Maximum Life Research Articles

Plant traits and environment: floating leaf blade production and turnover of Nymphoides peltata (S.G. Gmel.) O. Kuntze (Menyanthaceae).

BackgroundNymphaeid macrophytes, rooting in the sediment of water bodies and characterized by floating leaves, play an important role in wetland ecosystems. The present research deals with the effects of limited space, limited nutrient availability, water temperature and an unexpected inundation on the production, turnover and plasticity of floating leaves of the globally widespread species Nymphoides peltata (Fringed waterlily).MethodsThe effects of these environmental conditions were studied in two plots in outdoor concrete tanks (CT1, CT2, mesocosms simulating occurrence in small ponds) and in two plots in the floodplain oxbow lake Bemmelse Strang (BS1, BS2). Plot CT1 was situated in a stand coexisting with helophytes, plot CT2 in a monospecific stand, plot BS1 in the center and plot BS2 at the open water border of a monospecific stand. All floating leaf blades within the plots were marked at appearance at the water surface and subsequently length, width and damage of each leaf and maximum and minimum water temperatures were measured bi-weekly. Area and biomass of leaf blades were calculated based on leaf length and width and were used to calculate turnover rates and production.ResultsThe growth period started in May and ended mid-October with continuous production of floating leaves during nearly the whole vegetation period. In the tanks the water level was very stable, but the lake underwent an inundation by river water, causing a sudden loss of existing leaves. Considering environmental conditions and based on the assumed ranking from low to high nutrient availability, the ranking of the plots was CT1, CT2, BS1, BS2. This order was found for maximum leaf life span and maximum leaf length, and the reverse order was found for number of leaves, new leaves per day and duration of the vegetation period. Turnover rates appeared to be relatively similar for plots CT1, CT2 and BS1, but for the deeper border plot BS2 lower ratios were found. These results indicate that increased enclosure with expected nutrient limitation causes (1) the production of high numbers of small leaves with larger totals for leaf area and biomass, (2) a shift towards increased sexual reproduction by the production of more flowering stem leaves.

Effect of Multi-Mode Thermosonication on the Microbial Inhibition and Quality Retention of Strawberry Clear Juice during Storage at Varied Temperatures.

Strawberry juice, which is rich in nutrients and charming flavor, is favored by consumers. To explore whether multi-mode thermosonication (MTS) can ensure the quality stability of strawberry clear juice (SCJ) during storage, the effects of microbial inhibition, enzyme activity, and physicochemical properties of SCJ pretreated by MTS were evaluated during storage at 4, 25, and 37 °C in comparison with thermal pretreatment (TP) at 90 °C for 1 min. The MTS, including dual-frequency energy-gathered ultrasound pretreatment (DEUP) and flat sweep-frequency dispersive ultrasound pretreatment (FSDUP), were conducted at 60 °C for 5 and 15 min, respectively. Results showed that the total phenols, flavonoids, anthocyanins, ascorbic acid, and DPPH free radical scavenging ability of SCJ decreased during the storage period. The control sample of SCJ was able to sage for only 7 days at 4 °C based on the microbiological quality, while the FSDUP and DEUP group extended the storage period up to 21 and 14 days, respectively. The polyphenol oxidase in SCJ pretreated by MTS did not reactivate during the storage period. The MTS remarkably (p < 0.05) reduced the color deterioration, browning degree, and nutrient degradation during the storage period. Moreover, the FSDUP group exhibited the maximum shelf life with a minimum loss of quality, demonstrating that it was the most suitable processing method for obtaining high-quality SCJ. It can be concluded that the MTS has the potential to inhibit enzymatic browning, inactivating microorganisms, preserve original quality attributes, and prolong the shelf life of SCJ.

Development of DNA methylation-based epigenetic age predictors in loblolly pine (Pinus taeda).

