performed to explore the antioxidant effect of curcumin and its underlying mechanism. Results revealed that curcumin could significantly improve the survival capacity of C. elegans without influencing its growth. Curcumin was observed to significantly decrease the levels of reactive oxygen species (ROS) under extreme conditions such as heat stress and paraquat stress. In addition, curcumin increased the amount of nematode mitochondrial DNA (mtDNA) replication. RNA-seq results revealed that the underlying mechanism of curcumin in C. elegans is related to the mitogen-activated protein kinase (MAPK) pathway. qRT-PCR results confirmed that the expression of oxidative stress-related genes (sod-1, sod-2, sod-3, gst-4) was increased, and the expression of MAPK signaling pathway-related genes (sek-1, pmk-1, nsy-1) was significantly downregulated. Furthermore, the administration of curcumin extended the lifespan of nematodes, potentially through the enhancement of oxidative stress resistance and the downregulation of the MAPK signaling pathway. These findings improve our understanding of both lifespan extension and the potential mechanism of curcumin in C. elegans. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests health benefits of ketone bodies, and especially for longevity. However, the precise role of endogenous ketogenesis in mammalian life span, and the safety and efficacy of the long‐term exogenous supplementation of ketone bodies remain unclear. In the present study, we show that a deficiency in endogenous ketogenesis, induced by whole‐body Hmgcs2 deletion, shortens life span in mice, and that this is prevented by daily ketone body supplementation using a diet containing 1,3‐butanediol, a precursor of β‐hydroxybutyrate. Furthermore, feeding the 1,3‐butanediol‐containing diet from early in life increases midlife mortality in normal mice, but in aged mice it extends life span and prevents the high mortality associated with atherosclerosis in ApoE‐deficient mice. By contrast, an ad libitum low‐carbohydrate ketogenic diet markedly increases mortality. In conclusion, endogenous ketogenesis affects mammalian survival, and ketone body supplementation may represent a double‐edged sword with respect to survival, depending on the method of administration and health status. [ABSTRACT FROM AUTHOR]

Sexual reproduction increases genetic diversity but it is also associated with costs such as exposure to parasites or reduced life span. Black soldier flies, Hermetia illucens , are a suitable model to investigate the trade-offs between reproduction and longevity as they largely rely on their larval resources and do not have to feed as adults. Here, we investigated the influence of mating status on adult longevity. We found that females had shorter longevity than males, but the intersexual difference in life span was reduced through mating which increased female but decreased male longevity. This suggests a cost of mating for males, while female longevity increased, likely via nutrients transferred by males during copulation (sensu nuptial gifts). We also investigated the transparent abdominal 'window' of adult black soldier flies, the fullness of which may be a proxy for both age and mating status. Window fullness decreased with age in unmated males whereas unmated females maintained high fullness until they were older. Additionally, mated females mostly had full windows while those of mated males were mostly empty. Our findings have not only expanded our understanding of resource allocation in this species, but they also harbour great potential for applicability in the industrial sector given the extensive use of black soldier flies in organic waste management. • Unmated male black soldier flies live longer than unmated females. • Mating reduces the longevity difference between unmated males and females. • The transparent abdominal 'window' of black soldier flies can be a proxy for age. • The relationship between 'window' fullness and age differs between the sexes. • Male black soldier flies may be choosing females with full 'windows' for mating. [ABSTRACT FROM AUTHOR]

Introduction: In the last decade researchers have attempted to investigate the shared genetic architecture of longevity and age-related diseases and assess whether the increased longevity in certain people is due to protective alleles in the risk genes for a particular condition or whether there are specific "longevity" genes increasing the lifespan independently of age-related conditions' risk genes. The aim of this study was to investigate the shared genetic component between longevity and two age-related conditions. Methods: We performed a cross-trait meta-analysis of publicly available genome-wide data for Alzheimer's disease, coronary artery disease and longevity using a subset-based approach provided by the R package ASSET. Results: Despite the lack of strong genetic correlation between longevity and the two diseases, we identified 38 genome-wide significant lead SNPs across 22 independent genomic loci. Of them 6 were found to be potentially shared among the three traits mapping to genes including DAB2IP, DNM2, FCHO1, CLPTM1, and SNRPD2. We also identified 19 novel genome-wide associations for the individual traits in this study. Functional annotations and biological pathway enrichment analyses suggested that pleiotropic variants are involved in clathrin-mediated endocytosis and plasma lipoprotein and neurotransmitter clearance processes. Discussion: In summary, we have been able to advance in the knowledge of the genetic overlap existing among longevity and the two most common age-related disorders. [ABSTRACT FROM AUTHOR]

