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International audience; In order to capture the environmental externalities of urban agglomeration, we use an agglomeration indicator referred to as economic density, which can be decomposed into the average population density and the concentration of population distribution. Our benchmark regressions use the ordinary least squares method and grid-level panel data for China and for the period 2000–2016. We find that economic density is positively correlated with PM2.5 concentration, and the effects of the two components of economic density are opposite. To address the endogeneity issues, the causal effect of economic density on PM2.5 concentration is estimated with an instrumental variable method. Empirical results show that the PM2.5 concentration increases with economic density, and the associated elasticity is between 0.045 and 0.079. The findings of our benchmark regressions are also supported by a variety of robustness checks. Moreover, while economic growth, the development of secondary industry, and the presence of coal-driven power plants explain why cities with more dense population are more polluted, residential energy use is an opposite channel through which cities with higher economic density can reduce air pollution. Overall, the total effect is a trade-off, and the negative environmental externalities of agglomeration are larger than positive environmental externalities.

The immune response represents a suite of evolved traits that can involve energetic and evolutionary trade-offs with other energy-demanding and fitness-related processes. Here, we tested the hypothesis that aquatic beetles living in inland hypersaline habitats have lower immune capacity than freshwater congeners. Phenoloxidase activity, encapsulation response and antimicrobial peptide activity were compared in freshwater/hypersaline species pairs with differing osmoregulatory capacity and cuticular waterproofing properties in the genera Nebrioporus (Dytiscidae) and Enochrus (Hydrophilidae), independent evolutionary lineages that have colonised saline media separately. Hypersaline species (N. ceresyi and E. jesusarribasi) showed significantly lower phenoloxidase activity and antimicrobial peptide responses than their freshwater relatives (N. clarkii and E. salomonis). Encapsulation responses in freshwater species also appeared to be higher than in hypersaline relatives. Our results reinforce the complex nature of immune responses and suggest that adaptation to saline environments may have involved a trade-off between osmoregulation and investment in immune defences, but also are consistent with relaxed selection pressures on basal immune responses resulting from lower microbial infection load in saline habitats. In addition, the more resistant cuticle of species occupying such habitats may protect against the entry of parasites, reducing selection pressure on immunity. Because the evolution of salinity tolerance is associated with reduced immune capacity, saline specialists may be particularly vulnerable to the dilution of saline waters and consequent changes in pathogen communities and load following colonisation by more generalist microorganisms., This research was supported by a PhD grant from University of Murcia (FPU 2018) to MBC and a postdoctoral grant from Fundación Séneca (Agencia Regional de Ciencia y Tecnología, Región de Murcia) to SP.

Lignin is one of the main factors causing lignocellulosic biomass recalcitrance to enzymatic hydrolysis. Glasshouse-grown poplars severely downregulated for CINNAMYL ALCOHOL DEHYDROGENASE 1 (CAD1), the enzyme catalysing the last step in the monolignol-specific branch of lignin biosynthesis, have increased saccharification yields and normal growth. Here, we assess the performance of these hpCAD poplars in the field under short rotation coppice culture for two consecutive rotations of 1 yr and 3 yr. While 1-yr-old hpCAD wood had 10% less lignin, 3-yr-old hpCAD wood had wild-type lignin levels. Because of their altered cell wall composition, including elevated levels of cinnamaldehydes, both 1-yr-old and 3-yr-old hpCAD wood showed enhanced saccharification yields upon harsh alkaline pretreatments (up to +85% and +77%, respectively). In contrast with previous field trials with poplars less severely downregulated for CINNAMYL ALCOHOL DEHYDROGENASE (CAD), the hpCAD poplars displayed leaning phenotypes, early bud set, early flowering and yield penalties. Moreover, hpCAD wood had enlarged vessels, decreased wood density and reduced relative and free water contents. Our data show that the phenotypes of CAD-deficient poplars are strongly dependent on the environment and underpin the importance of field trials in translating basic research towards applications.