Biological ageing is connected to life history variation across ecological scales and informs a basic understanding of age-related declines in organismal function. Altered DNA methylation dynamics are a conserved aspect of biological ageing and have recently been modelled to predict chronological age among vertebrate species. In addition to their utility in estimating individual age, differences between chronological and predicted ages arise due to acceleration or deceleration of epigenetic ageing, and these discrepancies are linked to disease risk and multiple life history traits. Although evidence suggests that patterns of DNA methylation can describe ageing in plants, predictions with epigenetic clocks have yet to be performed. Here, we resolve the DNA methylome across CpG, CHG, and CHH-methylation contexts in the loblolly pine tree (Pinus taeda) and construct epigenetic clocks capable of predicting ages in this species within 6% of its maximum lifespan. Although patterns of CHH-methylation showed little association with age, both CpG and CHG-methylation contexts were strongly associated with ageing, largely becoming hypomethylated with age. Among age-associated loci were those in close proximity to malate dehydrogenase, NADH dehydrogenase, and 18S and 26S ribosomal RNA genes. This study reports one of the first epigenetic clocks in plants and demonstrates the universality of age-associated DNA methylation dynamics which can inform conservation and management practices, as well as our ecological and evolutionary understanding of biological ageing in plants.

Determining the Best Dressing Parameters for External Cylindrical Grinding Using MABAC Method

Multi-criteria decision making (MCDM) is a research area that entails analyzing various available options in a situation involving social sciences, medicine, engineering, and many other fields. This is due to the fact that it is used to select the best solution from a set of alternatives. The MCDM methods have been applied not only in economics, medicine, transportation, and the military, but also in mechanical processing processes to determine the best machining option. In this study, determining the best dressing mode for external grinding SKD11 tool steel using an MCDM method—the MABAC (multi-attributive border approximation area comparison) method—was introduced. The goal of this research is to find the best dressing mode for achieving the minimal surface roughness (RS), the maximum wheel life (T), and the minimal roundness (R) all at the same time. To perform this work, an experiment was carried out with six input parameters: the fine dressing depth, the fine dressing passes, the coarse dressing depth, the coarse dressing passes, the non-feeding dressing, and the dressing feed rate. In addition, the Taguchi method and an L16 orthogonal array were used to design the experiment. Furthermore, the MEREC (method based on the removal effects of criteria) and entropy methods were used to determine the weight of the criteria. The best dressing mode for external cylindrical grinding has been proposed based on the results. These findings were also confirmed by comparing them to the TOPSIS (technique for order of preference by similarity to ideal solution) and MARCOS (measurement of alternatives and ranking according to compromise solution) methods.

An aqueous extract of the brown alga Eisenia bicyclis extends lifespan in a sex-specific manner by interfering with the Tor-FoxO axis.

Food has a decisive influence on our health, to the extent where even lifespan can be directly affected by it. In the present work, we have examined the effects of an aqueous extract of the marine brown alga Eisenia bicyclis in terms of its potential to extend lifespan. For this purpose, we used the fruit fly Drosophila melanogaster as a model. The experiments showed that small amounts of Eisenia extract can extend lifespan by up to 40%. This effect is not only related to the median but also to the maximum lifespan. Interestingly, this life-extending effect is sex-specific, i.e. it occurs exclusively in females. Even under stressful nutritional conditions such as a high sugar diet, this effect is detectable. Mechanistic studies showed that this life-prolonging effect depends on a functional Tor and a functional FoxO signaling pathway. It can be concluded that components of the Eisenia extract prolong lifespan by interacting with the Tor-FoxO axis. This study may serve to stimulate further investigations, which on the one hand show such a life-prolonging effect also in other organisms and on the other hand identify the substances responsible for this effect. Finally, it may also encourage the increased use of arame as a health-promoting food supplement.