The mechanistic target of rapamycin (mTOR) kinase is one of the top drug targets for promoting health and lifespan extension. Besides rapamycin, only a few other mTOR inhibitors have been developed and shown to be capable of slowing aging. We used machine learning to predict novel small molecules targeting mTOR. We selected one small molecule, TKA001, based on in silico predictions of a high on-target probability, low toxicity, favorable physicochemical properties, and preferable ADMET profile. We modeled TKA001 binding in silico by molecular docking and molecular dynamics. TKA001 potently inhibits both TOR complex 1 and 2 signaling in vitro. Furthermore, TKA001 inhibits human cancer cell proliferation in vitro and extends the lifespan of Caenorhabditis elegans, suggesting that TKA001 is able to slow aging in vivo. [ABSTRACT FROM AUTHOR]

Post-metamorphic body growth and longevity of two archaic terrestrial frogs (Anura: Leiopelmatidae) endemic to New Zealand are described using data from long-term capture-recapture studies and measurements of snout-vent length. Population studies of Hamilton's frog (Leiopelma hamiltoni) on Te Pākeka/Maud Island, Marlborough Sounds, have been undertaken since 1976 and Archey's frog (L. archeyi) in the Coromandel Ranges since 1982. The expectation-maximisation algorithm was used to fit von Bertalanffy growth curves to the data, providing maximum-likelihood estimation of parameters associated with frog growth. New Zealand endemic frogs take at least 4-7 years to reach breeding maturity in the wild and have maximum life spans of at least 39 years in L. archeyi and 45 years in L. hamiltoni. Amongst a small sample of 26 Hochstetter's frogs (L. hochstetteri) at the Coromandel site, the oldest individual was at least 18 years old. [ABSTRACT FROM AUTHOR]

Melittobia acasta Walker is one among other hymenopterous parasitoids of Megachile rotundata F. Commercial M. rotundata populations are employed to pollinate North American alfalfa for seed production. This wasp can be prolific when using M. rotundata as a host and can reduce or destroy bee stocks. Hundreds of M. acasta female offspring can develop in a single M. rotundata cell and disperse to infest other cells, producing thousands of more parasitoids. In this study, we determined (i) upon what bee life stages M. acasta females choose to lay eggs and if those eggs ultimately become adults and (ii) M. acasta female longevity when exposed to various resources within M. rotundata cells. We found that M. acasta females lay eggs on M. rotundata prepupae and pupae and that those eggs can hatch and survive to adulthood. Eggs are not laid on early instar bee larvae; eggs laid on adults do not survive. Average female life span is 5 days without feeding, 8–9 days if a pollen–nectar provision is available while the bee develops through larval stages, and 34 days if the wasp can feed on prepupal hemolymph. Wasp females can emerge from bee cells several days after trays of cells are taken to fields. Therefore, adult females could survive long enough for new bee offspring to become prepupae. Our findings support a better understanding of host life stage preference and the longevity of M. acasta females that can inform the timing of the implementation of possible control measures. [ABSTRACT FROM AUTHOR]

Nowadays, when a life span of sensor nodes are threatened by the shortage of energy available for communication, sink mobility is an excellent technique for increasing its lifespan. When communicating via a WSN, the use of nodes as a transmission method eliminates the need for a physical medium. Sink mobility in a dynamic network topology presents a problem for sensor nodes that have reserved resources. Unless the route is revised and changed to reflect the location of the mobile sink location, it will be inefficient for delivering data effectively. In the clustering strategy, nodes are grouped together to improve communication, and the cluster head receives data from compactable nodes. The sink receives the aggregated data from the head. The cluster head is the central node in the conventional technique. A single node uses more energy than a node that is routed to a dead node. Increasing the number of people using a route shortens its lifespan. The proposed work demonstrates the effectiveness with which sensor node paths can be modified at a lower cost by utilising the virtual grid. The best routes are maintained mostly by sink node communication on routes based on dynamic route adjustment (VGDRA). Only specific nodes are acquired to re-align data supply to the mobile sink in accordance with new paradigms of route reconstruction. According to the results, VGDRA schemes have a longer life span because of the reduced number of loops. [ABSTRACT FROM AUTHOR]