Stream-riparian networks are subject to multiple human pressures that threaten key functions of aquatic and terrestrial ecosystems, drive habitat and diversity losses, affect riparian connectivity and cause stakeholder conflicts. Designing riparian landscapes in a way that they can simultaneously meet multiple competing demands requires a clear understanding of existing trade-offs, and a landscape-scale perspective on the planning of reforestation measures. This study applied a landscape optimization algorithm for allocating riparian forest management measures in the intensively used agricultural catchment of the Zwalm River (Belgium). We optimized forest allocation to improve stream ecological quality (EPT index), functional diversity (diatoms) and riparian carbon processing (cotton-strip assay), while minimizing losses in agricultural production potential. Regression models were developed to predict the target indicators for 489 segments of the Zwalm riparian corridor, using spatial variables on three different scales. For each riparian segment, we developed spatially explicit management measures, representing different intensities of riparian reforestation. The allocation and combination of these measures in the riparian corridor were optimized to identify (a) trade-offs among the target indicators, (b) priority regions for reforestation actions and (c) the required reforestation intensity. The results showed that all target indicators were affected by the area share of riparian forests and its landscape-scale configuration. Reforestation of the Zwalm riparian corridor could significantly improve indicators for biodiversity and ecosystem functioning (e.g. up to +96% for EPT index), but would lead to a strong trade-off with agricultural production. By optimizing the placement of management measures, we showed how these trade-offs could be best balanced. The headwater regions of the Zwalm were identified as priority regions for reforestation actions. Facilitating connectivity among and further expansion of existing forest patches in the Zwalm headwaters showed to improve ecosystems with minimized trade-offs. Synthesis and applications. This study demonstrates, for the first time, the potential of landscape optimization algorithms to support the management and design of multifunctional stream-riparian networks. We identified riparian reforestation solutions that minimized trade-offs between specific natural values and societal needs. Our spatially explicit approach allows for an integration into spatial planning and can inform policy design and implementation.

For tidal-stream energy to become a competitive renewable energy source, clustering multiple turbines into arrays is paramount. Array optimisation is thus critical for achieving maximum power performance and reducing cost of energy. However, ascertaining an optimal array layout is a complex problem, subject to specific site hydrodynamics and multiple inter-disciplinary constraints. In this work, we present a novel optimisation approach that combines an analytical-based wake model, FLORIS, with an ocean model, Thetis. The approach is demonstrated through applications of increasing complexity. By utilising the method of analytical wake superposition, the addition or alteration of turbine position does not require re-calculation of the entire flow field, thus allowing the use of simple heuristic techniques to perform optimisation at a fraction of the computational cost of more sophisticated methods. Using a custom condition-based placement algorithm, this methodology is applied to the Pentland Firth for arrays with turbines of $$3.05\,\hbox {m}/\hbox {s}$$ 3.05 m / s rated speed, demonstrating practical implications whilst considering the temporal variability of the tide. For a 24-turbine array case, micro-siting using this technique delivered an array 15.8% more productive on average than a staggered layout, despite flow speeds regularly exceeding the rated value. Performance was evaluated through assessment of the optimised layout within the ocean model that treats turbines through a discrete turbine representation. Used iteratively, this methodology could deliver improved array configurations in a manner that accounts for local hydrodynamic effects.

There is much variation in ownership concentration among entrepreneurial firms cross-sectionally and over time. Growth potential, risk-sharing, and demand for external capital seem to be the main reasons behind the choice of low ownership concentration, and firms with diluted ownership show strong growth. After controlling for the firm fixed effects or the sample selection bias, we do not find any evidence suggesting a link between ownership concentration and other dimensions of firm performance. Therefore, the trade-off between growth aspiration and retention of dominant control of the firms may be critical in ownership structure decisions among entrepreneurial firms.

Our understanding of how novel warning color traits evolve in natural populations is largely based on studies of reproductive stages and organisms with endogenously produced pigmentation. In these systems, genetic drift is often required for novel alleles to overcome strong purifying selection stemming from frequency-dependent predation and positive assortative mating. Here, we integrate data from field surveys, predation experiments, population genomics, and phenotypic correlations to explain the origin and maintenance of geographic variation in a diet-based larval pigmentation trait in the redheaded pine sawfly (Neodiprion lecontei), a pine-feeding hymenopteran. Although our experiments confirm that N. lecontei larvae are indeed aposematic-and therefore likely to experience frequency-dependent predation-our genomic data do not support a historical demographic scenario that would have facilitated the spread of an initially deleterious allele via drift. Additionally, significantly elevated differentiation at a known color locus suggests that geographic variation in larval color is currently maintained by selection. Together, these data suggest that the novel white morph likely spread via selection. However, white body color does not enhance aposematic displays, nor is it correlated with enhanced chemical defense or immune function. Instead, the derived white-bodied morph is disproportionately abundant on a pine species with a reduced carotenoid content relative to other pine hosts, suggesting that bottom-up selection via host plants may have driven divergence among populations. Overall, our results suggest that life stage and pigment source can have a substantial impact on the evolution of novel warning signals, highlighting the need to investigate diverse aposematic taxa to develop a comprehensive understanding of color variation in nature.