Assessment of Morphological Diversity and physico -chemical characterization of Elaegnus latifolia under different agro-ecological system in East Sikkim

The present study was conducted to investigate diversity of mallero (Elaegnus latifolia) across differentagro-ecological systems in East Sikkim and to observe variations in physico-chemical parameters of themallero fruits with variation in agro-ecological system. The study was conducted in mixed farming basedagro-ecological system, farm based agro-ecological system, forest habitat based agro-ecological system,cardamom based agro-ecological system and sikkim mandarin based agro-ecological systems. Theexperiment was laid out in Completely Randomized Design with five treatments and three replications.Studies regarding growth parameters like highest plant population (4.66) and number of fruits per tree(308.00) was found in mixed farming agro-ecological system (T1). However, the number of fruits per branch(27.00) and plant spread (4.06 m) was found maximum in farm based agro-ecological system (T2). Similarly,plant leaf area (41.93 cm2) was found maximum in forest based agro-ecological system (T3). Qualityparameters like length of fruit (4.46 cm) and juice (3.50 ml) was found maximum in mixed farm based Agroecological system (T1). The highest total acidity (8.59) and organoleptic test value (2.76) were found in farmbased agro-ecological system (T2). Similarly, maximum fruit weight (22.16 g) and maximum shelf life inroom temperature (21.66) was recorded in cardamom based agro-ecological system (T4). However, thehighest TSS (13.33) was recorded in mandarin agro-ecological system (T5) and maximum shelf life of fruitin refrigerator (41.93 days) was found in forest based agro-ecological system (T3).

Cardiac PI3K p110α attenuation delays aging and extends lifespan.

Phosphoinositide 3-kinase (PI3K) is a key component of the insulin signaling pathway that controls cellular me-tabolism and growth. Loss-of-function mutations in PI3K signaling and other downstream effectors of the insulin signaling pathway extend the lifespan of various model organisms. However, the pro-longevity effect appears to be sex-specific and young mice with reduced PI3K signaling have increased risk of cardiac disease. Hence, it remains elusive as to whether PI3K inhibition is a valid strategy to delay aging and extend healthspan in humans. We recently demonstrated that reduced PI3K activity in cardiomyocytes delays cardiac growth, causing subnormal contractility and cardiopulmonary functional capacity, as well as increased risk of mortality at young age. In stark contrast, in aged mice, experi-mental attenuation of PI3K signaling reduced the age-dependent decline in cardiac function and extended maximal lifespan, suggesting a biphasic effect of PI3K on cardiac health and survival. The cardiac anti-aging effects of reduced PI3K activity coincided with enhanced oxida-tive phosphorylation and required increased autophagic flux. In humans, explanted failing hearts showed in-creased PI3K signaling, as indicated by increased phos-phorylation of the serine/threonine-protein kinase AKT. Hence, late-life cardiac-specific targeting of PI3K might have a therapeutic potential in cardiac aging and related diseases.

Improving heat extraction performance of enhanced geothermal systems: Insights from critical fracture network parameter and multi-objective optimization method

• An integrated workflow is proposed for improving thermal recovery of hot dry rocks. • Network connectivity is a key fracture parameter in dominating thermal efficiency. • Network connectivity governs thermo-hydro-mechanical processes of fractured rocks. • Fractures with connectivity around 15–35 are better for production optimization. The generation of a highly permeable fracture network in Enhanced Geothermal Systems (EGSs) is a prerequisite to develop such geothermal reservoirs efficiently. However, it lacks a quantitative geometrical metric to evaluate what kind of fracture network is preferable for geothermal production. To address this problem, we use our previously developed high-fidelity Thermo-Hydro-Mechanical (THM) coupling model to investigate the joint influence of fracture geometry and thermal stress on the THM behaviors of EGSs. Results show that the geometrical connectivity of fracture networks plays a dominant role in determining the THM processes and the thermal performance of EGSs, in which the network connectivity integrates multiple properties of fracture networks including the fracture length, intensity, location and orientation. Satisfactory thermal performance tends to be achieved when the connectivity of fracture systems ranges from 15 to 35. We focus on such fracture networks and design an appropriate production scenario for optimizing multiple objectives (i.e. maximum EGS service life, heat extraction rate, and global thermal power). The overall heat extraction performance of EGSs under the optimum scenario gets improved by 77.7% compared with the base case. This research provides an effective workflow and feasible methods for evaluating and optimizing energy exploitation efficiency of EGSs.