Diverse mouse strains have different health and life spans, mimicking the diversity among humans. To capture conserved aging signatures, we studied long‐lived C57BL/6J and short‐lived NZO/HILtJ mouse strains by profiling transcriptomes and epigenomes of immune cells from peripheral blood and the spleen from young and old mice. Transcriptional activation of the AP‐1 transcription factor complex, particularly Fos, Junb, and Jun genes, was the most significant and conserved aging signature across tissues and strains. ATAC‐seq data analyses showed that the chromatin around these genes was more accessible with age and there were significantly more binding sites for these TFs with age across all studied tissues, targeting pro‐inflammatory molecules including Il6. Age‐related increases in binding sites of JUN and FOS factors were also conserved in human peripheral blood ATAC‐seq data. Single‐cell RNA‐seq data from the mouse aging cell atlas Tabula Muris Senis showed that the expression of these genes increased with age in B, T, NK cells, and macrophages, with macrophages from old mice expressing these molecules more abundantly than other cells. Functional data showed that upon myeloid cell activation via poly(I:C), the levels of JUN protein and its binding activity increased more significantly in spleen cells from old compared to young mice. In addition, upon activation, old cells produced more IL6 compared to young cells. In sum, we showed that the aging‐related transcriptional activation of Jun and Fos family members in AP‐1 complex is conserved across immune tissues and long‐ and short‐living mouse strains, possibly contributing to increased inflammation with age. [ABSTRACT FROM AUTHOR]

The Rasayana is one of the 8 specialized branches of Ayurveda that primarily deals with the maintenance of health. Drosophila melanogaster is an excellent organism to test Ayurvedic medicines. Longevity effect of Rasayana drugs can be well understood by Drosophila melanogaster as it has a shorter life span, easy to handle, easy to culture and no ethical clearance is required. The fruit fly or Drosophila is one of the most intensively studied in medicine and serves as a model system for investigations of many developmental and cellular processes common to higher eukaryotes, including man. This fly is being used for genetic studies since almost a century. Studies on Drosophila have enabled biologists to make significant contributions to the fields as diverse as basic genetics, population biology, evolutionary biology, behavioral biology and molecular biology. It has a short life cycle, easy and inexpensive in culturing and they could be kept in large numbers. [ABSTRACT FROM AUTHOR]

Although individual estimates of life expectancy are readily available, analogous couple-based estimates are not. The dearth of such estimates can be detrimental for couples undertaking important decisions together, such as retirement, savings, and other later-life considerations. Moreover, relying on available individual measures can be misleading because it results in overestimating the number of years the couple should expect to live together (joint life expectancy) and underestimating the number of years the widowed spouse expects to live (survivor life expectancy). In this article, we use data from the Longitudinal Administrative Database to provide benchmark estimates for joint and survivor life expectancy for Canadian couples and show how these estimates vary with the income and employment status of couples approaching retirement. [ABSTRACT FROM AUTHOR]

The article presents a study which explores that how convergent genomics of longevity in rockfishes highlights the genetics of human life span variation. It mentions that study reveal a common network of genes under convergent evolution, encompassing established aging regulators such as insulin signaling, yet also identify flavonoid (aryl-hydrocarbon) metabolism as a pathway modulating longevity.

The actin cytoskeleton is a three‐dimensional scaffold of proteins that is a regulatory, energyconsuming network with dynamic properties to shape the structure and function of the cell. Proper actin function is required for many cellular pathways, including cell division, autophagy, chaperone function, endocytosis, and exocytosis. Deterioration of these processes manifests during aging and exposure to stress, which is in part due to the breakdown of the actin cytoskeleton. However, the regulatory mechanisms involved in preservation of cytoskeletal form and function are not well‐understood. Here, we performed a multipronged, cross‐organismal screen combining a whole‐genome CRISPR‐Cas9 screen in human fibroblasts with in vivo Caenorhabditis elegans synthetic lethality screening. We identified the bromodomain protein, BET‐1, as a key regulator of actin function and longevity. Overexpression of bet‐1 preserves actin function at late age and promotes life span and healthspan in C. elegans. These beneficial effects are mediated through actin preservation by the transcriptional regulator function of BET‐1. Together, our discovery assigns a key role for BET‐1 in cytoskeletal health, highlighting regulatory cellular networks promoting cytoskeletal homeostasis. [ABSTRACT FROM AUTHOR]