[EN] The use of decision trees considerably improves the discriminating capacity of ensemble classifiers. However, this process results in the classifiers no longer being interpretable, although comprehensibility is a desired trait of decision trees. Consolidation (consolidated tree construction algorithm, CTC) was introduced to improve the discriminating capacity of decision trees, whereby a set of samples is used to build the consolidated tree without sacrificing transparency. In this work, PCTBagging is presented as a hybrid approach between bagging and a consolidated tree such that part of the comprehensibility of the consolidated tree is maintained while also improving the discriminating capacity. The consolidated tree is first developed up to a certain point and then typical bagging is performed for each sample. The part of the consolidated tree to be initially developed is configured by setting a consolidation percentage. In this work, 11 different consolidation percentages are considered for PCTBagging to effectively analyse the trade-off between comprehensibility and discriminating capacity. The results of PCTBagging are compared to those of bagging, CTC and C4.5, which serves as the base for all other algorithms. PCTBagging, with a low consolidation percentage, achieves a discriminating capacity similar to that of bagging while maintaining part of the interpretable structure of the consolidated tree. PCTBagging with a consolidation percentage of 100% offers the same comprehensibility as CTC, but achieves a significantly greater discriminating capacity. This work was funded by the Department of Education, Universities and Research of the Basque Government (ADIAN, IT980-16); and by the Ministry of Economy and Competitiveness of the Spanish Government and the European Regional Development Fund -ERDF (PhysComp, TIN2017-85409-P). We would also like to thank our former undergraduate student Ander Otsoa de Alda, who participated in the implementation of the PCTBagging algorithm for the WEKA platform.

Under controlled laboratory conditions, previous studies have shown that selection can produce repeatable evolutionary trajectories. Yet, the question remains for many of these studies if, given identical starting populations, evolution in the wild proceeds in a non-random direction. In the present study, we investigated the extent to which rapid evolution in the wild is parallel by monitoring the genetic composition of replicate populations of Daphnia in field mesocosms containing two clonal genotypes. We found parallel changes across all nine mesocosms, in which the same genotype increased in frequency. To probe whether genotype-specific response to resource abundance could have led to this frequency change, we conducted a life-history assay under high-resource abundance and low-resource abundance. We found that resource exploitation differed by genotype, in that, while one genotype (the winner in the field mesocosms) was more fit than the other genotype at high resources, the other genotype performed slightly better at low resources. We suspect that levels of resource abundance found in the summer field mesocosms had values in which the genotype better with abundant resources had the advantage. These findings suggest that variation in certain traits associated with resource acquisition can drive genotype frequency change.

Peer reviewed: True, Funder: DST-NRF Centre of Excellence at the FitzPatrick Institute, University of Cape Town, Funder: Natural Environment Research Council; Id: http://dx.doi.org/10.13039/501100000270, Funder: Pembroke College, Cambridge; Id: http://dx.doi.org/10.13039/501100004222, Parasites face a trade-off if the highest quality hosts are also most resistant to exploitation. For brood parasites, well-defended host nests may be both harder to parasitize and harder to predate, leading to better survival of parasitic chicks. This trade-off could be accentuated if brood-parasitic adaptations to reduce front-line defences of hosts, such as mimicry of hawks by Cuculus cuckoos, do not deter hosts which aggressively mob raptors. Here we investigate the costs and benefits to the African cuckoo (Cuculus gularis) of specializing on a highly aggressive host species, the fork-tailed drongo (Dicrurus adsimilis). Field experiments showed that drongos strongly attacked and mobbed both cuckoo and hawk models, implying that hawk mimicry does not deter front-line defences against African cuckoos. Attacks on cuckoo and hawk models generally declined after the egg stage but attacks on snake models sharply increased, suggesting drongos may treat hawks more like cuckoos than predators. We suggest that the cost to cuckoos of parasitizing an aggressive host may be alleviated by subsequent benefits to their offspring, since drongo nests survived better than nests of other species with similar nesting ecology. These results are indicative of a trade-off between host quality and susceptibility for a brood parasite.