A nature-inspired optimal design for a ventilated brake disc

Brake discs are critical automobile components that provide the braking effect and ultimately ensure the safety of passengers. Because of intermittent braking operations, brake discs are subjected to fluctuating loads and are provided with ventilation to facilitate cooling. The present study utilized a combination of response surface methodology parametric analysis, finite element analysis, statistical analysis, predictive modeling, and design optimization. Based on the response surface methodology design of experimental runs, ventilated brake discs were modeled considering the critical design parameters, viz., radius of center hole, thickness of inboard and outboard plate, height of vanes, and offset. Using finite element analysis, the brake discs were simulated under actual braking conditions for fatigue life cycles. Thirty-two (32) trial finite element analysis trials were performed. The obtained results were interpreted using ANOVA and an effective predictive model was established. Parametric analysis was performed using plots of response surface methodology and contours to predict the optimal parameter settings. In addition, two nature-inspired optimization techniques, the genetic algorithm and particle swarm optimization, were implemented and the optimal design parameter settings were determined for maximum fatigue life. The genetic algorithm and particle swarm optimization produced 7.67% better results than the parametric analysis, clearly demonstrating that the proposed design techniques exhibited significant performance improvement compared to widely used classical techniques.

Life-history constraints, short adult life span and reproductive strategies in coral reef gobies of the genus Trimma.

Body size influences many life-history traits, with small-bodied animals tending to have short life spans, high mortality and greater reproductive effort early in life. In this study, the authors investigated the life-history traits and reproductive strategies of three small-bodied coral reef gobies of the genus Trimma: Trimma benjamini, Trimma capostriatum and Trimma yanoi. The authors found all Trimma species studied attained a small body size of <25 mm, had a short life span of <140 days and experienced high estimated daily mortality of 3.0%-6.7%. Furthermore, the pelagic larval phase accounted for 25.3%-28.5% of the maximum life span, and maturation occurred between 74.1 and 82.1 days at 15.2-15.8 mm, leaving only 35%-43% of the total life span as a reproductively viable adult. All mature individuals had gonad structures consistent with bidirectional sex change, with bisexual gonads including both ovarian and testicular portions separated by a thin wall of connective tissue. In the female and male phases, only ovaries or testes were mature, whereas gonadal tissue of the non-active sex remained. One T. benjamini individual and one T. yanoi individual had ovarian and testicular tissue active simultaneously. The results of this study highlight the life-history challenges small CRFs face on their path to reproduction and reproductive strategies that could be beneficial in fishes with high and unpredictable mortality and short reproductive life spans.

Three Month Heterochronic Parabiosis Has a Deleterious Effect on the Lifespan of Young Animals, Without a Positive Effect for Old Animals.

Our previous study showed that an exchange of blood between heterochronic parabionts for 3 months did not rejuvenate the immune system of the old partners. Moreover, the young immune system became more aged and began to function according to the "old" principle. Does this forced aging affect all systems of the organism in this model? We checked the levels of corticosterone, testosterone, insulin-like growth factor 1 (IGF-1), insulin, and thyroxine in the blood of heterochronic parabionts, but did not find significant changes compared with age-related controls. Since numerous data support the possibility of rejuvenation of the brain, muscles, and other tissues using the model of heterochronic parabiosis, as well as opposite data, we planned to assess the overall effect of this long-term blood exchange on the rate of organism aging. We measured the life span of animals whose blood was exchanged for 3 months and then were disconnected. Median and maximum life expectancy decreased in young heterochronic parabionts compared with the isochronic control. Old heterochronic parabionts showed only a small trend toward an increase in the median life span, but it was not statistically significant, and the maximum life span did not change compared with the isochronic parabionts. These data support our assumption that old blood contains factors capable of inducing aging in young animals. The mechanism of selective suppression of aging factor production in the organism could be a key research field for life extension.

