1,159 results on '"TRADEOFF"'
Search Results
2. Life History Differences Between Lepidoptera Larvae and Blattodea Nymphs Lead to Different Energy Allocation Strategies and Cellular Qualities.
- Author
-
Taheri, Fahimeh and Hou, Chen
- Subjects
- *
LIFE history theory , *LEPIDOPTERA , *BIOMASS , *CATERPILLARS , *WEIGHT loss - Abstract
Simple Summary: Lepidoptera species have higher growth rates than Blattodea species. The different growth rates lead to different strategies to allocate energy to biosynthesis and somatic maintenance under free-feeding and low-food-availability conditions. Moreover, Lepidoptera and Blattodea spend sharply different amounts of energy on synthesizing one unit of bio-tissue, which, in turn, leads to different cellular qualities and abilities to resist stress, and may have effect on their adult lifespan. Based on this evidence, we postulate that the capability of maintaining homeostasis not only depends on the amount of energy allocated to maintenance, but also depends on the quality of the tissue, and that the tissue quality is at least partially due to the energetic investments in biosynthesis. In short, materials that are cheap to synthesize deteriorate faster, and allocating more energy to biosynthesis enhances somatic maintenance. Different life histories result in different strategies to allocate energy in biosynthesis, including growth and reproduction, and somatic maintenance. One of the most notable life history differences between Lepidoptera and Blattodea species is that the former grow much faster than the latter, and during metamorphosis, a large amount of tissue in Lepidoptera species disintegrates. In this review, using Lepidoptera caterpillars and cockroach nymphs as examples, we show that, due to these differences in growth processes, cockroach nymphs spend 20 times more energy on synthesizing one unit of biomass (indirect cost of growth) than butterfly caterpillars. Because of the low indirect cost of growth in caterpillars, the fraction of metabolic energy allocated to growth is six times lower, and that for maintenance is seven times higher in caterpillars, compared to cockroach nymphs, despite caterpillar's higher growth rates. Moreover, due to the higher biosynthetic energy cost in cockroach nymphs, they have better cellular qualities, including higher proteasomal activity for protein quality control and higher resistance to oxidative stress. We also show that under food restriction conditions, the fraction of assimilated energy allocated to growth was reduced by 120% in cockroach nymphs, as they lost body weight under food restriction, while this reduction was only 14% in hornworms, and the body mass increased at a lower rate. Finaly, we discuss future research, especially the difference in adult lifespans associated with the energetic differences. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Counting the costs of expensive tissues: mating system, brain size, and IGF-1 affect the ecological costs of transport in mammals.
- Author
-
Husak, Jerry F., Sorlin, Mahaut V., and Lailvaux, Simon P.
- Subjects
SIZE of brain ,LIFE history theory ,SEXUAL selection ,PATH analysis (Statistics) ,BODY size - Abstract
Although sexual selection can be a powerful evolutionary force in shaping the phenotype, sexually selected traits do not evolve in isolation of other traits or without influence from other selective pressures. Expensive tissues, such as brains, can constrain the evolution of sexually selected traits, such as testes, as can other energetically expensive processes, like the costs of locomotion. However, simple linear or binary analyses of specific traits of interest can prevent detection of important links within the integrated phenotype and obfuscate the importance of multiple selective forces. We used phylogenetically informed path analysis to determine causal links among mating system type, pace of life history, costs of locomotion, brain size, and testis size across 48 mammal species that exhibit a wide range of body sizes, life-history strategies, and types of locomotion. We found species with non-monogamous mating systems were associated with larger testes, faster life histories, and lower costs of locomotion compared to monogamous species. Having a larger brain was associated with a slower life history and, surprisingly, larger testes. In addition to highlighting the non-intuitive nature of certain causal relationships, our results also emphasize the utility of including multiple traits in studies of sexually selected traits, as well as considering the constraints imposed by linked traits and selection on those linked traits. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
4. The Big Tradeoff averted: five avenues to promote efficiency and equality simultaneously.
- Author
-
Zeytoon-Nejad, Ali
- Subjects
INCOME inequality ,DOUBLE standard ,ECONOMIC models ,ECONOMIC policy ,FREE enterprise - Abstract
Society as a whole faces a host of economic tradeoffs, many of which emerge around economic policies. An example of tradeoffs that any society faces in many economic realms is the tradeoff between economic efficiency and income equality (aka the efficiency-equality tradeoff). This tradeoff has been called "the Big Tradeoff" by the esteemed economist Arthur Okun, who also termed it "the Double Standard of a Capitalist Democracy." Although the efficiency-equality tradeoff is more or less an inevitable tradeoff in most societal settings and economic contexts, there are still some special circumstances in which this tradeoff can be avoided. This paper identifies five such avenues and elaborates on why and how the tradeoff between these two somewhat contradictory societal goals—efficiency and equality—can be deftly averted under the mentioned circumstances. These avenues with their transformative potential can and should be used so that a capitalist society as an integrated whole can promote both efficiency and equality at the same time under these scenarios and avoid facing the Big Tradeoff in cases where it is evitable. Static and dynamic economic models are developed, solved, and applied to facilitate the articulation and exposition of the main points of each solution with formal rigor and logical coherence. Finally, policy implications are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
5. Relationship between walking movement and reproductive traits in the red flour beetle Tribolium castaneum.
- Author
-
Matsumura, Kentarou
- Subjects
- *
RED flour beetle , *TRIBOLIUM , *ANIMAL mechanics , *BEHAVIOR genetics , *INSECT ecology - Abstract
Many animal species have movement abilities. Behavior is important for evolutionary ecology because animal movement leads to dispersal, migration, search for food and mates, and escaping from enemies. However, individual differences in movement activity are found within a population. This phenomenon can be affected by various factors, one of which is suggesting that higher moving activity has fitness cost, whereas lower moving activity has benefits. Animal movement may also affect reproduction (e.g., resource allocation tradeoff between movement and reproduction as well as intra‐ and intersexual selection). Although many previous studies have investigated the relationship between movement and reproduction, less attention has been paid to walking movement. In this study, previous studies that investigated the relationship between movement and reproduction were reviewed using the flour beetle Tribolium castaneum, a model insect in behavioral ecology and genetics. Several previous studies suggest that beetle walking is strongly associated with male and female reproductive traits. In recent years, empirical studies on the correlation between walking and other traits have increased, particularly in T. castaneum. Although this species can fly and walk, the movement is often discussed without discriminating between flight and walk. Differences in modes of movement may affect the correlation between movement and other traits; thus, discussing each mode of movement separately is necessary. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. Understanding dairy farmers' trade‐offs between environmental, social and economic sustainability attributes in feeding systems: The role of farmers' identities.
- Author
-
Oyinbo, Oyakhilomen and Hansson, Helena
- Subjects
- *
SUSTAINABLE development , *GREENHOUSE gases , *SUSTAINABILITY , *DAIRY farmers , *DAIRY farms - Abstract
There is scope for improving the sustainability of intensive dairy farms through the uptake of sustainable production practices such as more grass‐based feeding systems. Such feeding systems can reduce feed‐food competition and the environmental impacts of feed production, among other farm‐level and societal benefits. However, empirical research on how farmers' feed choices mis(align) with sustainability transitions and the associated drivers is limited. This paper explores the trade‐offs that farmers make between the environmental, social and economic sustainability impacts of grass‐based feeding systems based on data from Swedish dairy farmers. Using an identity‐based utility framework and a hybrid latent class model, we find substantial heterogeneity in dairy farmers' trade‐offs between feed‐related sustainability attributes: greenhouse gas emissions, biodiversity, animal welfare, feed self‐sufficiency, feed cost and milk yield. Furthermore, our findings demonstrate that farmers who are strongly interested in the environmental and social sustainability impacts of their dairy feeding systems, beyond economic gains, are motivated mainly by their pro‐environmental and pro‐social identities. Overall, our findings imply that identity‐enhancing interventions are promising policy instruments for encouraging the uptake of more grass‐based feeding systems. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
7. Sociality modulates nutritional carrying capacity of an endangered species.
- Author
-
Rankins, Seth T., Stephenson, Thomas R., Monteith, Kevin L., Leu, Stephan T., and Lozano, Jorge
- Subjects
PREDATION ,ENDANGERED species ,UNGULATES ,BIGHORN sheep ,BIOMASS - Abstract
Group living has well-known costs and benefits. Large groups may experience greater competition for resources, while simultaneously benefit from reduced risk through predator dilution. When there is a tradeoff between forage acquisition and predation risk, the ability to congregate into large groups may unlock access to previously unavailable habitat with high risk of predation, thereby increasing forage available to the population. We evaluated whether forage availability increased with population size and how it was mediated through changes in group size. There was a tradeoff between forage availability and predation risk. Larger groups used areas with more forage biomass and greater predation risk than smaller groups. Group size also increased with population abundance, meaning bighorn sheep used gentler terrain and areas with more forage biomass at greater population abundance. Group size functionally increased carrying capacity by yielding access to more resources for growing populations of gregarious ungulates. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
8. Sustainable Manufacturing Excellence: A Study of MSMEs’ Operational Capabilities in Jammu & Kashmir’s Geo-Political Environment