La Trobe University Faculty of Science, Technology and Engineering Murray Darling Freshwater Research CentreMDFRC item.In many long-term, intensive experimental and field studies there often arises a need to trade off taxonomic resolutionfor ecological answers. Compounding this problem is a taxonomic impediment, the lack of experiencedtaxonomists capable of processing large numbers of samples to species resolution, especially in groups such as theRotifera. This paper has two aims: (1) To investigate the level of taxonomic resolution required to determine theimpact of a disturbance, in the form of a flood event; (2) to compare the impact of different taxonomic resolutionsin assessing biodiversity. Results suggest both family and generic resolution can be used to determine the impactof a flood event and that these levels have some applicability to biodiversity studies. Relatively inexperiencedtaxonomists who can identify the common rotifers to generic level, can be relied upon to detect disturbance tocommunity structure but their data become unreliable when assessing biodiversity.

Although prior research on advice solicitation has consistently shown that recipients prefer solicited advice over unsolicited advice, our study aims to tell a different story within the context of trade-off decision making. Specifically, we anticipate that recipients will respond more favorably to unsolicited advice (vs. solicited advice) when they face a trade-off between self-interest and moral self-image. In such cases, individuals desire to satisfy personal desires without experiencing moral blame, and accepting unsolicited advice that encourages them to pursue self-interest helps them achieve this goal. This is because unsolicited advice, being “uninvited”, could help them shift the responsibility of making potentially immoral decisions to others.

Plasmids are extrachromosomal segments of DNA that can transfer genes between bacterial cells. Many plasmid genes benefit bacteria but cause harm to human health by granting antibiotic resistance to pathogens. Transfer rate is a key parameter for predicting plasmid dynamics, but observed rates are highly variable, and the effects of selective forces on their evolution are unclear. We apply evolutionary analysis to plasmid conjugation models to investigate selective pressures affecting plasmid transfer rate, emphasizing host versus plasmid control, the costs of plasmid transfer, and the role of recipient cells. Our analyses show that plasmid-determined transfer rates can be predicted with three parameters (host growth rate, plasmid loss rate, and the cost of plasmid transfer on growth) under some conditions. We also show that low-frequency genetic variation in transfer rate can accumulate, facilitating rapid adaptation to changing conditions. Furthermore, reduced transfer rates due to host control have limited effects on plasmid prevalence until low enough to prevent plasmid persistence. These results provide a framework to predict plasmid transfer rate evolution in different environments and demonstrate the limited impact of host mechanisms to control the costs incurred when plasmids are present.

Are citizens willing to trade democratic institutions and practices for more authoritarian alternatives? And if yes, what is it that they prioritize and why? To answer these questions, we conduct a conjoint experiment, exposing respondents from 30 different countries -- representing both democracies and autocracies -- to a series of hypothetical country profiles, whereby we vary the attributes of these countries on the following dimensions: political institutions and civic rights, cultural-social characteristics, and economic and non-economic security. Respondents are then asked to rate the quality of life in each country. We further explore whether country characteristics of where the respondent lives and individual attributes of the respondent affect the evaluation of these hypothetical countries. This paper contributes to our understanding of regime support by taking into account the complexity of society that people face. We further provide a test of the micro mechanism of this evaluation, presenting results from a unique experiment conducted in numerous countries.

