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Common ragweed (Ambrosia artemisiifolia) is an invasive annual weed that invades heavily disturbed habitats and natural habitats less disturbed by human activities with native plant species in need of protection. Achieving effective control of A. artemisiifolia for the protection of native organisms and the local ecological environment is an ongoing challenge. Based on the growth and development characteristics of A. artemisiifolia, we examined the effectiveness of herbicides in controlling this species and the optimal time for application in the field with the aim of reducing herbicide dosage. Additionally, we analyzed whether the efficiency of low-dose applications for controlling this species might improve with increasing native plant species richness. Our findings indicate that aminopyralid (33 g ai ha−1) was the most suitable herbicide for chemical control of A. artemisiifolia, with optimum application time being during vegetative growth (BBCH 32–35). Application of aminopyralid was found to kill approximately 52% of A. artemisiifolia plants, and more than 75% of the surviving plants did not bloom, thereby reducing seed yield of the population by more than 90%. Compared with the application of high-dose herbicide, the phytotoxicity of aminopyralid to native plants at the applied dose was substantially reduced. After 2 years of application, the relative coverage of A. artemisiifolia significantly decreased, with few plants remaining, whereas the relative coverage of native plants more than doubled, representing an eco-friendly control. Further, there was an increase in the A. artemisiifolia control rate in the plant community with higher native plant species richness at the same herbicide rates and a reduction in seed yield of A. artemisiifolia. Our findings help toward developing control measures to reduce the invasiveness of A. artemisiifolia with low-dose herbicides meanwhile protecting native plants, and then using the species richness of native plant communities to indirectly promote the effectiveness of low-dose herbicide application.

Systems studies of signal transduction pathways that modulate plant growth and immunity are rapidly identifying a large number of interactions within these pathways. These interactions are frequently presented as mechanisms allowing a plant to make proper decisions with regards to how to partition energy and resources in a proposed growth versus immunity tradeoff. This is a reinterpretation of the classical costs of resistance theory that has a long history in the ecology research community. While the ecology community is reinterpreting this theory, the reinterpretation has not been introduced into the molecular systems biology community that is studying the intersection of regulatory pathways. In this article, I describe evidence against a simple growth versus immunity tradeoff concept and propose an alternative wherein the intersection of these regulatory pathways is instead designed to coordinate these pathways, and not simply link them in mutual antagonism, to optimize fitness in complex environments where resistance/immunity and growth do not have simple linear relationships with fitness.

To prevent privacy leakage, cloud services need to take corresponding methods, so participants often face the dilemma of service utility and privacy protection. In this paper, we propose a dynamic adaptive access control model based on trust permission and privacy protection to solve the problem of privacy disclosure and utility in the cloud service. Firstly, we add the concept of obligation and purpose into access control and establish the privacy information tree and privacy policy tree. Secondly, we establish a new trust evaluation and give the corresponding weight algorithm. Thirdly, we quantify the privacy information with the normal space and correlation coefficient method. Further, we propose a tradeoff relationship model between trust permission and privacy protection, each participant can select the corresponding parameters according to the actual requirement and personal preference. Experimental analysis and comparison results verify the feasibility, effectiveness, and superiority of our method. Finally, we summarize the work of this paper and point out the future development direction.

Long-term excessive use of chemical fertilizer has led to water environmental degradation. Reducing chemical fertilizer use in crop production has become a consensus, and the effects of chemical fertilizer reduction on yield, water consumption and water environment urgently need to be explored. A field experiment including four fertilization treatments: normal fertilizer application (NFA), 15%, 30% and 45% fertilizer reduction (FR) was conducted and the water footprint (WF) was used as an indicator to explore how the chemical fertilizer reduction affected the maize WF. The results showed that the blue, green and total WFs of maize in the 45% FR and NFA treatments were larger than those in the 30% FR and 15% FR treatments in 2018 and 2019. The grey WFs of maize in the NFA treatment were the highest in 2018 and 2019, exhibiting a trend that the grey WFs in the NFA treatment >15% FR treatment >30% FR treatment >45% FR treatment in 2018 and those in the NFA treatment >45% FR treatment >30% FR treatment >15% FR treatment in 2019. The optimal treatment was the 15–30% FR compared with the current fertilization, in which the total WF of maize can be minimized and the maize yield can be maximized at the same time. Precipitation had a wide-ranging impact on the yield and WF of maize, especially the amount, intensity and interval of rainfall, which had an evident impact on the grey WF. This study is expected to provide a data foundation for reducing chemical fertilizer and improving water and fertilizer use efficiency in maize production. [ABSTRACT FROM AUTHOR]

Summary: Phytoplankton are responsible for nearly half of global primary productivity and play crucial roles in the Earth's biogeochemical cycles. However, the long‐term adaptive responses of phytoplankton to rising CO2 remains unknown.Here we examine the physiological and proteomics responses of a marine diatom, Phaeodactylum tricornutum, following long‐term (c. 900 generations) selection to high CO2 conditions.Our results show that this diatom responds to long‐term high CO2 selection by downregulating proteins involved in energy production (Calvin cycle, tricarboxylic acid cycle, glycolysis, oxidative pentose phosphate pathway), with a subsequent decrease in photosynthesis and respiration. Nearly similar extents of downregulation of photosynthesis and respiration allow the high CO2‐adapted populations to allocate the same fraction of carbon to growth, thereby maintaining their fitness during the long‐term high CO2 selection.These results indicate an important role of metabolism reduction under high CO2 and shed new light on the adaptive mechanisms of phytoplankton in response to climate change. [ABSTRACT FROM AUTHOR]

Background: For better understanding the mechanism of Reaumuria soongarica community formation in a salt stressed grassland ecosystem, we designed a field experiment to test how leaves salt secretion changes the competitive relationship between species in this plant communities. Results: Among the three species (R. soongarica, Stipa glareosa and Allium polyrhizum) of the salt stressed grassland ecosystem, the conductivity of R. soongarica rhizosphere soil was the highest in five soil layers (0–55 cm depth). The high soil conductivity can increase the daily salt secretion rate of plant leaves of R. soongarica. In addition, we found the canopy size of R. soongarica was positively related to the distance from S. glareosa or A. polyrhizum. The salt-tolerance of R. soongarica was significantly higher than the other two herbs (S. glareosa and A. polyrhizum). Moreover, there was a threshold (600 µS/cm) for interspecific competition of plants mediated by soil conductivity. When the soil conductivity was lower than 600 µS/cm, the relative biomass of R. soongarica increased with the soil conductivity increase. Conclusions: The efficient salt secretion ability of leaves increases soil conductivity under the canopy. This leads the formation of a "saline island" of R. soongarica. Meanwhile R. soongarica have stronger salt tolerance than S. glareosa and A. polyrhizum. These promote the competitiveness of R. soongarica and inhibit interspecies competition advantage of the other two herbs (S. glareosa and A. polyrhizum) in the plant community. It is beneficial for R. soongarica to establish dominant communities in saline regions of desert grassland. [ABSTRACT FROM AUTHOR]

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.