- Author
-
Bhat, Firdoos Afzal and Parvez, Saad
- Published
- 2024
- Full Text
- View/download PDF
9. How does rapid body color change affect the conspicuity of lizards to their predators and conspecifics?
- Author
-
Rojo, Andrés and Swierk, Lindsey
- Subjects
PREDATION ,ANOLES ,IMAGE analysis ,ECOLOGICAL niche ,WATER use - Abstract
Predator–prey interactions drive the evolution of prey visual camouflage, but prey species also must remain conspicuous to their conspecifics for social signaling purposes. Whether rapid body color change can help to balance conspecific visibility and predator concealment, in the eyes of each group's respective visual systems, remains poorly understood. We tested this question using water anoles (Anolis aquaticus), a small lizard that uses rapid dark-to-light body color change to visually camouflage itself from its avian predators across diverse microhabitats. We used digital image analysis and visual modeling to assess the effectiveness of color-matching camouflage in dark- and light-phase A. aquaticus, as perceived by anoles and avian predators. Our findings reveal that A. aquaticus body coloration was perceived similarly by both groups. However, sex-specific differences in overall conspicuousness emerged, with males more consistently color matching their microhabitats compared to females. Females were less likely to color match their backgrounds in their lighter phase, suggesting a sex difference in preferred conspicuity in more exposed habitats. We highlight the context-dependence of color change, with sex-specific differences and microhabitat potentially affecting its function. Significance statement: Predator and prey visual systems influence prey species' visual camouflage evolution, but whether rapid body color changes allow animals to dynamically balance conspecific visibility with predator concealment is not well known. We used visual modeling techniques to examine if water anoles (Anolis aquaticus), small lizards that employ rapid body color changes to evade their avian predators, appear differently to their predators and conspecifics depending on color phase. Our findings reveal that A. aquaticus body coloration is perceived similarly by both groups. However, we observed sex-specific differences: males and larger individuals displayed more consistent color matching across different microhabitats, whereas females showed reduced matching in their lighter phase. Our study underscores the context-dependence of the function of color change in relation to factors including sex and microhabitat. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. Reinforcement Learning for Fuel Efficient Driving on Hilly Terrain - Maximizing Horizontal Distance Travelled.
- Author
-
Anudheer, Parimi, Padakanti, Ved Krishna, and Mohamed, Sheena
- Subjects
REINFORCEMENT learning ,ARTIFICIAL intelligence ,ENERGY consumption ,BURNUP (Nuclear chemistry) ,MACHINE learning ,MOUNTAINEERING - Abstract
Reinforcement learning is a crucial technical achievement in the present era, playing a key role in generating substantial progress in artificial intelligence and machine learning applications across several areas. The application of this dynamic methodology empowers machines and software agents to independently acquire knowledge and enhance their performance through their interactions with their surroundings, hence improving problemsolving and decision-making activities. This study delves into the application of reinforcement learning techniques to train an autonomous agent within a customized Mountain Car climbing environment. The primary objective revolves around optimizing fuel usage to propel the car uphill, strategically balancing the need for ascent against the subsequent horizontal distance covered during the descent. The constrained resource, finite fuel, necessitates the agent's adaptation through a training process to discern an optimal fuel consumption strategy. The research underscores the iterative nature of this training process, wherein the agent learns to navigate the trade-off between fuel utilization and distance traveled. In essence, this investigation contributes to the realm of reinforcement learning by elucidating the agent's capacity to make informed decisions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
11. The balance of utility, privacy, and trust in network services.
- Author
-
Wan, Yi
- Subjects
- *
TRUST , *PRIVACY , *QUALITY of service , *INFORMATION theory , *ENTROPY (Information theory) , *STATISTICS - Abstract
In network services, there are often conflicts among privacy protection, trust, and service quality, which greatly reduces the regulatory effectiveness of networks. Using the basic method of information theory, this paper considers the optimization mechanism of trust and the balance between privacy and service utility from the perspective of quantifying information flow. First, we build a trust model based on multiple factors, such as direct trust, service trust, and trust cloud network. The weight of trust factors is determined by category diversity and information entropy theory. Second, based on statistical knowledge and information entropy, we propose a new privacy measurement model with hierarchical weights. Third, we establish a trust privacy service relationship model to realize the trade-off between privacy, service, and trust in networks. The demander can choose to establish trust, protect privacy, or obtain high-quality services according to personal preferences and needs. Fourth, we propose a privacy trust mapping relationship model and a privacy disclosure selection model. Finally, we design different experimental schemes. These simulation results show that our research can not only provide better quality of service but also better protect privacy and help interactive parties in networks establish a strong trust relationship. This research will improve the effectiveness of networks and can be applied to class II vaccine multi-agent collaborative supervision based on technology. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
12. A Meta-Learning Framework for Tuning Parameters of Protection Mechanisms in Trustworthy Federated Learning.
- Author
-
XIAOJIN ZHANG, YAN KANG, LIXIN FAN, KAI CHEN, and QIANG YANG
- Subjects
- *
FEDERATED learning , *TRUST , *MACHINE learning , *DATA privacy , *MEASURING instruments , *IMAGE encryption , *RANDOMIZATION (Statistics) - Abstract
Trustworthy federated learning typically leverages protection mechanisms to guarantee privacy. However, protection mechanisms inevitably introduce utility loss or efficiency reduction while protecting data privacy. Therefore, protection mechanisms and their parameters should be carefully chosen to strike an optimal tradeoff among privacy leakage, utility loss, and efficiency reduction. To this end, federated learning practitioners need tools to measure the three factors and optimize the tradeoff between them to choose the protection mechanism that is most appropriate to the application at hand. Motivated by this requirement, we propose a framework that (1) formulates trustworthy federated learning as a problem of finding a protection mechanism to optimize the tradeoff among privacy leakage, utility loss, and efficiency reduction and (2) formally defines bounded measurements of the three factors. We then propose a meta-learning algorithm to approximate this optimization problem and find optimal protection parameters for representative protection mechanisms, including randomization, homomorphic encryption, secret sharing, and compression. We further design estimation algorithms to quantify these found optimal protection parameters in a practical horizontal federated learning setting and provide a theoretical analysis of the estimation error. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
13. Microhabitat humidity rather than food availability drives thermo‐hydroregulation responses to drought in a lizard.
- Author
-
Bodineau, Théo, Chabaud, Chloé, Decencière, Beatriz, Agostini, Simon, Lourdais, Olivier, Meylan, Sandrine, and Le Galliard, Jean‐François
- Subjects
- *
VIVIPAROUS lizard , *ECOLOGICAL niche , *LIZARDS , *WATER restrictions , *ENERGY conservation , *HUMIDITY , *DROUGHTS - Abstract
The regulation of energy, water and thermal balance involves integrated processes that should drive ecological responses of ectotherms to climate change. Functional tradeoffs between thermoregulation and hydroregulation are exacerbated during hot or dry spells, but how microhabitat hydric properties and trophic resource availability influence these tradeoffs remains unknown. Here, we investigated the effects of microhabitat humidity and food availability on thermo‐hydroregulation strategies in the ground‐dwelling common lizard Zootoca vivipara during a simulated hot and dry spell event. We exposed lizards to a five‐day long acute water restriction in hot conditions in the laboratory and manipulated hydric quality of the retreat site (wet or dry shelter) as well as food availability (ad libitum food or food deprivation). Water restriction and food deprivation caused physiological responses such as muscle catabolism and mobilization of caudal energy reserves. Lizards also developed behavioural strategies to conserve water or energy via decreased thermoregulation effort, higher shelter use and increased eye closure behaviours through time. These physiological and behavioural changes were importantly buffered by the presence of a wet shelter but not by food availability. A wet retreat site reduced the behavioural conflicts between thermoregulation and hydroregulation, allowed lizards to maintain a better condition and reduced physiological dehydration. Instead, food intake did not play a major role in the regulation of hydration state and increased behavioural conflicts between thermoregulation and hydroregulation. A better consideration of thermo‐hydroregulation behaviours and microhabitat hydric quality is required to address ectotherm responses to future climate change. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
14. Investigation on Cost-Sensitivity in EEG-Based Confusion Emotion Recognition Systems via Ensemble Learning
- Author
-
Ganepola, Dasuni, Karunaratne, Indika, Maduranga, M. W. P., Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Prates, Raquel Oliveira, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Herath, Damayanthi, editor, Date, Susumu, editor, Jayasinghe, Upul, editor, Narayanan, Vijaykrishnan, editor, Ragel, Roshan, editor, and Wang, Jilong, editor
- Published
- 2024
- Full Text
- View/download PDF
15. Counting the costs of expensive tissues: mating system, brain size, and IGF-1 affect the ecological costs of transport in mammals
- Author
-
Jerry F. Husak, Mahaut V. Sorlin, and Simon P. Lailvaux
- Subjects
life history ,locomotion ,performance ,sexual selection ,tradeoff ,Biology (General) ,QH301-705.5 ,Zoology ,QL1-991 - Abstract
Although sexual selection can be a powerful evolutionary force in shaping the phenotype, sexually selected traits do not evolve in isolation of other traits or without influence from other selective pressures. Expensive tissues, such as brains, can constrain the evolution of sexually selected traits, such as testes, as can other energetically expensive processes, like the costs of locomotion. However, simple linear or binary analyses of specific traits of interest can prevent detection of important links within the integrated phenotype and obfuscate the importance of multiple selective forces. We used phylogenetically informed path analysis to determine causal links among mating system type, pace of life history, costs of locomotion, brain size, and testis size across 48 mammal species that exhibit a wide range of body sizes, life-history strategies, and types of locomotion. We found species with non-monogamous mating systems were associated with larger testes, faster life histories, and lower costs of locomotion compared to monogamous species. Having a larger brain was associated with a slower life history and, surprisingly, larger testes. In addition to highlighting the non-intuitive nature of certain causal relationships, our results also emphasize the utility of including multiple traits in studies of sexually selected traits, as well as considering the constraints imposed by linked traits and selection on those linked traits.