Growth in most spring ephemerals is decreased under warmer temperatures. Although photosynthetic activities are improved at warmer temperatures, leaves senesce earlier, which prevents the bulb from reaching a larger size. A longer leaf life duration during a warm spring, therefore, may improve bulb mass. We tested this hypothesis by modulating leaf life span of Erythronium americanum through the application of Promalin® (PRO; cytokinins and gibberellins) that prolonged or silver thiosulfate (STS) that reduced leaf duration. Gas exchange and chlorophyll fluorescence were measured along with leaf and bulb carbohydrate concentrations. Plants were also pulse labelled with 13CO2 to monitor sugar transport to the bulb. Lower photosynthetic rates and shorter leaf life span of STS plants reduced the amount of carbon that they assimilated during the season, resulting in a smaller bulb compared with control plants. PRO plants maintained their photosynthetic rates for a longer period than control plants, yet final bulb biomass did not differ between them. We conclude that seasonal growth for E. americanum is not limited by leaf life duration under warm growing conditions, but rather by limited sink growth capacity. Under global warming, spring geophytes might be at risk of being reduced in size and, eventually, reproducing less frequently. [ABSTRACT FROM AUTHOR]

The influence of three seasons namely pre - kharif (Feb-May), kharif (May-Aug) and postkharif (Aug-Nov) on the biology of jassid on okra under natural climatic conditions revealed that the developmental periods showed differences over seasons. The total nymphal period was longest in postkharif (8.90±0.91days) followed pre-kharif (7.15±0.75 days) and the shortest during kharif (6.60±0.52 days). The longest total life span was observed in post-kharif (38.29±2.79) followed by pre-kharif (34.90±1.47 days) and shortest during kharif (33.75±1.89 days). Maximum eggs was laid in post-kharif (18.70±2.45 eggs/female), followed by the pre-kharif (17.20±1.62 eggs/female) and least in kharif (16.20±1.55 eggs/female). [ABSTRACT FROM AUTHOR]

To identify new factors that promote longevity and healthy aging, we studied Drosophila CG13397, an ortholog of the human NAGLU gene, a lysosomal enzyme overexpressed in centenarians. We found that the overexpression of CG13397 (dNAGLU) ubiquitously, or tissue specifically, in the nervous system or fat body could extend fly life span. It also extended the life span of flies overexpressing human Aβ42, in a Drosophila Alzheimer's disease (AD) model. To investigate whether dNAGLU could influence health span, we analyzed the effect of its overexpression on AD flies and found that it improved the climbing ability and stress resistance, including desiccation and hunger, suggesting that dNAGLU improved fly health span. We found that the deposition of Aβ42 in the mushroom body, which is the fly central nervous system, was reduced, and the lysosomal activity in the intestine was increased in dNAGLU over-expressing flies. When NAGLU was overexpressed in human U251-APP cells, which expresses a mutant form of the Aβ-precursor protein (APP), APP-p.M671L, these cells exhibited stronger lysosomal activity and and enhanced expression of lysosomal pathway genes. The concentration of Aβ42 in the cell supernatant was reduced, and the growth arrest caused by APP expression was reversed, suggesting that NAGLU could play a wider role beyond its catalytic activity to enhance lysosomal activity. These results also suggest that NAGLU overexpression could be explored to promote healthy aging and to prevent the onset of neurodegenerative diseases, including AD. [ABSTRACT FROM AUTHOR]

The spatio-temporal regulation of gene expression determines the fate and function of various cells and tissues and, as a consequence, the correct development and functioning of complex organisms. Certain mechanisms of gene activity regulation provide adequate cell responses to changes in environmental factors. Aside from gene expression disorders that lead to various pathologies, alterations of expression of particular genes were shown to significantly decrease or increase the lifespan in a wide range of organisms from yeast to human. Drosophila fruit fly is an ideal model system to explore mechanisms of longevity and aging due to low cost, easy handling and maintenance, large number of progeny per adult, short life cycle and lifespan, relatively low number of paralogous genes, high evolutionary conservation of epigenetic mechanisms and signalling pathways, and availability of a wide range of tools to modulate gene expression in vivo. Here, we focus on the organization of the evolutionarily conserved signaling pathways whose components significantly influence the aging process and on the interconnections of these pathways with gene expression regulation. [ABSTRACT FROM AUTHOR]