It has been shown that an evolutionary tradeoff between vertical (host growth rate) and horizontal (plasmid conjugation) transmissions contributes to global plasmid fitness. As conjugative IncC plasmids are important for the spread of multidrug resistance (MDR), in a broad range of bacterial hosts, we investigated vertical and horizontal transmissions of two multidrug-resistant IncC plasmids according to their backbones and MDR-region rearrangements, upon plasmid entry into a new host. We observed plasmid genome deletions after conjugation in three diverse natural Escherichia coli clinical strains, varying from null to high number depending on the plasmid, all occurring in the MDR region. The plasmid burden on bacterial fitness depended more on the strain background than on the structure of the MDR region, with deletions appearing to have no impact. Besides, we observed an increase in plasmid transfer rate, from ancestral host to new clinical recipient strains, when the IncC plasmid was rearranged. Finally, using a second set of conjugation experiments, we investigated the evolutionary tradeoff of the IncC plasmid during the critical period of plasmid establishment in E. coli K-12, by correlating the transfer rates of deleted or non-deleted IncC plasmids and their costs on the recipient strain. Plasmid deletions strongly improved conjugation efficiency with no negative growth effect. Our findings indicate that the flexibility of the MDR-region of the IncC plasmids can promote their dissemination, and provide diverse opportunities to capture new resistance genes. In a broader view, they suggest that the vertical-horizontal transmission tradeoff can be manipulated by the plasmid to improve its fitness., Competing Interests: The authors declare no conflict of interest.

Balancing erosion control and the water conservation service is the primary goal of intensive revegetation in water‐limited conditions. In this study, a field experiment was conducted in the dryland Chinese Loess Plateau (CLP), to investigate the role of vegetation pattern and density in their tradeoff between soil conservation (SC) and soil water retention (SWR). Five vegetation patterns (up‐slope covered, downslope covered, low and high uniformly covered, no coverage) with three levels of grass density (220 g m−2, 110 g m−2, and 0) were designed and implemented. A novel indicator EEW (the exchange between erosion reduction and water consumption), as the cost of any extra depletion of soil water to improve each unit of soil conservation, was used to represent the tradeoff during a complete dry‐wet‐dry soil water convert cycle. The higher EEW, the poorer tradeoff between SC and SWR. It was illustrated that higher vegetation density could promote SC but not inevitably suppress EEW. The present typical grass density in CLP, round 220 g m−2, was redundant in optimizing the SC‐SWR tradeoff. A concentrated and centralized vegetation distribution mainly in the downslope obtained an EEW at 11.6 mm m2 kg−1 and was confirmed as a favoured vegetation pattern. The simulated typical density and spatial pattern in CLP (about 220 g m−2 and uniformly distribution) had EEW at 20.5 mm m2 kg−1, by reducing the density to about 110 g m−2 and a downslope centralized vegetation redistribution, the EEW was reduced by 43.4%. Under long‐term drought conditions at dry‐wet‐dry cycles, soil water decreased more sharply in the Full‐covered plots, due to more evapotranspiration and vertical water loss caused by higher plant density, compared with half‐covered and bare soil plots. The present study confirmed that planted density and vegetation pattern can manipulate SC‐SWR tradeoff and it was thus possible to optimize it by adjusting revegetation's intensity and structures in practice. [ABSTRACT FROM AUTHOR]

It is well known that AM symbiosis provides several ecosystem services leading to plant adaptation in different environmental conditions and positively affects physiological and production features. Although beneficial effects from grapevine and AM fungi interactions have been reported, the impact on growth-defence tradeoff features has still to be elucidated. In this study, the potential benefits of an inoculum formed by two AM fungal species, with or without a monosaccharide addition, were evaluated on young grapevine cuttings grafted onto 1103P and SO4 rootstocks. Inoculated and non-inoculated plants were maintained in potted vineyard substrate under greenhouse conditions for 3 months. Here, agronomic features were combined with biochemical and molecular techniques to assess the influence of the different treatments. Despite the opposite behaviour of the two selected rootstocks, in AM samples, the evaluation of gene expression, agronomic traits and metabolites production revealed an involvement of the whole root microbiome in the growth-defence tradeoff balancing. Noteworthy, we showed that rootstock genotypes and treatments shaped the root-associated microbes, stimulating plant growth and defence pathways. Progresses in this field would open new perspectives, enabling the application of AMF or their inducers to achieve a more sustainable agriculture also in light of the ongoing climate change. [ABSTRACT FROM AUTHOR]

One of the today's greatest challenges is to adjust our behavior so that we can avoid a major climate disaster. To do so, we must make sacrifices for the sake of the environment. The study reported here investigates how anchors (extrinsic motivational-free information) and normative messages (extrinsic motivational information) influence people's tradeoffs between travel time and carbon dioxide (CO2) emissions in the context of car travel and whether any interactions with environmental concern (an intrinsic motivational factor) can be observed. In this study, people received either a CO2, health or no normative message together with either a high anchor, a low anchor, or no anchor. People that received both a high anchor and a CO2 emission normative message were willing to travel for a longer time than those that only received a high anchor. If a low anchor was presented, no differences in willingness to travel for a longer time were found between the three different conditions of normative message groups, i.e., CO2 normative message, health normative message, or no normative message. People with higher concern for the environment were found to be willing to travel for a longer time than those with lower concern for the environment. Further, this effect was strongest when a high anchor was presented. These results suggest that anchors and normative messages are among the many factors that can influence people's tradeoffs between CO2 emission and travel time, and that various factors may have to be combined to increase their influence over pro-environmental behavior and decisions. [ABSTRACT FROM AUTHOR]