- Published
- 2024
- Full Text
- View/download PDF
16. CO2 pollution reduction: a tradeoff for fully fuzzy parameters in a megaproject optimization
- Author
-
Paryzad, Behzad and Eshghi, Kourosh
- Published
- 2023
- Full Text
- View/download PDF
17. Energetic cost of biosynthesis is a missing link between growth and longevity in mammals.
- Author
-
Chen Hou
- Subjects
- *
MAMMAL growth , *PHYSIOLOGY , *LIFE history theory , *BIOSYNTHESIS , *ENERGY conservation - Abstract
The comparative studies of aging have established a negative correlation between Gompertz postnatal growth constant and maximum lifespan across mammalian species, but the underlying physiological mechanism remains unclear. This study shows that the Gompertz growth constant can be decomposed into two energetic components, mass-specific metabolic rate and the energetic cost of biosynthesis, and that after controlling the former as a confounder, the negative correlation between growth constant and lifespan still exists due to a 100-fold variation in the latter, revealing that the energetic cost of biosynthesis is a link between growth and longevity in mammals. Previously, the energetic cost of biosynthesis has been thought to be a constant across species and therefore was not considered a contributor to the variation in any life history traits, such as growth and lifespan. This study employs a recently proposed model based on energy conservation to explain the physiological effect of the variation in this energetic cost on the aging process and illustrates its role in linking growth and lifespan. The conventional life history theory suggested a tradeoff between growth and somatic maintenance, but the findings in this study suggest that allocating more energy to biosynthesis may enhance the somatic maintenance and extend lifespan and, hence, reveal a more complex nature of the tradeoff. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. Hybridization constrains the evolution of mimicry complexes in woodpeckers.
- Author
-
Ottenburghs, Jente and Nicolaï, Michaël P. J.
- Subjects
- *
SPECIES hybridization , *WOODPECKERS , *SPECIES , *PROBABILITY theory , *INTROGRESSION (Genetics) - Abstract
The evolution of interspecific mimicry does not always result in perfect resemblance between mimics and models. Differences between members of a mimicry complex can be explained by genetic or developmental constraints. Alternatively, imperfect mimicry might be the outcome of a tradeoff between multiple selective pressures. In this study, we explored the evolutionary conflict between mimicry and hybridization in woodpeckers. Based on the selective tradeoff hypothesis, we expected that mimicry complexes will start to evolve once the constraint of maladaptive hybridization is relaxed. Hence, we predicted limited overlap in the divergence times between hybridizing species pairs and members of a mimicry complex. This prediction was supported by clear tipping point in the probability of hybridization and mimicry at ca 9 million years of divergence. Around this timepoint, the probability of hybridization approaches zero while the probability of belonging to a mimicry complex increases. This finding is only correlational and remains to be confirmed in other taxonomic groups. Nonetheless, our results suggest a selective tradeoff between evolving interspecific mimicry and avoiding maladaptive hybridization in woodpeckers. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
19. Balancing Gains and Losses—A Research Note on Tradeoffs in the Case of Non-Alcoholic Wines in Germany.
- Author
-
Schulz, Frederik Nikolai, Kugel, Alexander A., and Hanf, Jon H.
- Abstract
Non-alcoholic alternatives are gaining growing significance within the German beverage sector. In this context, the German wine industry is increasingly focusing on non-alcoholic wines, whose market has developed dynamically in recent years. While the technologies used, the sensory characteristics and the marketing of the products are frequently addressed in the literature, the consideration of sustainability impacts has so far been largely neglected. This applies in particular to the view of all three dimensions of sustainability. These are examined more closely in this review with regard to tradeoffs, which indicate that positive aspects in one dimension go hand in hand with a loss in the other. It can be shown that tradeoffs in the production and marketing of non-alcoholic wines arise both within and between the three sustainability dimensions. Exemplary of this is the increased use of resources in the course of alcohol removal. At the same time, an emerging market segment holds positive aspects from an economic perspective. Ultimately, the consideration of social sustainability is marked by the health science and political debate around the reduction in alcohol consumption and the simultaneous increase in the consumption of non-alcoholic alternatives. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
20. Water storage capacity is inversely associated with xylem embolism resistance in tropical karst tree species.
- Author
-
Liu, Yan-Yan, Chao, Lin, Li, Zhong-Guo, Ma, Lin, Hu, Bao-Qing, Zhu, Shi-Dan, and Cao, Kun-Fang
- Subjects
- *
WATER storage , *KARST , *HYDRAULIC conductivity , *XYLEM ,WOOD density - Abstract
Tropical karst habitats are characterized by limited and patchy soil, large rocky outcrops and porous substrates, resulting in high habitat heterogeneity and soil moisture fluctuations. Xylem hydraulic efficiency and safety can determine the drought adaptation and spatial distribution of woody plants growing in karst environments. In this study, we measured sapwood-specific hydraulic conductivity (K s), vulnerability to embolism, wood density, saturated water content, and vessel and pit anatomical characteristics in the branch stems of 12 evergreen tree species in a tropical karst seasonal rainforest in southwestern China. We aimed to characterize the effects of structural characteristics on hydraulic efficiency and safety. Our results showed that there was no significant correlation between K s and hydraulic safety across the tropical karst woody species. K s was correlated with hydraulic vessel diameter (r = 0.80, P < 0.05) and vessel density (r = −0.60, P < 0.05), while the stem water potential at 50 and 88% loss of hydraulic conductivity (P 50 and P 88) were both significantly correlated with wood density (P < 0.05) and saturated water content (P = 0.052 and P < 0.05, respectively). High stem water storage capacity was associated with low cavitation resistance possibly because of its buffering the moisture fluctuations in karst environments. However, both K s and P 50 /P 88 were decoupled from the anatomical traits of pit and pit membranes. This may explain the lack of tradeoff between hydraulic safety and efficiency in tropical karst evergreen tree species. Our results suggest that diverse hydraulic trait combination may facilitate species coexistence in karst environments with high spatial heterogeneity. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
21. Correlation of plasticities to drought and shade: implications for environmental niche overlap in drylands.
- Author
-
Escobedo, Víctor M., Rios, Rodrigo S., Salgado‐Luarte, Cristian, and Gianoli, Ernesto
- Subjects
- *
PHENOTYPIC plasticity , *WATER supply , *ARID regions , *NUMBERS of species , *PLANT communities , *SHRUBLANDS - Abstract
Phenotypic plasticity can increase the extent of the environmental gradient occupied by a species (niche breadth) and modify the portion of niche space shared among co‐occurring species (niche overlap). Thus, phenotypic plasticity may play a role in community assembly processes. Given that plants deal with a multivariate environment, and that functional traits are often correlated, plastic responses to different environmental factors are likely correlated. However, the implications of correlations of plasticities for niche overlap remain unexplored. Here, we present and evaluate a conceptual framework that links correlations of plasticities and niche overlap patterns among co‐occurring plant species. We specifically tested in an arid shrubland whether positive, negative, or null correlations between plasticity to light and water availability would be associated with patterns of high, low, or random niche overlap, respectively. Field data identified light and water availability as key factors shaping herbaceous plant community structure. We estimated species' niche breadth and niche overlap using two‐dimensional kernel–density estimations (NOK) and standardised effect sizes of Pianka's niche overlap index (OSES). We measured phenotypic plasticity to light and water availability in the six most abundant species in a greenhouse experiment. We used the plasticity index (PI) to test 1) the relationship between plasticity to light and water availability, and 2) the association between overall plasticity (average PI across traits) and niche breadth. We found a positive relationship between plasticity to light and water availability. Increased overall plasticity was associated with a broader niche breadth. Both NOK and OSES estimations indicated a significant niche overlap pattern. Results supported one of the predictions of our conceptual framework: that a positive correlation of plasticities would lead to increased niche overlap. The verified conceptual framework broadens our understanding of the role of phenotypic plasticity in plant community coexistence. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