Pre-harvest application of inorganic sources of nutrient on yield and shelf life of broccoli

A study was conducted at Chanchra, Sadar Upazila, Jashore, Bangladesh during Rabi seasons of 2019-20 and 2020-21 to evaluate pre-harvest treatments of inorganic nutrient sources on yield and shelf life of broccoli through Randomized Complete Block Design (RCBD) with three replications and six treatments which were; T1= soil test based 50% NPK with blanket dose, T2=soil test based 75% NPK with blanket dose, T3= soil test based 100% NPK with blanket dose, T4=soil test based 125% NPK with blanket dose, T5=local farmers practice (N138 P75 K94 S27 Zn5 kg ha-1),T6 = control.Completely Randomized Design (CRD) was designed to determine the shelf life of broccoli with three replications considering three factors; (i) pre-harvest treatments of inorganic sources of nutrient; (ii) storage materials at room temperature and (iii) storage materials at cold storage condition.Findings revealed that the effects of different inorganic sources of nutrients significantly influenced on yield and shelf life of broccoli. The treatment T3 (soil test based 100% NPK with blanket dose) resulted in better marketable curd yield with maximum gross returns, net returns and Benefit Cost Ratio(BCR) as compared to other treatments. The treatment T1 (soil test based 50% dose of NPK with blanket dose) recorded the maximum shelf life of 6.57 daysand 6.83 days at room temperature (14-240C with RH 60-65%) and 23.65 days and 24.25 days at cold storage (40C with RH 90-95%) condition using High -Density Polyethylene (HDP;15 micron) vacuum pack during the years of 2019-20 and 2020-21 respectively. SAARC J. Agric., 20(1): 131-141 (2022)

Administration of krill oil extends lifespan of fish Nothobranchius guentheri via enhancement of antioxidant system and suppression of NF-κB pathway.

Krill oil (KO) extracted from Antarctic krill (Euphausia superba) mainly comprises phospholipids and triglycerides. KO has been shown to prolong the median lifespan of the nematode Caenorhabditis elegans, but to shorten the lifespan of long-lived F1 mice; therefore, it remains controversial over the life-extending property of KO. In this study, we clearly demonstrated that dietary intake of KO extended both the mean and maximum lifespans of aged male Nothobranchius guentheri (p < 0.05), reduced the accumulation of lipofuscin (LF) (p < 0.05) in the gills and senescence-associated β-galactosidase (SA-β-Gal) (p < 0.05) in the caudal fins, and lowered the levels of protein oxidation (p < 0.05), lipid peroxidation (p < 0.01), and reactive oxygen species (ROS) (p < 0.01) in the muscles and livers, indicating that KO possesses rejuvenation and anti-aging activity. We also showed that KO enhanced the activities of antioxidant enzymes catalase (CAT) (p < 0.05), superoxide dismutase (SOD) (p < 0.05), and glutathione peroxidase (GPX) (p < 0.05) in aged male N. guentheri. In addition, KO administration effectively reversed histological lesions including inflammatory cell infiltration and structural collapse in the muscles and livers of aged N. guentheri and suppressed the nuclear factor kappa-B (NF-κB) signaling pathway (p < 0.05), a master regulator of inflammation. Altogether, our study indicates that KO has anti-aging and rejuvenation property. It also suggests that KO exerts its anti-aging and rejuvenation effects via enhancement of the antioxidant system and suppression of the NF-κB signaling pathway.

Numerical analysis of dynamics and durability of rotor elements in gas turbine engines