We consider the single-machine scheduling problem to tradeoff between the number and the length of accepted jobs. The algorithm introduced by Lin and Wang (2007) (called Lin-Wang's algorithm), for solving the single-machine scheduling problem to minimize the number of tardy jobs, is closely related to our research. The original version of Lin-Wang's algorithm runs in O (n 2) time. By using the technique of the preemptive scheduling combined with a data structure, we show in this paper that a variant of Lin-Wang's algorithm actually runs in O (n log ⁡ n) time. This enables us to further show that the tradeoff problem can be solved in O (n log ⁡ n) time. [ABSTRACT FROM AUTHOR]

One of the today’s greatest challenges is to adjust our behavior so that we can avoid a major climate disaster. To do so, we must make sacrifices for the sake of the environment. The study reported here investigates how anchors (extrinsic motivational-free information) and normative messages (extrinsic motivational information) influence people’s tradeoffs between travel time and carbon dioxide (CO2) emissions in the context of car travel and whether any interactions with environmental concern (an intrinsic motivational factor) can be observed. In this study, people received either a CO2, health or no normative message together with either a high anchor, a low anchor, or no anchor. People that received both a high anchor and a CO2 emission normative message were willing to travel for a longer time than those that only received a high anchor. If a low anchor was presented, no differences in willingness to travel for a longer time were found between the three different conditions of normative message groups, i.e., CO2 normative message, health normative message, or no normative message. People with higher concern for the environment were found to be willing to travel for a longer time than those with lower concern for the environment. Further, this effect was strongest when a high anchor was presented. These results suggest that anchors and normative messages are among the many factors that can influence people’s tradeoffs between CO2 emission and travel time, and that various factors may have to be combined to increase their influence over pro-environmental behavior and decisions.

In cooperative systems exhibiting division of labor, such as microbial communities, multicellular organisms, and social insect colonies, individual units share costs and benefits through both task specialization and exchanged materials. Socially exchanged fluids, like seminal fluid and milk, allow individuals to molecularly influence conspecifics. Many social insects have a social circulatory system, where food and endogenously produced molecules are transferred mouth-to-mouth (stomodeal trophallaxis), connecting all the individuals in the society. To understand how these endogenous molecules relate to colony life, we used quantitative proteomics to investigate the trophallactic fluid within colonies of the carpenter ant Camponotus floridanus. We show that different stages of the colony life cycle circulate different types of proteins: young colonies prioritize direct carbohydrate processing; mature colonies prioritize accumulation and transmission of stored resources. Further, colonies circulate proteins implicated in oxidative stress, ageing, and social insect caste determination, potentially acting as superorganismal hormones. Brood-caring individuals that are also closer to the queen in the social network (nurses) showed higher abundance of oxidative stress-related proteins. Thus, trophallaxis behavior could provide a mechanism for distributed metabolism in social insect societies. The ability to thoroughly analyze the materials exchanged between cooperative units makes social insect colonies useful models to understand the evolution and consequences of metabolic division of labor at other scales.

This article presents a model-based hybrid adaptive dynamic programming (ADP) framework consisting of continuous feedback-based policy evaluation and policy improvement steps as well as an intermittent policy implementation procedure. This results in an intermittent ADP with a quantifiable performance and guaranteed closed-loop stability of the equilibrium point. To investigate the effect of aperiodic sampling on the communication bandwidth and the control performance of the intermittent ADP algorithms, we use a Hamiltonian-driven unified framework. With such a framework, it is shown that there is a tradeoff between the communication burden and the control performance. We finally show that the developed policies exhibit Zeno-free behaviors. Simulation examples show the efficiency of the proposed framework along with quantifiable comparisons of the policies with different intermittent information. [ABSTRACT FROM AUTHOR]

Water management usually considers economic and ecological objectives, and involves tradeoffs, conflicts, compromise, and cooperation among objectives. Pareto optimality often is championed in water management, but its relationships with the mathematical representation of objectives, and implications of tradeoffs for Pareto optimal decisions, are rarely examined. We evaluate the mathematical properties of optimized tradeoffs to identify promising regions for compromise, suggest strategies for reducing conflicts, and better understand whether decision‐makers are more or less likely to cooperate on environmental water allocations. Cooperation and compromise among objectives can be easier when tradeoff curves are concave and more adversarial when tradeoff curves are convex. "Knees," or areas with maximum curvature, bulges, or breakpoints in concave Pareto frontiers, suggest more promising areas for compromise. Evaluating the shape of Pareto curves based on each objective's performance function can screen for the existence of knees amenable to compromise. We explore water management and restorations actions that improve and shift the location and prominence of knees in concave Pareto frontiers. Connecting river habitats and other non‐flow management actions may add knees on locally concave regions of Pareto frontiers. Managing multiple streams regionally, rather than individually, can sometimes turn convex local tradeoffs into concave regional tradeoffs more amenable to compromise. Overall, this analysis provides a deep investigation of how the shape of tradeoffs influences the range and promise of decisions to improve performance, and illustrates that management actions may encourage cooperation and reduce conflict. Plain Language Summary: Water management usually considers economic and ecological objectives, and involves tradeoffs, conflicts, compromise, and cooperation among objectives. We evaluate the mathematical properties of tradeoffs to identify promising regions for compromise, suggest strategies for reducing conflicts, and better understand whether decision‐makers are more or less likely to cooperate on environmental water allocations. Cooperation and compromise among objectives can be easier when tradeoff curves are concave and more adversarial when tradeoff curves are convex. "Knees", or areas with maximum curvature, bulges, or breakpoints in concave tradeoffs, suggest more promising areas for compromise. We explore water management and restorations actions that improve and shift the location and prominence of knees in concave tradeoff curves. Connecting river habitats and other non‐flow management actions may add knees on locally concave regions of tradeoffs curves. Managing multiple streams regionally, rather than individually, can sometimes turn convex local tradeoffs into concave regional tradeoffs more amenable to compromise. Overall, this analysis provides an investigation of how the shape of tradeoffs influences the range and promise of decisions to improve performance, and illustrates that management actions may encourage cooperation and reduce conflict. Key Points: The shape of the Pareto frontier influences whether decision‐makers are more or less likely to cooperate over environmental water allocationsCompromise is more likely where knees, or areas of maximum curvature, occur in concave tradeoff frontiersManagement actions, like non‐flow improvements to objectives can expand the Pareto curve and improve optima for one or both objectives [ABSTRACT FROM AUTHOR]