Histone methylation plays crucial roles in the development, gene regulation, and maintenance of stem cell pluripotency in mammals. Recent work shows that histone methylation is associated with aging, yet the underlying mechanism remains unclear. In this work, we identified a class of putative histone 3 lysine 9 mono/dimethyltransferase genes (met-2, set-6, set-19, set-20, set-21, set-32, and set-33), mutations in which induce synergistic lifespan extension in the long-lived DAF-2 (insulin growth factor 1 [IGF-1] receptor) mutant in Caenorhabditis elegans. These putative histone methyltransferase plus daf-2 double mutants not only exhibited an average lifespan nearly three times that of wild-type animals and a maximal lifespan of approximately 100 days, but also significantly increased resistance to oxidative and heat stress. Synergistic lifespan extension depends on the transcription factor DAF-16 (FOXO). mRNA-seq experiments revealed that the mRNA levels of DAF-16 Class I genes, which are activated by DAF-16, were further elevated in the daf-2; set double mutants. Among these genes, tts-1, F35E8.7, ins-35, nhr-62, sod-3, asm-2, and Y39G8B.7 are required for the lifespan extension of the daf-2; set-21 double mutant. In addition, treating daf-2 animals with the H3K9me1/2 methyltransferase G9a inhibitor also extends lifespan and increases stress resistance. Therefore, investigation of DAF-2 and H3K9me1/2 deficiency-mediated synergistic longevity will contribute to a better understanding of the molecular mechanisms of aging and therapeutic applications. [ABSTRACT FROM AUTHOR]

The study of healthy human aging is important for shedding light on the molecular mechanisms behind aging to promote well‐being and to possibly predict and/or avoid the development of age‐related disorders such as atherosclerosis and diabetes. Herein, we have employed an untargeted mass spectrometry‐based approach to study age‐related protein changes in a healthy Sicilian plasma cohort including long‐lived individuals. This approach confirmed some of the previously known proteins correlated with age including fibulin‐1, dystroglycan, and gamma‐glutamyl hydrolase. Furthermore, our findings include novel proteins that correlate with age and/or with location and uric acid, which could represent a unique signature for healthy aging. [ABSTRACT FROM AUTHOR]

In most organisms, reproduction is correlated with shorter life span. However, the reproductive queen in eusocial insects exhibits a much longer life span than that of workers. In Harpegnathos ants, when the queen dies, workers can undergo an adult caste switch to reproductive pseudo-queens (gamergates), exhibiting a five-times prolonged life span. To explore the relation between reproduction and longevity, we compared gene expression during caste switching. Insulin expression is increased in the gamergate brain that correlates with increased lipid synthesis and production of vitellogenin in the fat body, both transported to the egg. This results from activation of the mitogen-activated protein kinase (MAPK) branch of the insulin signaling pathway. By contrast, the production in the gamergate developing ovary of anti-insulin Imp-L2 leads to decreased signaling of the AKT/forkhead box O (FOXO) branch in the fat body, which is consistent with their extended longevity. [ABSTRACT FROM AUTHOR]

Polyploidy is a significant component in the evolution of many taxa, particularly plant groups. However, new polyploids face substantial fitness disadvantages due to a lack of same‐cytotype mates, and the factors promoting or preventing polyploid establishment in natural populations are often unclear. We develop spatially explicit agent‐based simulation models to test the hypothesis that a perennial life history and clonal propagation facilitate the early stages of polyploid establishment and persistence. Our models show that polyploids are more likely to establish when they have longer life spans than diploids, especially when self‐fertilization rates are high. Polyploids that combine sexual and clonal reproduction can establish across a wide range of life histories, but their success is moderated by clonal strategy. By tracking individuals and mating events, we reveal that clonal architecture has a substantial impact on the spatial structure of the mixed diploid‐polyploid population during polyploid establishment: altering patterns of mating within or between cytotypes via geitonogamous self‐fertilization, the mechanisms through which polyploid establishment proceeds, and the final composition of the polyploid population. Overall, our findings provide novel insight into the role of clonal structure in modulating the complex relationship between polyploidy, perenniality, and clonality and offer testable predictions for future empirical work. [ABSTRACT FROM AUTHOR]

Background: The sex gap in life expectancy has been narrowing in Finland over the past 4-5 decades; however, on average, women still live longer than men. Epigenetic clocks are markers for biological aging which predict life span. In this study, we examined the mediating role of lifestyle factors on the association between sex and biological aging in younger and older adults.Methods: Our sample consists of younger and older twins (21‒42 years, n = 1 477; 50‒76 years, n = 763) including 151 complete younger opposite-sex twin pairs (21‒30 years). Blood-based DNA methylation was used to compute epigenetic age acceleration by 4 epigenetic clocks as a measure of biological aging. Path modeling was used to study whether the association between sex and biological aging is mediated through lifestyle-related factors, that is, education, body mass index, smoking, alcohol use, and physical activity.Results: In comparison to women, men were biologically older and, in general, they had unhealthier life habits. The effect of sex on biological aging was partly mediated by body mass index and, in older twins, by smoking. Sex was directly associated with biological aging and the association was stronger in older twins.Conclusions: Previously reported sex differences in life span are also evident in biological aging. Declining smoking prevalence among men is a plausible explanation for the narrowing of the difference in life expectancy between the sexes. Data generated by the epigenetic clocks may help in estimating the effects of lifestyle and environmental factors on aging and in predicting aging in future generations. [ABSTRACT FROM AUTHOR]