In this work, an accurate algorithm for calculating the durability of rotor wheels in gas turbine engines undergoing detuning of parameters was developed. The finite element method, underlying the Ansys Software, was used for modelling free and forced oscillations of rotor wheels. During the experiments, the detuning was simulated by attaching additional masses to the wheel blades. The calculations of frequencies, modes of forced oscillations, as well as dynamic stresses arising due to these oscillations, were carried out using the Fourier series. The schematisation of dynamic stresses, i.e. differentiation of obtained stresses into levels having specific amplitudes, was used to calculate durability. The main research result comprises the developed algorithm for calculating the durability of rotor wheels of gas-turbine engines subjected to parameter detuning. This algorithm served as a basis for the Ocs_Rotor software for investigating the natural oscillations of blades and rotor wheels under parameter detuning. Using this software, the natural frequencies and oscillation modes of the blades were calculated. Dynamic stresses under forced oscillations, as well as durability of the rotor wheel, were calculated using the obtained results. The results of calculating the service life of an actual rotor wheel having three different positions of blades under detuning allowed the construction having the maximum service life of 1.75 * 105 hours to be selected. Comparing the results of calculations, obtained using the Ocs_Rotor software, with those of field experiments, carried out at Brandenburg Technical University (Cottbus, Germany), demonstrated high accuracy characterised by a maximum error of 4 %. This suggests that the software may be used to design structures of maximum service life. The results of durability calculations of an actual rotor wheel having different blade positions under detuning allowed practical recommendations for engineers on the positioning of the blades in the wheel to be established.

Osteohistology and taphonomy support social aggregation in the early ornithischian dinosaur Lesothosaurus diagnosticus

AbstractLesothosaurus diagnosticus is a small ornithischian dinosaur from the Lower Jurassic Massospondylus Assemblage Zone of the upper Elliot Formation of the Karoo Basin of South Africa and Lesotho. The Early Jurassic age, comparatively large sample size, and multiple growth stages of Lesothosaurus make it an excellent taxon for investigating the plesiomorphic condition of ornithischian growth. Here, we examine the osteohistology of an ontogenetic series of Lesothosaurus diagnosticus using multiple limb elements to assess the maximum body size, life history, growth dynamics and potential for sociality in one of the earliest‐branching ornithischian dinosaurs. We found that Lesothosaurus grew rapidly during early and mid‐ontogeny (as shown by its highly vascularized woven‐parallel complex) with its growth rate decreasing between 2–4 years of age, possibly indicating the onset of reproductive maturity. However, an external fundamental system, indicating a cessation in growth, could not be confirmed in any of the individuals studied, suggesting that at 6 years of age, this taxon was still not fully grown. The presence of multiple individuals of varying ontogenetic stages in a monodominant bone bed strongly suggests that it lived in multigenerational herds, indicating that, along with the Venezuelan Laquintasaura venezuelae, social behaviour developed very early in ornithischian evolutionary history.

Are there plenty of fish in the sea? How life history traits affect the eco-evolutionary consequences of population oscillations

Understanding fish population oscillations is important for both fundamental population biology and for fisheries science. Much research has focused on the causes of population oscillations, but the eco-evolutionary consequences of population oscillations are unclear. Here, we used an empirically parametrised individual-based simulation model to explore the consequences of oscillations with different amplitudes and wavelengths. We show that oscillations with a wavelength shorter than the maximum lifespan of the fish produce marked differences in the evolutionary trajectories of asymptotic length. Wavelengths longer than the maximum lifespan of the fish, in turn, mainly manifest as ecological effects seen as the population biomass oscillation. The evolutionary and ecological differences increase with increasing amplitude, however, the two-year wavelength causes opposing results from all the other scenarios. This is likely facilitated by the relatively stable number of fish in the population as a poor year is always counteracted by the previous good year and vice versa. Our results highlight the evolutionary signatures and following ecological consequences that natural population oscillations can cause.

Plasma lactate dehydrogenase and pyruvate kinase activity changes with body mass and age across birds and mammals