This paper focuses on the QoS-aware secure routing design based on the physical layer security technology for a multi-hop wireless network consisting of legitimate nodes, malicious eavesdroppers, and selfish jammers. We first provide theoretical modeling for a given route to reveal how its end-to-end security/QoS performance is related to the transmitting power of legitimate nodes along the route and the jamming power of jammers in the network. We then design an incentive mechanism that stimulates jammers to generate artificial jamming for security enhancement, and also develop a non-cooperative game framework to resolve the jamming power setting issue here. Based on the security/QoS performance modeling of the route and jamming power setting, we further propose a theoretical framework to determine the optimal transmitting power of nodes along the route such that its optimal transmission security can be achieved under a QoS constraint. Finally, with the help of the power setting results of the given route, we formulate a shortest weighted path-finding problem to identify the optimal route for data delivery in the network, which can be solved by employing the Bellman-Ford or Dijkstra’s algorithm. It is demonstrated that the proposed routing scheme is individually rational, stable, distributed and computationally efficient. [ABSTRACT FROM AUTHOR]

Industrial Control Systems (ICS) security happens often, which makes it hard for many organizations to keep a balance between operational efficiency, system efficiency, and security. A major concern is how to protect information security and make sure that ICS keep working. This study thus presents a defense-based system with adaptive cyber resilience (DSACR). DSACR will optimize the configuration with respect to the three indices of operational efficiency, performance, and security. Whenever an assault event happens, DSACR offers protective solutions depending on the threat level to optimize the security and running costs of recovering ICS. In terms of safety and operation, DSACR is superior to other approaches by 3 % and 11 %, respectively, as shown by the results of the experiments. [ABSTRACT FROM AUTHOR]

The performances of heuristic algorithms are highly dependent on the parameters used, and usually difficult to determine subjectively. Thus, how to balance the relations between the qualities of the solutions and the values of the parameters has been a hot and lasting topic in the field of optimization research. This article presented a statistical method to estimate the efficient parameter values of three alternative neighborhood search techniques of simulated annealing when applied to forest spatial harvest scheduling problems, as an example. The neighborhood search techniques included: the conventional version of simulated annealing (Method1), and the swapping version (Method2) and the changing version (Method3) of 2-element optimization (2-opt) moves. Results indicated that the performances of different neighborhood search strategies highly depended on the problem size, in which the superiorities of Method2 increased from about 10% for smaller cases (400 units) to approximately 80% of larger cases (>3600 units) when compared the objective function values with Method1 and Method3. The efficient parameter values of the cooling rate (CR), the number of iterations per temperature (Ntem), and the number of iterations used for generating initial solution (Nsol) could be estimated using polynomial functions with the number of units, while the initial temperature (IT) should be estimated using exponential function, where the determination coefficient ($R^{2}$ ) of the fitted functions were all larger than 0.60 [except for Nsol and CR of Mehod1 ($R^{2}=0.32$ and 0.42), CR of Method2 ($R^{2}=0.20$ )]. The number of satisfactory solutions all increased linearly ($R^{2} > 0.85$ ) with the number of units, while the solution efficiency decreased linearly ($R^{2} > 0.30$ ). The verifications of two extra grid datasets indicated that the parameter optimization methods were valid.

Large amounts of carbon are required for plant growth, but young, growing tissues often also have high concentrations of defensive secondary metabolites. Plants' capacity to allocate resources to growth and defense is addressed by the growth-differentiation balance hypothesis and the optimal defense hypothesis, which make contrasting predictions. Isotope labeling can demonstrate whether defense compounds are synthesized from stored or newly fixed carbon, allowing a detailed examination of these hypotheses. Populus trichocarpa saplings were pulse-labeled with 13CO2 at the beginning and end of a growing season, and the 13C signatures of phenolic glycosides (salicinoids), sugars, bulk tissue, and respired CO2 were traced over time. Half of the saplings were also subjected to mechanical damage. Populus trichocarpa followed an optimal defense strategy, investing 13C in salicinoids in expanding leaves directly after labeling. Salicinoids turned over quickly, and their production continued throughout the season. Salicin was induced by early-season damage, further demonstrating optimal defense. Salicinoids appear to be of great value to P. trichocarpa, as they command new C both early and late in the growing season, but their fitness benefits require further study. Export of salicinoids between tissues and biochemical pathways enabling induction also needs research. Nonetheless, the investigation of defense production afforded by isotope labeling lends new insights into plants' ability to grow and defend simultaneously.

Premise: Across taxa, vegetative and floral traits that vary along a fast‐slow life‐history axis are often correlated with leaf functional traits arrayed along the leaf economics spectrum, suggesting a constrained set of adaptive trait combinations. Such broad‐scale convergence may arise from genetic constraints imposed by pleiotropy (or tight linkage) within species, or from natural selection alone. Understanding the genetic basis of trait syndromes and their components is key to distinguishing these alternatives and predicting evolution in novel environments. Methods: We used a line‐cross approach and quantitative trait locus (QTL) mapping to characterize the genetic basis of twenty leaf functional/physiological, life history, and floral traits in hybrids between annualized and perennial populations of scarlet monkeyflower (Mimulus cardinalis). Results: We mapped both single and multi‐trait QTLs for life history, leaf function and reproductive traits, but found no evidence of genetic co‐ordination across categories. A major QTL for three leaf functional traits (thickness, photosynthetic rate, and stomatal resistance) suggests that a simple shift in leaf anatomy may be key to adaptation to seasonally dry habitats. Conclusions: Our results suggest that the co‐ordination of resource‐acquisitive leaf physiological traits with a fast life‐history and more selfing mating system results from environmental selection rather than functional or genetic constraint. Independent assortment of distinct trait modules, as well as a simple genetic basis to leaf physiological traits associated with drought escape, may facilitate adaptation to changing climates. [ABSTRACT FROM AUTHOR]