22. Reliability–Security Tradeoff Analysis in mmWave Ad Hoc–based CPS.
- Author
-
Ju, Ying, Yang, Mingjie, Chakraborty, Chinmay, Liu, Lei, Pei, Qingqi, Xiao, Ming, and Yu, Keping
- Subjects
CONJOINT analysis ,PHYSICAL layer security ,AD hoc computer networks ,INFORMATION technology security ,CYBER physical systems - Abstract
Cyber-physical systems (CPS) offer integrated resolutions for various applications by combining computer and physical components and enabling individual machines to work together for much more excellent benefits. The ad hoc–based CPS provides a promising architecture due to its decentralized nature and destructive-resistance. A growing number of information leakage events in CPSs and the following serious consequences have aroused ubiquitous concern about information security. In this article, we combine physical layer security solutions and millimeter-wave (mmWave) techniques to safeguard the ad hoc network and investigate the reliability-security tradeoff by taking user demands for the network into account, where eavesdroppers attempt to intercept messages. For the secrecy enhancements, we adopt an artificial noise (AN) assisted transmission scheme, in which AN is employed to create non-cancellable interference to eavesdroppers. The reliability and security are correspondingly characterized by the connection outage probability and secrecy outage probability, and their analytical expressions of them are attained through theoretical analysis for the purpose of the tradeoff issue discussion. Our results reveal that secrecy performance in mmWave ad hoc networks gains significant improvement through the use of AN. It also shows that given total transmit power, there exists a tradeoff between reliability and security to achieve optimal outage performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
23. Diving behavior in semi-aquatic Anolis lizards results in heat loss with sex-specific cooling tolerance.
- Author
-
Martin, Alexandra M., Boccia, Christopher K., and Swierk, Lindsey
- Abstract
Males and females often differ in use of antipredator behaviors, particularly when antipredator behavior comes at the cost of missed mating opportunities or territory defense. When using thermally suboptimal refugia, ectotherms are especially vulnerable to these costs, as their performance is linked to body temperature. To flee from predators, semi-aquatic Anolis lizards dive underwater for long periods and rebreathe from a bubble of air. We hypothesized that using aquatic refugia would result in body heat loss, that dive duration is influenced by sex, and that oxygen consumption when diving would help explain sex differences. We tested these hypotheses by measuring dive length and body temperatures in A. aquaticus, and by recording oxygen consumption and final oxygen partial pressure during controlled dives in several semi-aquatic Anolis species. Not only was there a significant thermal cost to diving, but A. aquaticus males and females appeared to tolerate different levels of this cost: males re-emerged from water more quickly and at higher body temperatures than did females. Body temperature decreased according to an exponential decay function, dropping up to 6 °C in 5 min. Oxygen consumption rates in semi-aquatic anoles were primarily explained by the expected allometric scaling relationship with mass and, therefore, are unlikely to lead to sex differences in physiological limits to dive times. Instead, shorter male dives may help them maintain physiological performance, mating opportunities or territory defense. Antipredator diving behavior is physiologically costly but undoubtedly beneficial to both sexes, highlighting the need for further study of sex-based antipredator optimization. Significance statement: To avoid predators, semi-aquatic Anolis lizards can dive underwater and remain there for an extended time by rebreathing a bubble of air over their heads. In this study, we reveal that diving to escape predators also comes with a cost: submersion in water reduces lizard body temperatures. Reduced body temperature can impair a lizard’s ability to move quickly and defend mates or territories, suggesting that there may be divergent diving behaviors in males and females. Our findings confirm that males do indeed spend less time underwater than females. We measured oxygen consumption during dives, and our data suggest that sex differences in diving behavior are unrelated to oxygen use. This study sheds light on the sex-specific balance of antipredator behaviors and the maintenance of optimal body temperatures, and more broadly contributes insight into adaptive responses to environmental challenges. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. Free-Space Optical (FSO) Satellite Networks Performance Analysis: Transmission Power, Latency, and Outage Probability
- Author
-
Jintao Liang, Aizaz U. Chaudhry, Eylem Erdogan, Halim Yanikomeroglu, Gunes Karabulut Kurt, Peng Hu, Khaled Ahmed, and Stephane Martel
- Subjects
Free-space optical satellite networks ,network latency ,optical inter-satellite link ,optical uplink/downlink ,satellite transmission power ,tradeoff ,Transportation engineering ,TA1001-1280 ,Transportation and communications ,HE1-9990 - Abstract
In free-space optical satellite networks (FSOSNs), satellites can have different laser inter-satellite link (LISL) ranges for connectivity. As the LISL range increases, the number of satellites from among all the satellites in the constellation that will be needed on the shortest path between a source and a destination ground station decrease, and thereby the number of the LISLs on the shortest path decreases. Greater LISL ranges can reduce network latency of the path but can also result in an increase in transmission power for satellites on the path. Consequently, this tradeoff between satellite transmission power and network latency should be investigated, and in this work we examine it in FSOSNs drawing on the Starlink Phase 1 Version 3 (i.e., the latest version of Starlink's Phase 1) and Kuiper Shell 2 (i.e., Kuiper's biggest shell) constellations for different LISL ranges and different inter-continental connections. We use appropriate system models for calculating the average satellite transmission power (i.e., the average of the transmission power of all satellites on the shortest path) and network latency (i.e., the end-to-end latency of the shortest path). The results show that the mean network latency (i.e., the mean of network latency over all time slots) decreases and mean average satellite transmission power (i.e., the mean of average satellite transmission power over all time slots) increases with an increase in LISL range. For the Toronto–Sydney inter-continental connection in an FSOSN with Starlink's Phase 1 Version 3 constellation, when the LISL range is approximately 2,900 km, the mean network latency and mean average satellite transmission power intersect are approximately 135 ms and 380 mW, respectively. For an FSOSN with the Kuiper Shell 2 constellation in this inter-continental connection, this LISL range is around 3,800 km, and the two parameters are approximately 120 ms and 700 mW, respectively. For the Toronto–Istanbul and Toronto–London inter-continental connections, the LISL ranges at the intersection are different and vary from 2,600 km to 3,400 km. Furthermore, we analyze outage probability performance of optical uplink/downlink due to atmosphere attenuation and turbulence.
- Published
- 2024
- Full Text
- View/download PDF
25. Resource Efficient and Robust RSMA for Visible Light Communications
- Author
-
Jianfei Hu, Chen Sun, Jiaheng Wang, Xiqi Gao, Liang Xia, and Qixing Wang
- Subjects
Rate splitting multiple access ,resource efficiency ,energy efficiency ,spectral efficiency ,tradeoff ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
Spectral efficiency (SE) and energy efficiency (EE) are two main metrics for the transmit design in Visible Light Communications (VLC). However, the SE-optimal and EE-optimal strategies may be in conflict with each other to some extent. In this paper, we investigate the the tradeoff between EE and SE in rate splitting multiple access (RSMA)-aided VLC systems to maximize the system resource efficiency (RE) taking both perfect and imperfect channel state information (CSI) into consideration. For the scenarios with perfect CSI, we explore the joint precoding design and common rate allocation to maximize the RE of RSMA-aided VLC systems under the constraints of quality of service (QoS) and linear operation region (LoR) of LED, and propose a primal-dual-gradient-based precoding strategy. Furthermore, in the presence of CSI estimation errors, we propose a worst-case robust precoding design by exploiting quadratic transform and $\mathcal {S}$-Procedure. Numerical results indicate that the proposed resource efficient RSMA algorithm achieves the tradeoff between EE and SE.