Abstract Birds and mammals produce most adenosine triphosphate (ATP) through mitochondrial oxidative phosphorylation, but when oxygen is not present in sufficient levels, ATP can be produced through anaerobic glycolysis. Pyruvate kinase (PK) catalyzes the final step of glycolysis by converting phosphoenolpyruvate and adenosine diphosphate (ADP) into pyruvate and ATP. Lactate dehydrogenase (LDH) is important for anaerobic glycolysis by catalyzing the conversion of pyruvate into lactate. In this study, we measured LDH and PK activities in plasma from birds and mammals in order to determine the relationship between LDH and PK with respect to body mass and age. Our results show that birds had a higher LDH and PK activity compared with mammals. There is a positive relationship between body mass and plasma LDH activity in birds only. However, this relationship disappears when the data are phylogenetically corrected. We did not observe a significant relationship between plasma LDH and age in birds or mammals. Plasma PK activity was negatively correlated with body mass in birds but not in mammals and positively associated with age in both birds and mammals. The relationship between LDH and PK with respect to body mass and age may be complex due to differences in metabolism in birds and mammals. Increases in LDH and PK activity with body mass in birds may be linked to anaerobic demands of flight, especially in larger birds. A decrease in LDH activity with age/MLSP (maximum lifespan) in mammals may reflect a differing metabolic shift as compared with birds. Increases in PK with age in both mammals and birds may help them cope with greater energetic needs as cells age.

Sustainability-based reliability design for reuse of concrete components

Imminent crisis of climate change makes it imperative to strengthen efforts on adaptation and mitigation of destructive environmental impacts due to concrete production and application. Concrete component reuse in urban renewal will be an effective means to reduce concrete and steel production demands, whereas the conventional structural design encounters difficulties to ensure the reliability of reused components. In this work, we propose a novel paradigm for sustainability-based reliability design for the reuse of concrete components (abbreviated to sustainability-based reuse design paradigm), and a domain-specific machine learning approach is adopted to identify the reusability of concrete components and evaluate possible risks under the uncertain environment due to climate change, on the basis of the carbonation-induced degradation pattern and in-situ structure and climate data collected. The proposed paradigm has been implemented and validated in a case study of reused concrete structure design in Guangzhou area. Our results have shown that the proposed sustainability-based reuse design paradigm improves the design credibility, while the conventional design, which ignores climate change, underestimates failure probabilities grossly and overestimates the component’s maximum service life by up to 22.5 years. By dispelling the reliability concerns on concrete component reuse, the sustainability-based reuse design paradigm will boost its promotion and unleash its substantial potential for carbon emission reduction.

MEDB-12. Severe developmental abnormalities and proliferative cerebellar lesions induced by combined activity of Wnt signalling and loss of SMARCA4

Almost all medulloblastomas (MB) of the WNT subgroup are characterized by hotspot mutations in CTNNB1, and mouse models have convincingly demonstrated the tumor-initiating role of these mutations as well as the tumor origin in the dorsal brain stem. Around 20 % of WNT MB additionally carry SMARCA4mutations, but the functional role of these alterations is mostly unknown. We therefore amended previously described Blbp-cre::Ctnnb1(ex3)Fl/+mice by the introduction of a floxed Smarca4 allele. In contrast to existing literature, Blbp-cre::Ctnnb1(ex3)Fl/+ mice had a maximum life span of only 17 days, even after breeding into two different genetic backgrounds (C57BL/6J and 129S2/Sv). The mice displayed a severe developmental phenotype including a thinned cerebral cortex, hydrocephalus, missing cerebellar foliation and layering as well as non-proliferative cell accumulations in brain stem and cerebellum. An additional homozygous loss of SMARCA4 even resulted in prenatal death for most mice and caused big proliferative lesions in the cerebellum at embryonal day 14.5. These lesions appear to originate from SOX2-positive progenitor cells in the cerebellar ventricular zone. In a next experiment, cells isolated from this region will be characterized in vitro and will be transplanted orthotopically to evaluate their neoplastic potential in vivo. Altogether, we hope to elucidate how a loss of SMARCA4 and mutations of Ctnnb1 cooperate during hindbrain development and tumor formation within this region.

Longevity secret: A pluripotent superpower

Mammalian lifespans are dramatically diverse. Identifying the molecular signatures and underlying mechanism of longevity is of keen interest. Using comparative transcriptomics, Lu etal. (2022) showed that genes associated with maximum lifespan are regulated by circadian and pluripotency networks, which shed light on natural strategies for controlling lifespan.