In a fault-tolerant Distributed Storage System (DSS) that depends on regenerating codes, there may be a variety of motivations for the system or the user to switch from one set of code parameters (n, k, d, α, β) to another. For example, the user may change their demand on reliability or the system may want to change the configuration due to implementation challenges, cost considerations and issues related to availability/ accessibility of geographically-distributed nodes. This can be managed by a well-designed DSS capable of dynamically scaling the parameters. In this letter, we present lower bounds on the bandwidth requirements for moving from a regenerating code configuration to another. In case of functional repair, our lower bounds are achievable, which helps the system designers identify the minimum-cost scaling strategy. [ABSTRACT FROM AUTHOR]

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Huanglongbing (HLB) is the most destructive citrus disease worldwide. This is associated with the phloem-limited bacterium Candidatus Liberibacter, and the typical symptom is leaf blotchy mottle. To better understand the biological processes involved in the establishment of HLB disease symptoms, the comparative proteomic analysis was performed to reveal the global protein accumulation profiles in leaf petiole, where there are massive HLB pathogens of Ca. L. asiaticus-infected Newhall sweet orange (Citrus sinensis) plants at the asymptomatic and symptomatic stages compared to their healthy counterpart. Photosynthesis, especially the pathway involved in the photosystem I and II light reactions, was shown to be suppressed throughout the whole Ca. L. asiaticus infection cycle. Also, starch biosynthesis was induced after the symptom-free prodromal period. Many defense-associated proteins were more extensively regulated in the petiole with the symptoms than the ones from healthy plants. The change of salicylic and jasmonic acid levels in different disease stages had a positive correlation with the abundance of phytohormone biosynthesis-related proteins. Moreover, the protein–protein interaction network analysis indicated that an F-type ATPase and an alpha-1,4 glucan phosphorylase were the core nodes in the interactions of differentially accumulated proteins. Our study indicated that the infected citrus plants probably activated the non-unified and lagging enhancement of defense responses against Ca. L. asiaticus at the expense of photosynthesis and contribute to find out the key Ca. L. asiaticus-responsive genes for tolerance and resistance breeding.

Huanglongbing (HLB) is the most destructive citrus disease worldwide. This is associated with the phloem-limited bacterium Candidatus Liberibacter, and the typical symptom is leaf blotchy mottle. To better understand the biological processes involved in the establishment of HLB disease symptoms, the comparative proteomic analysis was performed to reveal the global protein accumulation profiles in leaf petiole, where there are massive HLB pathogens of Ca. L. asiaticus-infected Newhall sweet orange (Citrus sinensis) plants at the asymptomatic and symptomatic stages compared to their healthy counterpart. Photosynthesis, especially the pathway involved in the photosystem I and II light reactions, was shown to be suppressed throughout the whole Ca. L. asiaticus infection cycle. Also, starch biosynthesis was induced after the symptom-free prodromal period. Many defense-associated proteins were more extensively regulated in the petiole with the symptoms than the ones from healthy plants. The change of salicylic and jasmonic acid levels in different disease stages had a positive correlation with the abundance of phytohormone biosynthesis-related proteins. Moreover, the protein–protein interaction network analysis indicated that an F-type ATPase and an alpha-1,4 glucan phosphorylase were the core nodes in the interactions of differentially accumulated proteins. Our study indicated that the infected citrus plants probably activated the non-unified and lagging enhancement of defense responses against Ca. L. asiaticus at the expense of photosynthesis and contribute to find out the key Ca. L. asiaticus-responsive genes for tolerance and resistance breeding. [ABSTRACT FROM AUTHOR]

Multi‐infections may result in either competitive exclusion or coexistence on the same host of pathogen genotypes belonging to the same or different species. Epidemiological consequences of multiple infections, particularly how the development and transmission of a pathogen can be modified by the presence of another pathogen, are well documented. However, understanding how life history strategies of each pathogen modulate co‐infection outcomes remains quite elusive. To analyze how co‐infection drives changes in life history traits and affects co‐existence in epidemic pathogens, we infected detached pea stipules with two fungal species, Peyronellaea pinodes and Phoma medicaginis var. pinodella (considering two strains per species), part of the ascochyta blight complex but presenting different life history strategies. All pairwise combinations (including self‐pairs) between two strains of each species were tested. Strains were inoculated simultaneously, but apart from one another on the stipule. For each strain, four life history traits were measured: incubation period, necrosis area six days after inoculation, latent period and offspring production. Results show that, in co‐infection, when resources are highly allocated to lesion development, the time between inoculation and the appearance of reproduction structures (latent period) and offspring production decreased, and vice‐versa relative to single infections. The direction and/or magnitude of these responses to co‐infection depend on the co‐infecting strains. Moreover, these changes were always higher in self‐pairs than in mixed co‐infections. These results suggest facilitation between co‐infecting strains, resulting in the selection of an intermediate level of virulence (here measured as the lesion development) at the expense of pathogen offspring production. This strategy allows the development and reproduction of each co‐infecting strain when sharing limited resources. However, the direction and strength of these life history traits variations in co‐infection depend on the life history strategy of the co‐infecting strains, with a clear difference between 'opportunists', 'scavengers' and 'pioneer colonisers'. [ABSTRACT FROM AUTHOR]

Understanding how individual tradeoffs and carry‐over effects along the annual cycle influence fitness is fundamental to unravel population dynamics, but such data is particularly challenging to collect in long‐distance migrants. Here, with a full annual cycle perspective of Icelandic whimbrels Numenius phaeopus islandicus, we investigate tradeoffs across the entire distribution, assessing migration costs and wintering energetic balance experienced throughout the wintering range (from temperate to tropical regions), and link these to breeding parameters for two wintering regions. We found that Icelandic whimbrels traded off higher costs of migration with more favourable wintering conditions, in terms of energetic balance. By migrating further, whimbrels experience lower thermoregulatory costs and higher net energetic intake rates, resulting in a more positive energetic balance during winter. However, these differences did not appear to carry‐over into the breeding season in terms of measurable effects on laying date (and, consequently, fledging success) or egg volume, suggesting that individual fitness is unlikely to be significantly influenced by previous wintering conditions, although effects on other traits may potentially occur. Nevertheless, Icelandic whimbrels seem to favour wintering locations where the conditions are more advantageous, as the abundance of individuals at the wintering sites reflects the variation in site quality. [ABSTRACT FROM AUTHOR]