- Published
- 2024
- Full Text
- View/download PDF
26. Climate-Driven Legacies in Simulated Microbial Communities Alter Litter Decomposition Rates
- Author
-
Wang, Bin and Allison, Steven D
- Subjects
Biological Sciences ,Ecology ,Climate Action ,microbiome ,composition ,decomposition ,trait ,tradeoff ,climate ,litter ,legacy ,Evolutionary Biology ,Evolutionary biology ,Ecological applications - Abstract
The mechanisms underlying diversity-functioning relationships have been a consistent area of inquiry in biogeochemistry since the 1950s. Though these mechanisms remain unresolved in soil microbiomes, many approaches at varying scales have pointed to the same notion—composition matters. Confronting the methodological challenge arising from the complexity of microbiomes, this study used the model DEMENTpy, a trait-based modeling framework, to explore trait-based drivers of microbiome-dependent litter decomposition. We parameterized DEMENTpy for five sites along a climate gradient in Southern California, United States, and conducted reciprocal transplant simulations analogous to a prior empirical study. The simulations demonstrated climate-dependent legacy effects of microbial communities on plant litter decomposition across the gradient. This result is consistent with the previous empirical study across the same gradient. An analysis of community-level traits further suggests that a 3-way tradeoff among resource acquisition, stress tolerance, and yield strategies influences community assembly. Simulated litter decomposition was predictable with two community traits (indicative of two of the three strategies) plus local environment, regardless of the system state (transient vs. equilibrium). Although more empirical confirmation is still needed, community traits plus local environmental factors (e.g., environment and litter chemistry) may robustly predict litter decomposition across spatial-temporal scales. In conclusion, this study offers a potential trait-based explanation for climate-dependent community effects on litter decomposition with implications for improved understanding of whole-ecosystem functioning across scales.
- Published
- 2022
27. Age at first reproduction and senescence in a short‐lived wild mammal.
- Author
-
Allain, Jimmy, Tissier, Mathilde, Bergeron, Patrick, Garant, Dany, and Réale, Denis
- Subjects
- *
AGING , *LIFE history theory , *BIODEGRADATION , *LONGEVITY , *FEMALES , *AGE , *MAMMALS - Abstract
Senescence is the degradation of biological functions with increasing age. Its existence and relationship with life‐history strategies remains poorly studied in short‐lived wild vertebrate species. We investigated the relationships between age at first reproduction (AFR), reproductive senescence and longevity in an eastern chipmunk Tamias striatus population, where the first opportunity to breed is conditioned by pulses of seed production by trees (i.e. masts). We used 11 years of data from a longitudinal study, in which females breed for the first time at seven, 15 or 22 months of age and males at seven or 15 months of age. We first assessed the effect of age on three traits associated with breeding performance, namely the number of offspring produced, and the probability of producing an offspring. We then tested whether an earlier AFR accelerated reproductive senescence and reduced survival of both males and females. We found sex‐specific relationships between AFR and senescence. Females reproducing at 15 or 22 months of age showed reproductive senescence, but early‐breeding females did not show any decline in reproductive performance at an older age. Also, although we observed reproductive senescence in males, it was not affected by AFR. Our results are consistent with studies highlighting the existence of reproductive senescence in small, wild mammals. Importantly, we provide the first evidence that AFR can strongly influence the patterns of senescence in small short‐lived species, and does it in a sex‐specific way. Our results highlight the importance of studying life‐history strategies in both males and females when studying senescence in the wild. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. Relationships between ecosystem functions vary among years and plots and are driven by plant species richness.
- Author
-
Argens, Laura, Weisser, Wolfgang W., Ebeling, Anne, Eisenhauer, Nico, Lange, Markus, Oelmann, Yvonne, Roscher, Christiane, Schielzeth, Holger, Schmid, Bernhard, Wilcke, Wolfgang, and Meyer, Sebastian T.
- Subjects
- *
SPECIES diversity , *PLANT species , *ECOSYSTEM management , *ECOSYSTEMS , *ECOSYSTEM services , *GRASSLANDS , *PLANT species diversity , *PLATEAUS - Abstract
Ecosystem management aims at providing many ecosystem services simultaneously. Such ecosystem service multifunctionality can be limited by tradeoffs and increased by synergies among the underlying ecosystem functions (EF), which need to be understood to develop targeted management. Previous studies found differences in the correlation between EFs. We hypothesised that correlations between EFs are variable even under the controlled conditions of a field experiment and that seasonal and annual variation, plant species richness, and plot identity (identity effects of plots, such as the presence and proportion of functional groups) are drivers of these correlations. We used data on 31 EFs related to plants, consumers, and physical soil properties that were measured over 5 to 19 years, up to three times per year, in a temperate grassland experiment with 80 different plots, constituting six sown plant species richness levels (1, 2, 4, 8, 16, 60 species). We found that correlations between pairs of EFs were variable, and correlations between two particular EFs could range from weak to strong or negative to positive correlations among the repeated measurements. To determine the drivers of pairwise EF correlations, the covariance between EFs was partitioned into contributions from species richness, plot identity, and time (including years and seasons). We found that most of the covariance for synergies was explained by species richness (26.5%), whereas for tradeoffs, most covariance was explained by plot identity (29.5%). Additionally, some EF pairs were more affected by differences among years and seasons, showing a higher temporal variation. Therefore, correlations between two EFs from single measurements are insufficient to draw conclusions on tradeoffs and synergies. Consequently, pairs of EFs need to be measured repeatedly under different conditions to describe their relationships with more certainty and be able to derive recommendations for the management of grasslands. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. Discussing the basic ecological relations of sand dune vegetation process.
- Author
-
LIU Zhimin, YU Haibin, and WANG Haiyang
- Abstract
Dune is often considered as a degraded ecosystem. Natural vegetation restoration and stable artificial vegetation construction are the basic means restoring dune ecosystem. Based on long-term study of dune ecosystem, by taking into consideration both the philosophical principles of unity of opposites and dynamic change, and related ecological theories, we put forward some ecological relations that should be paid attention to in the study of vegetation assembly from the perspective of the uniqueness of dune ecosystem. We discussed the necessity of coupling relationships of scale-pattern-process and the transformation of synergy-tradeoff relationships, interpreted the importance of distinguishing sand dune stabilized and shifting phases, disturbance and stress, wind erosion and sand burial in the study of vegetation process. We further explored the applied value of niche law or neutral law in the study of dune vegetation process. Finally, we discussed the issues that should be paid attention to in the study of dune vegetation process from the aspects of adaptability to aeolian activities and drought tolerance, physiological and reproductive process, sexual and asexual reproduction of plants. This study would provide theoretical supports for vegetation restoration and stable vegetation construction of dune ecosystem. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. 金沙江下游梯级水电工程库区生态系统服务价值演化及权衡协同关系.
- Author
-
赵旭, 王浩, 赵志龙, and 赵菲菲
- Abstract
Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
31. Activation of immune defences against parasitoid wasps does not underlie the cost of infection.
- Author
-
Leitão, Alexandre B., Geldman, Emma M., and Jiggins, Francis M.
- Subjects
DROSOPHILA melanogaster ,WASPS ,BODY size ,DEVELOPMENTAL delay ,FACTORS of production - Abstract
Parasites reduce the fitness of their hosts, and different causes of this damage have fundamentally different consequences for the evolution of immune defences. Damage to the host may result from the parasite directly harming its host, often due to the production of virulence factors that manipulate host physiology. Alternatively, the host may be harmed by the activation of its own immune defences, as these can be energetically demanding or cause self-harm. A well-studied model of the cost of infection is Drosophila melanogaster and its common natural enemy, parasitoid wasps. Infected Drosophila larvae rely on humoral and cellular immune mechanisms to form a capsule around the parasitoid egg and kill it. Infection results in a developmental delay and reduced adult body size. To disentangle the effects of virulence factors and immune defences on these costs, we artificially activated anti-parasitoid immune defences in the absence of virulence factors. Despite immune activation triggering extensive differentiation and proliferation of immune cells together with hyperglycaemia, it did not result in a developmental delay or reduced body size. We conclude that the costs of infection do not result from these aspects of the immune response and may instead result from the parasite directly damaging the host. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
32. Intersection Searching amid Tetrahedra in Four Dimensions
- Author
-
Ezra, Esther and Sharir, Micha
- Published
- 2024
- Full Text
- View/download PDF
33. Joint mode selection and resource allocation to flexibly guarantee quality of service for downlink MISO-NOMA systems
- Author
-
Zhixin Zhao, Dong Wang, Hongwei Zhang, and Xiaotao Huang
- Subjects
NOMA ,Beamforming ,Successive interference cancellation ,Mode selection ,Tradeoff ,Rate region ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Non-orthogonal multiple access (NOMA) with successive interference cancellation (SIC) detection, known as SIC NOMA, enjoys higher spectral efficiency (SE), but suffers increased processing complexity and additional error propagation compared to Non-SIC NOMA, in which the receivers directly detect their own signals from the superposed signal without SIC detection. We propose a joint Mode Selection and Power Allocation (MSPA) scheme that can flexibly realize different kinds of tradeoffs while guaranteeing minimum rate requirements (MRRs) for two-user MISO-NOMA downlink. Specifically, we first obtain rate region boundaries that guarantee two users’ MRRs for two candidate modes: maximum-ratio transmission (MRT)/SIC NOMA and minimum mean square error beamforming (MMSE-BF)/Non-SIC NOMA. We then construct an expression of power allocation factors (transmit power factors) that can satisfy the two users’ MRRs for MRT/SIC NOMA (MMSE-BF/Non-SIC NOMA) by introducing a parameter λ. Finally, we achieve outer boundary of the union of the two modes' rate regions by mode selection and derive expected users' rates on it. Numerical results demonstrate that the proposed MSPA can improve SE and flexibly achieve different kinds of tradeoffs by adjusting λ, while guaranteeing the two users’ MRRs simultaneously for high signal to noise ratio (SNR) scenario and alternately guaranteeing the two users’ MRRs for low SNR scenario.