I explored the hypothesis that recruitment may stabilize the numerical dynamics of stream-dwelling salmonids by triggering density-dependent feedback loops through the operation of recruitment dependence on individual growth, mortality, life span and maximum size and their effects on fecundity. I examined 98 cohorts of two Salmo trutta populations of northern Spain and a population of Jutland (Denmark) located 2400 km apart. Recruitment, growth, mortality, life span and maximum size were inter-related, were recruitment-dependent and described negative power trajectories. In the Spanish populations, faster-growing individuals of weakly recruited cohorts with lower mortality attain longer life span and larger size. Hence, larger females spawning more abundant, larger eggs that, in turn, induce stronger cohorts of higher spawners' abundance, recruitment and mortality. The mortality patterns match the self-thinning patterns, an ultimate expression of competition. Significant relationships among self-thinning slopes and mortalities rates with increasing recruitment demonstrate that the rate at which density-driven mortality is higher, the stronger the intensity of intraspecific competition. Space-limited habitat and size-dependent resource availability underpinning site-specific carrying capacities suggest that interference competition is the primary mechanism underpinning population regulation. [ABSTRACT FROM AUTHOR]

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The Great Plains drought of 1931–1939 was a prolonged socio-ecological disaster with widespread impacts on society, economy, and health. While its immediate impacts are well documented, we know much less about the disaster's effects on distal human outcomes. In particular, the event's effects on later life mortality remain almost entirely unexplored. Closing this gap would contribute to our understanding of the long-term effects of place-based stress. To help fill this gap, I use a new, massive, linked mortality dataset to investigate whether young men's exposure to drought and dust storms in 341 Great Plains counties was linked to a higher risk of death in early-old age. Contrary to expectations, results suggest exposure to drought conditions had no obvious adverse effect among men aged 65 years or older at time of death—rather, the average age at death was slightly higher than for comparable men without exposure. This effect also appears to have been stronger among Plainsmen who stayed in place until the drought ended. A discussion of potential explanations for these counterintuitive results is provided. [ABSTRACT FROM AUTHOR]

Gas journal bearings are widely employed in high-speed spindles for the micromachining industry. Compared to their oil and rolling counterparts, gas bearings have a longer life span, lower friction and a lower level of noise. In order to design accurate high-speed spindles supported by externally pressurized gas bearings, it is vital to analyze the characteristics of rotor bearing systems. In this paper, we present an analysis of the unbalance response of a high-speed spindle supported by gas journal bearings. A number of aspects to enhance the accuracy of the system are discussed. We performed the analysis by considering a nonlinear and a linearized numerical model validated through experimental measurements. [ABSTRACT FROM AUTHOR]

Simple Summary: This paper proposes a hypothesis that the human lifespan could be extremely long and healthy if different life stages were elongated with specific strategies. If the hypothesis is tested and confirmed, biomedical research will enter a new era and the dream of long-lived human beings may be achieved in the near future. The human lifespan has been increasing but will soon reach a plateau. A new direction based on the principal law of lifespan (PLOSP) may enable the human lifespan to be extremely healthy and long by the proper manipulation of the well-defined growing stages of the lifespan. The lifespan of creatures on earth from a single cell to animals can be elongated at different life stages including prenatal development, body growth, reproductivity, and aging. Each life stage has its own specific physiological and metabolic characteristics. Each life stage can be lengthened by either slowing its processes or continuously maintaining the activities of its function. Unfortunately, the current biomedical research on the extension of lifespans has mainly focused on the aging stage. Recognizing and clearly defining the periods of transition and the boundaries of life stages are essential for achieving the goal of long-lived healthy humans based on the PLOSP. The biomedical measures and pharmacological treatments for the extension of lifespans is life-stage-specific. The PLOSP can be tested with modified studies on longevity with a variety of technologies such as castration and ovariectomy. Sex differences in biological functions and the sequential order of the life stages requires different approaches for females and males. [ABSTRACT FROM AUTHOR]