Organisms face tradeoffs in performing multiple tasks. Identifying the optimal phenotypes maximizing the organismal fitness (or Pareto front) and inferring the relevant tasks allow testing phenotypic adaptations and help delineate evolutionary constraints, tradeoffs, and critical fitness components, so are of broad interest. It has been proposed that Pareto fronts can be identified from high-dimensional phenotypic data, including molecular phenotypes such as gene expression levels, by fitting polytopes (lines, triangles, tetrahedrons, and so on), and a program named ParTI was recently introduced for this purpose. ParTI has identified Pareto fronts and inferred phenotypes best for individual tasks (or archetypes) from numerous data sets such as the beak morphologies of Darwin's finches and mRNA concentrations in human tumors, implying evolutionary optimizations of the involved traits. Nevertheless, the reliabilities of these findings are unknown. Using real and simulated data that lack evolutionary optimization, we here report extremely high false-positive rates of ParTI. The errors arise from phylogenetic relationships or population structures of the organisms analyzed and the flexibility of data analysis in ParTI that is equivalent to p -hacking. Because these problems are virtually universal, our findings cast doubt on almost all ParTI-based results and suggest that reliably identifying Pareto fronts and archetypes from high-dimensional phenotypic data are currently generally difficult. [ABSTRACT FROM AUTHOR]

Both inter‐ and intraspecific trait variation are critical to species distribution along environmental gradients, but our understanding of these patterns predominantly relies upon species‐level trait means and variances. Trait integration, defined as how strongly multiple traits covary with one another, is a key indicator of the dimensionality of functional space for accommodating biodiversity in communities. As trait covariance can differ dramatically at the interspecific versus intraspecific levels, how intraspecific trait variability alters the strength of trait integration and eventually modulates biodiversity along environmental gradients has been rarely tested. Here, we measured nine functional traits (leaf area, specific leaf area, leaf and stem dry‐matter content, leaf nitrogen and phosphorus contents, specific stem length, Huber value and maximum height) paired with site‐specific soil fertility for 70 woody communities in subtropical Chinese forests. All species‐by‐site combinations were sampled to ensure a sufficient representation of intraspecific trait variation across sites. Community‐level trait integration was quantified from the variance of eigenvalues of the trait correlation matrix. The direct and/or indirect effects of soil fertility and trait integration on species richness and trait diversity were assessed through path analyses. Trait integration quantified from both inter‐ and intraspecific variances was on average 21.7% weaker than that from only interspecific variance, indicating a crucial role of intraspecific trait variability in promoting niche dimensionality. Whether accounting for intraspecific variation or not, less fertile sites had stronger trait integration, which in turn depressed both taxonomic and functional diversity, supporting the assumption that higher environmental stress demands stronger tradeoffs among multiple functions in viable strategies. Importantly, the negative association between trait integration and species richness became stronger when accounting for intraspecific variation, suggesting that species distribution and occurrence can be a consequence of intraspecific trait variability. This study highlights the importance of intraspecific trait variability in understanding functional tradeoffs underlying biodiversity patterns. [ABSTRACT FROM AUTHOR]

Colorful sexual traits are shaped by the opposing pressures of natural and sexual selection. Although increased conspicuousness improves mating success, an individual bearing brighter sexual traits may pay direct costs in terms of detectability to predators. While it is well established that the mere presence of non-aposematic, conspicuous sexual traits influences predation risk, little empirical work has examined how within-sex variability in sexual trait coloration affects attack rates; of these studies, results are equivocal. We experimentally tested the hypothesis that, within a single sex, brighter sexually selected traits impose a greater survival risk. We created clay models resembling male water anoles (Anolis aquaticus) and manipulated the coloration (bright red vs. brown-orange) of their colorful sexual ornament, the dewlap. Models were placed and monitored within A. aquaticus habitat. Our results suggest that a more conspicuous dewlap coloration is a cause of increased attack: redder models were attacked more than twice as often as less red models. Although previous studies have found correlational relationships between conspicuous coloration and predation, or have demonstrated long-term evolutionary changes in sexual dichromatism caused by a change in predator regime, our results show direct, within-lifetime costs of conspicuous sexual coloration among individuals of the same sex. These findings correspond well with a contemporary understanding of the drivers of female choice for costly male traits. These results also suggest the need for additional study on the effects of predation on the evolution of intrasexual variation in colorful sexual traits. [ABSTRACT FROM AUTHOR]

Robustness is the reproducible development of a phenotype despite stochastic noise. It often involves tradeoffs with other performance metrics, but the mechanisms underlying such tradeoffs were largely unknown. An Arabidopsis flower robustly develops four sepals from four precisely positioned auxin maxima. The development related myb-like 1 ( drmy1) mutant generates noise in auxin signaling that disrupts robustness in sepal initiation. Here, we found that increased expression of CUP-SHAPED COTYLEDON1 ( CUC1 ), a boundary specification transcription factor, in drmy1 underlies this loss of robustness. CUC1 surrounds and amplifies stochastic auxin noise in drmy1 to form variably positioned auxin maxima and sepal primordia. Removing CUC1 from drmy1 provides time for noisy auxin signaling to resolve into four precisely positioned auxin maxima, restoring robust sepal initiation. However, removing CUC1 decreases auxin maxima intensity and slows down sepal initiation. Thus, CUC1 increases morphogenesis speed but impairs robustness against auxin noise. Further, using a computational model, we found that the observed phenotype can be explained by the effect of CUC1 in repolarizing PIN FORMED1 (PIN1), a polar auxin transporter. Lastly, our model predicts that reducing global growth rate improves developmental robustness, which we validated experimentally. Thus, our study illustrates a tradeoff between speed and robustness during development., Competing Interests: COMPETING INTERESTS The authors declare no competing interests.

Fitness effects of mutations depend on environmental parameters. For example, mutations that increase fitness of bacteria at high antibiotic concentration often decrease fitness in the absence of antibiotic, exemplifying a tradeoff between adaptation to environmental extremes. We develop a mathematical model for fitness landscapes generated by such tradeoffs, based on experiments that determine the antibiotic dose-response curves of Escherichia coli strains, and previous observations on antibiotic resistance mutations. Our model generates a succession of landscapes with predictable properties as antibiotic concentration is varied. The landscape is nearly smooth at low and high concentrations, but the tradeoff induces a high ruggedness at intermediate antibiotic concentrations. Despite this high ruggedness, however, all the fitness maxima in the landscapes are evolutionarily accessible from the wild type. This implies that selection for antibiotic resistance in multiple mutational steps is relatively facile despite the complexity of the underlying landscape.