- Published
- 2024
- Full Text
- View/download PDF
34. Activation of immune defences against parasitoid wasps does not underlie the cost of infection
- Author
-
Alexandre B. Leitão, Emma M. Geldman, and Francis M. Jiggins
- Subjects
Drosophila ,parasitoid ,immunity ,cost ,tradeoff ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Parasites reduce the fitness of their hosts, and different causes of this damage have fundamentally different consequences for the evolution of immune defences. Damage to the host may result from the parasite directly harming its host, often due to the production of virulence factors that manipulate host physiology. Alternatively, the host may be harmed by the activation of its own immune defences, as these can be energetically demanding or cause self-harm. A well-studied model of the cost of infection is Drosophila melanogaster and its common natural enemy, parasitoid wasps. Infected Drosophila larvae rely on humoral and cellular immune mechanisms to form a capsule around the parasitoid egg and kill it. Infection results in a developmental delay and reduced adult body size. To disentangle the effects of virulence factors and immune defences on these costs, we artificially activated anti-parasitoid immune defences in the absence of virulence factors. Despite immune activation triggering extensive differentiation and proliferation of immune cells together with hyperglycaemia, it did not result in a developmental delay or reduced body size. We conclude that the costs of infection do not result from these aspects of the immune response and may instead result from the parasite directly damaging the host.
- Published
- 2023
- Full Text
- View/download PDF
35. CROP ATTRIBUTES, FARM DECISIONS CROP SPECIFIC POLICIES IN THE CONTEXT OF SUSTAINABILITY OF PRODUCTION IN ETHIOPIA
- Author
-
Mohammed Endris Harun and Belaineh Legesse
- Subjects
pro-poor policy ,tradeoff ,subsidy ,agricultural policy ,Agriculture - Abstract
Ethiopia’s government has created a number of policies and programs to address the urgent issue of rising food prices. Extension and regulation initiatives aiming at influencing the production and marketing are frequently used in conjunction with them. However, lack of indices on relative importance of individual crops results poor policy outcomes. Analyzing household decision dynamics and how household decisions respond to policies is crucial to reduce persistent complaints from recipients and avoid negative policy outcomes. For this study, data from 392 randomly chosen households of Kewot woreda was used. Sorghum found with higher calorie index per profit while mung bean was found higher profit index. Crop diversification found inefficient that arise from profitability differences and return to scale. Additionally multiple objectives could be met using tradeoffs among different crop benefits. This study also summarizes major findings from previous crop-related policies and linked them to specific crop characteristics. It is advised that policies be adjusted to reflect the value, character, and utility of crops.
- Published
- 2023
- Full Text
- View/download PDF
36. The Circadian Clock Coordinates the Tradeoff between Adaptation to Abiotic Stresses and Yield in Crops.
- Author
-
Xu, Hang, Zuo, Yi, Wei, Jian, and Wang, Lei
- Subjects
- *
CIRCADIAN rhythms , *ABIOTIC stress , *CROP yields , *YIELD stress , *PLANT breeding , *SESSILE organisms - Abstract
Simple Summary: The circadian clock plays a crucial role in helping plants to effectively acclimate to ever-changing environmental conditions. The proper functioning of the circadian clock is integral to the growth and development of plants. In crops, the circadian clock system exerts a multifaceted influence on yield and the response to abiotic stress. This review provides a comprehensive overview of the mechanisms through which the components of a crop's circadian clock impact its response to abiotic stress and yield. We propose that the circadian clock may orchestrate the balance between abiotic stresses and yield in crops, which is useful for the future molecular design of crop breeding. Plants have evolved a circadian clock to adapt to ever-changing diel and seasonal environmental conditions. The circadian clock is generally considered an internal system that has evolved to adapt to cyclic environmental cues, especially diel light and temperature changes, which is essential for higher plants as they are sessile organisms. This system receives environmental signals as input pathways which are integrated by circadian core oscillators to synchronize numerous output pathways, such as photosynthesis, the abiotic stress response, metabolism, and development. Extreme temperatures, salinity, and drought stresses cause huge crop losses worldwide, imposing severe pressure on areas of agricultural land. In crop production, the circadian system plays a significant role in determining flowering time and responding to external abiotic stresses. Extensive studies over the last two decades have revealed that the circadian clock can help balance the tradeoff between crop yield-related agronomic traits and adaptation to stress. Herein, we focus on summarizing how the circadian clock coordinates abiotic stress responses and crop yield. We also propose that there might be an urgent need to better utilize circadian biology in the future design of crop breeding to achieve high yields under stress conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
37. Planning Benefit-Risk Assessments Using Visualizations.
- Author
-
Colopy, Michael W., Gakava, Lovemore, and Chen, Chen
- Subjects
DRUG approval ,DRUG efficacy ,CHRONIC diseases ,INVESTIGATIONAL drugs ,RISK assessment ,DECISION making ,DRUG development ,VISUALIZATION ,DRUG side effects ,COMORBIDITY - Abstract
A Benefit Risk Assessment Plan (BRAP) describes the assessments planned to determine whether the benefits of an investigational drug outweigh the risks. The plan can have two sections, one with timelines for aligning resources with decision milestones and the other for pre-specifying assessments for decision milestones. Regulatory guidance recommends a proactive planning process over an ad-hoc process. However, very little has been published about proactive plans themselves. This article works through a hypothetical example visualizing a series of assessments across the drug development lifecycle. Based on a regulatory framework, the planning process starts with assessing the medical condition and current treatment options. These early assessments bring out major considerations in assessing the investigational drug. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. Design and Analysis of High Performance Heterogeneous Block-based Approximate Adders.
- Author
-
FARAHMAND, EBRAHIM, ALIMAHANI, HANIF, MUHAMMAD ABDULLAH, and SHAFIQUE, MUHAMMAD
- Subjects
ERROR rates ,APPROXIMATION error ,FIGURATIVE art - Abstract
Approximate computing is an emerging paradigm to improve the power and performance efficiency of errorresilient applications. As adders are one of the key components in almost all processing systems, a significant amount of research has been carried out toward designing approximate adders that can offer better efficiency than conventional designs; however, at the cost of some accuracy loss. In this article, we highlight a new class of energy-efficient approximate adders, namely, Heterogeneous Block-based Approximate Adders (HBAAs), and propose a generic configurable adder model that can be configured to represent a particular HBAA con- figuration. An HBAA, in general, is composed of heterogeneous sub-adder blocks of equal length, where each sub-adder can be an approximate sub-adder and have a different configuration. The sub-adders are mainly approximated through inexact logic and carry truncation. Compared to the existing design space, HBAAs provide additional design points that fall on the Pareto-front and offer a better quality-efficiency tradeoff in certain scenarios. Furthermore, to enable efficient design space exploration based on user-defined constraints, we propose an analytical model to efficiently evaluate the Probability Mass Function (PMF) of approximation error and other error metrics, such as Mean Error Distance (MED), Normalized Mean Error Distance (NMED), and Error Rate (ER) of HBAAs. The results show that HBAA configurations can provide around 15% reduction in area and up to 17% reduction in energy compared to state-of-the-art approximate adders. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. CO2 pollution reduction: a tradeoff for fully fuzzy parameters in a megaproject optimization.