Promoting cloud services must consider the privacy requirements between the user and the provider. Both privacy and trust are related to knowledge about an entity; however, there is an inherent conflict between trust and privacy. In this paper, we research the relationship between privacy and trust in the cloud computing. First, we construct a trust model based on multiple factors, such as direct trust, trust risk, reward-punishment, and feedback trust; the weight of trust factor is determined by class diversity and information entropy theory. Second, we propose a novel privacy metric model with multiple factors, such as privacy preference, credential attribute, interaction history, and privacy feedback, and the weight of privacy factor is based on the maximum dispersion. Third, we propose a tradeoff between privacy and trust; both user and the provider can choose privacy protection or trust establishment priority by personal preference and requirement. Fourth, we demonstrate and compare the tradeoff between privacy and trust, interaction success rate, trust evaluation accuracy, and privacy disclosure rate by different experiments; these simulation results show that the privacy of each partner can be effectively protected.

In this paper, we consider an unmanned aerial vehicle (UAV)-enabled wireless-powered communication network (WPCN), where a rotary-wing UAV is employed as a hybrid access point (AP) to serve multiple ground users (GUs). Specifically, the GUs harvest radio frequency (RF) energy from the signal sent by the UAV, which is then used by the GUs to power their uplink information transmission to the UAV. In practice, the mission completion time and energy consumption are two important indexes to evaluate the performance of UAV-enabled communication. To complete the mission as soon as possible, the UAV should fly above the ground users it serves at maximum speed, but this leads to more propulsion energy being consumed. Our objective is to reveal the energy-time tradeoff, characterized by the boundary of the so-called “Energy-Time” region. We first derive the mathematical form of the tradeoff, the UAV trajectory, user scheduling and mission completion time, as well as the time allocation, all of which need to be jointly optimized. To this end, we propose two communication protocols: (i) fly-hover-communicate and (ii) path discretization. For each protocol, we first find the two extremes, where minimum energy consumption and minimum mission completion time are achieved. We then complete the boundary for minimizing the energy consumption for given mission completion time. Moreover, because of the nonconvexity of the problem, we propose an algorithm to obtain a locally optimal solution based on the successive convex approximation (SCA) technique for both designs. Finally, the simulation results are provided to validate the effectiveness of our study.

An optimal fault detection (FD) approach for a class of networked control systems (NCSs) is concerned in this work. To improve the accuracy of the FD, a new event-triggered scheme (ETS) is addressed, where the output measurement transmitted or not is determined by a set of conditions instead of a single condition. Moreover, output measurements in these conditions are not only the last transmitted data, but also the data in the past period of time. The structure of fault detection and isolation (FDI) consisting of the residual generation and residual evaluation can detect faults as accurately as possible, and show robustness to disturbances in the meantime. Optimal observer gains can be obtained by utilizing the discrete-time Riccati equation (DTRE), and the time-varying threshold can be specified by employing the linear matrix inequality (LMI). Finally, a numerical simulation and the application on closed-loop continuous stirred-tank reactor (CSTR) are adopted to prove the superiority of the proposed approach.

The need for particular software non-functional requirements (NFRs) leads a project team to use specific design strategies to fulfill these NFRs. However, some of the strategies may cause deficiencies in other software NFRs. These strategies are called conflicting strategies. Making the tradeoff decision of these conflicting strategies for NFRs is crucial. Therefore, a conflicting NFRs tradeoff framework (CNTF) and the corresponding method are proposed. Firstly, the NFRs are obtained from stakeholders. Fuzzy set theory is used to express stakeholder assessments on the importance of each NFR. The assessment results are ranked using a fuzzy ranking method. Then, adapting from production theory in microeconomics, the degree of satisfaction by which NFRs are affected by conflicting strategies are plotted as tradeoff curves. Borrowing the concept from the linear programming in management science, a tradeoff method is presented to help software project teams make the best tradeoff decision for conflicting NFRs. Finally, feasibility and limitations of the CNTF are elaborated in a case study.

Abstract As more and more mobile video applications contain important and private video data, various video encryption techniques have been proposed to protect them. Many of those applications typically utilize the standard video compression while running on mobile platforms which have limited amount of resources. Therefore, we need to consider not only the protection but also the compression and the energy in the mobile video applications. Accordingly, the selective video encryption which protects partial data within the standard video compression has been challenging thanks to format compliance and low computational complexity. However, various parameters of the video compression and the video encryption result in different amount of visual security, compression efficiency, and energy efficiency. Further, it is difficult to find the one solution to maximize all those performance indices at once since there exist tradeoff relationships among them. Therefore, based on the tradeoff relationships, design space exploration should be required to find the interesting parameter set under the given requirements. For the efficient design space exploration, we propose the BEVS (bitrate and energy-bound visual security) to examine each Joint Video Compression and Encryption scheme in terms of the visual security, the compression efficiency, and the energy efficiency. Utilizing the proposed BEVS in our experimental design space, we achieve up to 36.7% visual security improvement under the empirical budgets.

The performance of artificial nanomotors is still far behind nature-made biomolecular motors. A mechanistic disparity between the two categories exists: artificial motors often rely on a single mechanism to rectify directional motion, but biomotors integrate multiple mechanisms for better performance. This study proposes a design for a motor-track system and shows that by introducing asymmetric compound foot-track interactions, both selective foot detachment and biased foot-track binding arise from the mechanics of the system. The two mechanisms are naturally integrated to promote the motility of the motor towards being unidirectional, while each mechanism alone only achieves 50% directional fidelity at most. Based on a reported theory, the optimization of the motor is conducted via maximizing the directional fidelity. Along the optimization, the directional fidelity of the motor is raised by parameters that concentrate more energy on driving selective-foot detachment and biased binding, which in turn promotes work production due to the two energies converting to work via a load attached. However, the speed of the motor can drop significantly after the optimization because of energetic competition between speed and directional fidelity, which causes a speed-directional fidelity tradeoff. As a case study, these results test thermodynamic correlation between the performances of a motor and suggest that directional fidelity is an important quantity for motor optimization.

Abstract Background The purpose was to develop and test a population health measure that combines mean health outcomes and inequalities into a single GDP-like metric to help policymakers measure population health performance on both dimensions in one metric. Methods The Population Health Performance Index is a weighted average of a mean index and an inequality index according to the user’s inequality aversion. We deploy this methodology for two combinations of health outcome and disparity domain: infant mortality by race and unhealthy days by education. Results The PHPI is bounded between 0 and 1, and is comprised of a weighted average of two separate indices: a mean index and an inequality index, with 1 representing the ideal state of no ill health and no inequality and 0 representing the worst state in the U.S. PHPI values across states (neutral 50:50 weighting) vary between 0.60 (Massachusetts) to 0.17 (Delaware) for infant mortality by race and between 0.65 (North Dakota) to 0.00 (West Virginia) for unhealthy days by education. For some states, the choice of inequality aversion significantly impacts their PHPI value and state rank. Conclusions Mean and inequality health outcomes can be combined into a single Population Health Performance Index for use by public and private policy makers, like the GDP is used as a summary metric to measure economic output. The index can allow for varying degrees of inequality aversion, an individual’s or jurisdiction’s value choice that can substantially impact the value of this new summary population health metric.

Carbon sequestration and water conservation are two of the key ecosystem services that forests provide for societal need to address environmental issues. Optimization of the dual services is the ultimate goal in forest management for mitigating global climate change and safeguarding terrestrial water balance. However, there are some tradeoffs between gain in forest productivity and ecosystem water balance. We conducted literature review based on published articles for learned knowledge on forest carbon fixation and hydrological regulations. Some knowledge gaps and research needs are identified by examining the inter-connections between forest carbon sequestration and water conservation. Past researches have helped gain basic understanding of the mechanisms and controls of forest carbon fixation and hydrological regulations as two separate issues. Tools and approaches are well established for quantifying and monitoring forest carbon and hydrological issues, operating at different spatial and temporal scales. There are knowledge gaps on how to design afforestation schemes facilitating enhanced ecosystem services in forest carbon sequestration and water conservation. For the top-down planning of afforestation in regions where water availability is anticipated to be problematic, the questions of how much and where to plant for given land availability, known environmental implications, and sustained regional development and livelihood need to be addressed. For local management considerations, the questions of what and how to plant prevail. Efforts are needed in joint studies of forest carbon sequestration and water conservation functionalities, specifically in relation to establishment and management of planted forests aiming for delivering regulatory ecosystem services in carbon sequestration, water conservation and other social values. We propose an integrated framework with dual consideration of carbon sequestration and water conservation in forest management for future research pursue. [ABSTRACT FROM AUTHOR]

A tradeoff between forage acquisition and predation avoidance contributes to shape space use by herbivores. The manipulation of structural components of the habitat, such as forage and forest cover may alter this tradeoff. The idea of influencing space use of herbivores is appealing for wildlife managers that aim to locally modify herbivore densities and increase their vulnerability to hunting. We attempted to manipulate the tradeoff between forage acquisition and risk avoidance of white-tailed deer Odocoileus virginianus on Anticosti Island (Québec, Canada) using experimental hunting fields varying in forage production (fertilized or unfertilized fields) and residual forest cover (30 or 60-m-wide forested strips between fields). In this system with high deer density, no natural predator and limited forage, fecal group surveys and camera traps demonstrated greater use of fertilized fields. Residual forest cover did not impact habitat use, suggesting that use of the experimental fields was mainly driven by the benefits of foraging compared to the costs of avoiding hunters. Deer vulnerability to hunting, however, differed with residual forest cover: hunters saw more deer per hour in fields separated by 30-m-wide forested strips compared to fields separated by 60-m-wide forested strips. That hunters did not detect the difference in deer use between fertilized and unfertilized fields suggests that deer vulnerability to hunting and deer use could be modified by different structural components of the habitat. Our results provide useful insights for wildlife managers that have to deal with conflicting goals such as maintaining hunter satisfaction with high observation rates of deer while reducing the negative impacts of high deer densities on their body condition and, on the composition and structure of forests. [ABSTRACT FROM AUTHOR]

Plant breeding has improved traits such as fruit flavor and yield but may have compromised direct and indirect defenses to herbivores compared to their wild ancestors. This has been termed the plant domestication-reduced defense hypothesis. We present evidence that domestication of Capsicum annuum (the chili pepper) from its wild progenitor, Capsicum annuum var. glabriusculum, has not affected resistance to the insect herbivore, Manduca sexta (the tobacco hornworm). Caterpillars performed equally well on the domesticated and wild pepper. Subsequent behavioral choice assays with one of the main natural enemies of M. sexta, the parasitoid wasp Cotesia congregata, showed that parasitoids preferentially chose herbivore-damaged domesticated pepper plants over their wild relative. To investigate this tri-trophic interaction further, we then assessed the efficiency of C. congregata to parasitize M. sexta on numerous wild pepper accessions and domesticated pepper cultivars in a large foraging enclosure. We found that herbivores feeding on domesticated plants were parasitized at more than twice the rate of those on wild genotypes. These results imply that pepper domestication has not changed resistance to herbivorous insects (i.e., leaf palatability as a direct defense), but rather has improved volatile attraction to recruit natural enemies. [ABSTRACT FROM AUTHOR]

Magnetic resonant wireless power transfer (MR-WPT) has become a significant method for powering the measurement units in landslide monitoring boreholes. This paper focuses on the effects of quality factor, coupling distance and load on the power transfer stability, sensitivity and performance of an MR-WPT system. Firstly, through a numerical model of an MR-WPT, the effect of quality factor and coupling distance on the output power, transfer efficiency and frequency splitting phenomenon of MR-WPT systems have been comparatively analyzed. The relationship between the load and the coupling distance region corresponding to optimal transfer performance has been studied. Results show that improving the quality factor of the coils is beneficial for the transfer performance and stability of WPT system. Furthermore, through the selection of the load, a coupling distance region with high transfer stability and an optimal tradeoff between power and efficiency can be obtained. Finally, the above theoretical simulation results have been verified by experimental results. [ABSTRACT FROM AUTHOR]