- Author
-
Paryzad, Behzad and Eshghi, Kourosh
- Subjects
NOXIOUS weeds ,POLLUTION ,EVOLUTIONARY algorithms ,FUZZY algorithms ,DECISION making - Abstract
Purpose: This paper aims to conduct a fuzzy discrete time cost quality risk in the ambiguous mode CO
2 tradeoff problem (FDTCQRP*TP) in a megaproject based on fuzzy ground. Design/methodology/approach: A combinatorial evolutionary algorithm using Fuzzy Invasive Weed Optimization (FIWO) is used in the discrete form of the problem where the parameters are fully fuzzy multi-objective and provide a space incorporating all dimensions of the problem. Also, the fuzzy data and computations are used with the Chanas method selected for the computational analysis. Moreover, uncertainty is defined in FIWO. The presented FIWO simulation, its utility and superiority are tested on sample problems. Findings: The reproduction, rearrangement and maintaining elite invasive weeds in FIWO can lead to a higher level of accuracy, convergence and strength for solving FDTCQRP*TP fuzzy rules and a risk ground in the ambiguous mode with the emphasis on the necessity of CO2 pollution reduction. The results reveal the effectiveness of the algorithm and its flexibility in the megaproject managers' decision making, convergence and accuracy regarding CO2 pollution reduction. Originality/value: This paper offers a multi-objective fully fuzzy tradeoff in the ambiguous mode with the approach of CO2 pollution reduction. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
40. CROP ATTRIBUTES, FARM DECISIONS CROP SPECIFIC POLICIES IN THE CONTEXT OF SUSTAINABILITY OF PRODUCTION IN ETHIOPIA.
- Author
-
Harun, Mohammed Endris and Legesse, Belaineh
- Subjects
CROPS ,FOOD prices ,MUNG bean ,CROP diversification ,RETURNS to scale ,SUSTAINABILITY - Abstract
Ethiopia's government has created a number of policies and programs to address the urgent issue of rising food prices. Extension and regulation initiatives aiming at influencing the production and marketing are frequently used in conjunction with them. However, lack of indices on relative importance of individual crops results poor policy outcomes. Analyzing household decision dynamics and how household decisions respond to policies is crucial to reduce persistent complaints from recipients and avoid negative policy outcomes. For this study, data from 392 randomly chosen households of Kewot woreda was used. Sorghum found with higher calorie index per profit while mung bean was found higher profit index. Crop diversification found inefficient that arise from profitability differences and return to scale. Additionally multiple objectives could be met using tradeoffs among different crop benefits. This study also summarizes major findings from previous crop-related policies and linked them to specific crop characteristics. It is advised that policies be adjusted to reflect the value, character, and utility of crops. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
41. Distribution of N and recently fixed C among a common mycorrhizal network linking an invasive plant, Solidago canadensis, and a native plant, Kummerowia striata.
- Author
-
Awaydul, Awagul, Xiao, Jing, Chen, Xin, Koide, Roger, Yuan, Yongge, and Cheng, Lei
- Subjects
- *
INVASIVE plants , *NATIVE plants , *GOLDENRODS , *PLANT species , *INTRODUCED species , *PLANT invasions - Abstract
The invasive plant species, Solidago canadensis, often shares a common mycorrhizal network (CMN) with native plant species in southeast China. We ask whether the transfer of carbon (C) and nitrogen (N) among the invasive S. canadensis, the native Kummerowia striata and their CMN could contribute to the invasiveness of S. canadensis.We conducted a microcosm experiment in which a CMN was established on S. canadensis and K. striata. We used 13CO2 pulse‐labelling to quantify the relative contribution of recently fixed C from the two host species to the CMN. We also calculated the relative N distribution to each host species from the CMN.We found that 89% of the recently fixed C in the CMN originated from S. canadensis, while 11% originated from K. striata. We also found that the CMN distributed 77% of the N it absorbed to S. canadensis and 23% to K. striata.Our results suggest that the unequal distribution of N from a CMN to the invasive and native plant species is related to the unequal contribution of C from the plant species. This mechanism could contribute to invasion of native communities by alien species when there is a stoichiometric exchange of limiting nutrients for C, and when alien species contribute more C to the CMN than natives. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
42. Analysis of the capital structure of startups in light of the tradeoff and pecking order theories.
- Author
-
De Carvalho Colombo, Gabriela, da Costa Gomes, Matheus, Augusto Eça, João Paulo, and Ribeiro do Valle, Maurício
- Subjects
CAPITAL structure ,NEW business enterprises ,CAPITAL investments ,STARTUP costs ,RISK management in business ,SUBSIDIES ,INTANGIBLE property ,PROFITABILITY ,OPTIONS (Finance) ,PUBLIC debts - Abstract
Copyright of REGEPE Entrepreneurship & Small Business Journal is the property of Revista de Empreendedorismo e Gestao de Pequenas Empresas (REGEPE) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
- Full Text
- View/download PDF
43. Vertical and horizontal gene transfer tradeoffs direct plasmid fitness
- Author
-
Jonathan H Bethke, Helena R Ma, Ryan Tsoi, Li Cheng, Minfeng Xiao, and Lingchong You
- Subjects
conjugation ,fitness ,plasmid ,resistance ,tradeoff ,Biology (General) ,QH301-705.5 ,Medicine (General) ,R5-920 - Abstract
Abstract Plasmid fitness is directed by two orthogonal processes—vertical transfer through cell division and horizontal transfer through conjugation. When considered individually, improvements in either mode of transfer can promote how well a plasmid spreads and persists. Together, however, the metabolic cost of conjugation could create a tradeoff that constrains plasmid evolution. Here, we present evidence for the presence, consequences, and molecular basis of a conjugation‐growth tradeoff across 40 plasmids derived from clinical Escherichia coli pathogens. We discover that most plasmids operate below a conjugation efficiency threshold for major growth effects, indicating strong natural selection for vertical transfer. Below this threshold, E. coli demonstrates a remarkable growth tolerance to over four orders of magnitude change in conjugation efficiency. This tolerance fades as nutrients become scarce and horizontal transfer attracts a greater share of host resources. Our results provide insight into evolutionary constraints directing plasmid fitness and strategies to combat the spread of antibiotic resistance.
- Published
- 2022
- Full Text
- View/download PDF
44. Change and Tradeoff/Synergy Analysis of Watershed Ecosystem Services: A Case Study of Qinghai Lake Basin.
- Author
-
Wu, Xueqing, Zhang, Lele, Gao, Liming, Li, Yankun, and Liu, Xuanchen
- Abstract
Understanding the tradeoffs/synergies between ecosystems is crucial to effective watershed ecosystem management and sustainable development. In this study, the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and Carnegie Ames Stanford Approach (CASA) models were utilized to estimate four ecosystem services (ESs), including water conservation capacity, soil retention, habitat quality, and carbon storage services, in Qinghai Lake Basin between 2000 and 2018. Local Indicators of Spatial Association (LISA) and tradeoffs/synergies criterion (TSC) were used to reveal the relationships between the ESs. The results show that the water conservation capacity, soil retention, habitat quality, and carbon storage service in Qinghai Lake Basin all increased between 2000 and 2018. TSC and LISA revealed that carbon storage and habitat quality, habitat quality and water conservation capacity, and carbon storage and soil retention had the same relationship, as did habitat quality and soil retention. In addition, LISA showed that the relationships between ESs are mainly based on high high clusters that concentrate in the middle of the basin. The analysis also revealed obvious spatial heterogeneity. This study aims to compensate the research deficiencies that affected previous studies of the Qinghai Lake Basin and provide a point of reference for the sustainable development of the basin. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. Analysis of the capital structure of startups in light of the tradeoff and pecking Order theories
- Author
-
Gabriela de Carvalho Colombo, Matheus da Costa Gomes, João Paulo Augusto Eça, and Maurício Ribeiro do Valle
- Subjects
Startup ,Tradeoff ,Pecking Order ,Fundraising ,Business ,HF5001-6182 - Abstract
Purpose: Startups have significant differences compared to other companies. They have many intangible assets (e.g., team tenure and experience of founders), are risky, and tend not to generate profits in their initial years (Heirman & Clarysse, 2007; Weber & Zulehner, 2009). Does the startups’ financing choice also differ from that of traditional companies? We analyzed the capital structure of startups in their first years of life based on the classic tradeoff and pecking order theories. Methodology/approach: We collected data on 40 startups in the city of Ribeirão Preto, São Paulo, Brazil, through a questionnaire on the profiles of the founders, company characteristics, bottom-line performance and financing sources. The data collected covered the year of founding and the three subsequent years. Findings: The results indicated that these startups mainly financed themselves through the founders’ capital in all four years covered. Only in the third year did they start using resources generated internally, indicating pecking order adherence. However, the presence of angel investors and government subsidies contrasted with the absence of bank debt. In line with the tradeoff theory, bank debt was not a viable financing option in the early years of these firms since they had low profitability and high risk. Theoretical/methodological contributions: We offer a theoretical contribution by analyzing the adequacy of traditional financial theories in the specific context of startups. Originality: The finance literature about startups is scarce, and few studies have analyzed these companies from the capital structure theoretical perspective. Social contributions / for management: We provide a panorama of the financing of startups to support their financial planning regarding fundraising.
- Published
- 2023
- Full Text
- View/download PDF
46. The reimbursement decision speed for oncology new drugs in China and its determinant factors
- Author
-
Xingyue Zhu and Yang Chen
- Subjects
reimbursement ,time to list ,price negotiation ,tradeoff ,drug access ,Public aspects of medicine ,RA1-1270 - Abstract
IntroductionChina has initiated national price negotiations to improve access to innovative drugs. Learning the factors that contributed to the time gap from marketing authorization to reimbursement leads to more clarity to decision-making, which remains under-researched in China.MethodsWe collected new oncology drug approvals that were marketed before 30 Jun 2022, using the Listed Drug Database of the Chinese drug agency. Major information of each approval was obtained from the published review report, including the first approval region (China or the US) and the receipt of expedited review pathways (priority review and conditional approval). The reimbursement lists issued by China National Healthcare Security Administration from 2015 to 2023 were used to determine the reimbursement status of drugs. The duration from marketing authorization to reimbursement was defined as the reimbursement decision speed, and the Cox regression was performed to explore the underlying factors.ResultsA total of 186 oncology approvals were included. More than half of the approvals qualified for reimbursement (110[59.14%]), and the median reimbursement decision speed was accelerated from 540.5 days in the third-round negotiation to 448 days in the seventh-round. Domestic new drugs had a higher probability of being adopted by the Chinese payer than drugs developed by foreign companies (adjusted HR = 3.73, 95% CI 2.42 to 5.75; P < 0.001). Furthermore, new drug applications receiving the regular review pathway were more likely to be reimbursed (adjusted HR = 2.15, 95% CI 1.13 to 4.08; P = 0.020) compared to those approved under the conditional approval pathway.DiscussionThese findings indicate that the Chinese government is actively working toward improving access to new oncology drugs. The faster reimbursement decision speed for domestic drugs might be attributed to their pricing advantages and the regulator's efforts to stimulate innovation in the domestic pharmaceutical industry. However, concerns about the uncertainty in drug benefits can affect the reimbursement decision-making, which suggests the delicate tradeoff between drug accessibility and risk involved in the reimbursement process.
- Published
- 2023
- Full Text
- View/download PDF
47. Early adversity and the development of explore–exploit tradeoffs.
- Author
-
Frankenhuis, Willem E. and Gopnik, Alison
- Subjects
- *
SCIENTIFIC literature , *LIFE history theory , *COGNITIVE science , *PHYSIOLOGICAL effects of acceleration , *PHENOTYPIC plasticity - Abstract
This opinion article brings together research on the effects of early adversity, computational accounts of learning, and life-history theory. These bodies of research have independently converged on the finding that exposures to chronic adversity may accelerate maturation, yet synergies between them have hardly been explored. We connect these bodies of research by proposing the hypothesis that early experiences influence hyperparameters that determine the balance between exploration and exploitation. Specifically, we argue that childhood adversity may accelerate a shift from exploration to exploitation, with wide-ranging effects on the adult brain and mind. Understanding which types of adversity accelerate the explore–exploit shift, and formal theory exploring when such a response may be adaptive, are key directions for future work. Childhood adversity can have wide-ranging and long-lasting effects on later life. But what are the mechanisms that are responsible for these effects? This article brings together the cognitive science literature on explore–exploit tradeoffs, the empirical literature on early adversity, and the literature in evolutionary biology on 'life history' to explain how early experience influences later life. We propose one potential mechanism: early experiences influence 'hyperparameters' that determine the balance between exploration and exploitation. Adversity might accelerate a shift from exploration to exploitation, with broad and enduring effects on the adult brain and mind. These effects may be produced by life-history adaptations that use early experience to tailor development and learning to the likely future states of an organism and its environment. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. Seq2seq model for human action recognition based on skeleton and two-layer bidirectional LSTM.
- Author
-
Wei, Shouke, Zhao, Jindong, Li, Junhuai, and Yuan, Meixue
- Subjects
HUMAN activity recognition ,DATA privacy ,CONVOLUTIONAL neural networks ,SKELETON ,SOCIAL interaction - Abstract
Human action recognition (HAR) plays an important role in social interaction in various fields. This study proposes a light-weight skeleton and two-layer bidirectional LSTM-based Seq2Seq model (SB2_Seq2Seq) for HAR to trade off recognition accuracy, users' privacy and computer resource usage. An experiment was conducted to compare the proposed SB2_Seq2Seq with other skeleton-based Seq2Seq models and non-skeleton RGB video frame-based LSTM, CNN and seq2seq models. The UCF50 dataset was used for model evaluation, where 60%, 20% and 20% for model training, validation and testing, respectively. The experimental results show that the proposed model achieves 93.54% accuracy with 0.0214 Mean Square Error (MSE), suggesting that the proposed model outperforms all the other models. Besides, it also shows that the proposed model achieves state-of-the-art accuracy compared with state-of-the-arts methods in literature. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. Experimental Evolution of the TolC-Receptor Phage U136B Functionally Identifies a Tail Fiber Protein Involved in Adsorption through Strong Parallel Adaptation.
- Author
-
Burmeister, Alita R., Tzintzun-Tapia, Eddy, Roush, Carli, Mangal, Ivan, Barahman, Roxanna, Bjornson, Robert D., and Turner, Paul E.
- Subjects
- *
BACTERIOPHAGES , *WHOLE genome sequencing , *ESCHERICHIA coli , *BACTERIAL diversity , *DRUG resistance in bacteria , *MOLECULAR evolution , *BACTERIAL evolution - Abstract
Bacteriophages have received recent attention for their therapeutic potential to treat antibiotic-resistant bacterial infections. One particular idea in phage therapy is to use phages that not only directly kill their bacterial hosts but also rely on particular bacterial receptors, such as proteins involved in virulence or antibiotic resistance. In such cases, the evolution of phage resistance would correspond to the loss of those receptors, an approach termed evolutionary steering. We previously found that during experimental evolution, phage U136B can exert selection pressure on Escherichia coli to lose or modify its receptor, the antibiotic efflux protein TolC, often resulting in reduced antibiotic resistance. However, for TolC-reliant phages like U136B to be used therapeutically, we also need to study their own evolutionary potential. Understanding phage evolution is critical for the development of improved phage therapies as well as the tracking of phage populations during infection. Here, we characterized phage U136B evolution in 10 replicate experimental populations. We quantified phage dynamics that resulted in five surviving phage populations at the end of the 10-day experiment. We found that phages from all five surviving populations had evolved higher rates of adsorption on either ancestral or coevolved E. coli hosts. Using whole-genome and whole-population sequencing, we established that these higher rates of adsorption were associated with parallel molecular evolution in phage tail protein genes. These findings will be useful in future studies to predict how key phage genotypes and phenotypes influence phage efficacy and survival despite the evolution of host resistance. IMPORTANCE Antibiotic resistance is a persistent problem in health care and a factor that may help maintain bacterial diversity in natural environments. Bacteriophages ("phages") are viruses that specifically infect bacteria. We previously discovered and characterized a phage called U136B, which infects bacteria through TolC. TolC is an antibiotic resistance protein that helps bacteria pump antibiotics out of the cell. Over short timescales, phage U136B can be used to evolutionarily "steer" bacterial populations to lose or modify the TolC protein, sometimes reducing antibiotic resistance. In this study, we investigate whether U136B itself evolves to better infect bacterial cells. We discovered that the phage can readily evolve specific mutations that increase its infection rate. This work will be useful for understanding how phages can be used to treat bacterial infections. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
50. How would ecological restoration affect multiple ecosystem service supplies and tradeoffs? A study of mine tailings restoration in China
- Author
-
Weiyang Zhao, Shuyao Wu, Xin Chen, Jiashu Shen, Feili Wei, Delong Li, Laibao Liu, and Shuangcheng Li
- Subjects
Ecosystem service ,Tradeoff ,Ecological restoration ,Mine tailing ,Scenario setting ,Ecology ,QH540-549.5 - Abstract
Ecological restoration is becoming increasingly important in addressing the global crisis of ecosystem degradation. Ecosystem services, as a concept that connects people and natural ecosystems, can be incorporated into the design, practice and evaluation of restoration projects to promote both the socioeconomic and ecological effects of restoration. However, the full incorporation of ecosystem services in landscape-scale restoration projects is still greatly lacking. In this study, we used the Dashihe mine tailings restoration project in Hebei, China, as a case study and analyzed data from field surveys, remote sensing and literature reviews to study the following two questions: 1) How would multiple ecosystem service supply capabilities and their tradeoffs change after ecological restoration; 2) How can multiple ecosystem service supply capabilities be maximized while minimizing their tradeoffs? The supply capabilities of four important ecosystem services (i.e., soil retention, dust deposition, carbon sequestration and habitat maintenance) and their tradeoff intensities under six restoration scenarios were quantified and compared. The results showed that restored ecosystems outperformed unrestored and even the reference conditions in terms of ecosystem service supply enhancement. However, there is still much room for improvement compared to the recommended restoration scenario. The recommended scenario could result in both higher service supplies and lower tradeoff intensities among the services. On this basis, we call for more incorporation of ecosystem service supply and tradeoff analysis in future ecological restoration projects to reverse the declining trends of ecosystem services across the globe.
- Published
- 2023
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.