1. Differences in hatching dates can shape intraspecific interactions through size-mediated priority effects (SMPE), a phenomenon where bigger, early hatched individuals gain advantage over smaller, late hatched ones. While SMPE may be important for population dynamics, to what extent and how these are affected by key environmental factors such as warming and predation risk imposed by top predators remains unclear.2. In a laboratory experiment, we studied effects of warming (low and high temperature) and predation risk (presence and absence of predator cues of perch) on SMPE in life history and physiological traits in the cannibalistic damselfly Ischnura elegans. We induced SMPE by manipulating hatching dates, thereby creating four groups: non-mixed phenology early (E) and late (L) hatchers, and mixed phenology early (E+L) and late (L+E) hatchers. 3. We found strong SMPE for survival and emergence success, with the highest values in E+L larvae and the lowest values in L+E larvae. Neither temperature nor predator cues affected SMPE for these two life history traits. The other life history traits (development rate and mass at emergence) did not show SMPE, but were affected by temperature and predator cues.4. SMPE was found for protein content, but only in the high temperature treatment. The other physiological traits (immune function measured as phenoloxidase activity and fat content) showed fixed expressions across treatments, indicating decoupling between physiology and life history. 5. The results underline that SMPEs are trait-dependent, and only weakly affected by temperature and predation risk.

This article makes an attempt to build on the extant literature on time–cost trade-off in a transportation problem. The idea is to agglomerate the world of multiple shipment options along with the uncertainty in demand/supply requirements to the traditional set-up. The article introduces a bi-objective transportation model with multi-choice cost and time coefficients along with interval demand and supply constraints. Such a transportation framework is more generalized and provides a much broader view to a decision-maker. The research proposes an efficient iterative algorithm for generating the Pareto frontier that solves a minimum cost flow problem at each iteration. The special structure of this network flow problem is exploited to obtain computationally efficient results. The proposed method is applied to a real-world case study of UPS Express Critical in the United States. The analysis suggests that significant savings in cost and time objectives can be achieved over the traditional set-ups.

1. Repeatable individual variation in behaviour has been demonstrated in all taxa, though few studies have explored the broader ecological consequences of such consistent behaviour.2. We tagged and tracked 401 individual sea trout (Salmo trutta) with passive integrated transponder telemetry over two to four spawning seasons as they migrated between freshwater and marine environments to spawn and feed, respectively.3. We found the timing (time of river entry) and duration of migration (time spent in freshwater and time spent at sea) to be repeatable within individuals across years. In addition, we identified two peaks in return migration timing; a group of summer-migrating fish, and a group of fall-migrating fish. At the time of first spawning, sea trout differed in size depending on how long the first marine phase was, but summer-migrating fish were smaller in all subsequent spawnings. Furthermore, summer-migrating fish had significantly better marine survival than fall-migrating fish.4. Our study suggests that the timing of arrival in freshwater is an important fitness-relevant trait, such that summer-migrating fish have decreased fitness but remain in somewhat safer conditions, while fall-migrating fish have increased fitness but are exposed to more risky conditions. Taken together, our findings suggest that migration timing and duration is determined via a trade-off between size and survival, which resulted in two evolutionary stable strategies.

International audience; Multiple infections, either simultaneous or sequential, affecting a single plant or crop are now recognized to be common in plant disease epidemics. These multiple infections thus generate a range of competitive interactions (exploitation competition, apparent competition, or interference competition) that directly impact competitors' life history traits, and hence fitness. While a theoretical framework, based primarily on three ecological theories-niche exclusion, the "tragedy of the commons", and the virulence-transmission trade-off, provides insights into potential outcomes of multiple infections on pathogen evolution and virulence and on disease dynamics, experimental observations, although rather rare so far, strongly suggest that unexpected outputs can also occur. This review therefore attempts to provide a comprehensive overview of both theoretical and empirical knowledge about multiple infection in plants. It highlights the need for a detailed assessment of pathogen life history traits and their modulation according to competition types, host receptivity, and pathogen life strategies for a better understanding and prediction of the evolutionary and demographic outcomes of multiple infections, as well as research questions still open in this emerging field of plant pathology.

This paper proposes a vector error correction model to investigate the relationship between polluting emissions and GDP levels in Japan, in the period 1970-2014, and tests the validity of the Environmental Kuznets Curve (EKC) hypothesis driven by tourist arrivals. Our results validate the existence of two different causality channels among the selected variables. In particular, we find that a trade-off might exist between increasing the number of tourists, which drives economic growth, and the pattern of a sustainable development, due to the increase of polluting emissions. The analysis allows us to propose appropriate policy strategies to promote a robust and sustainable long run economic growth.

Identification of quantitative trait loci for Fusarium head blight (FHB) resistance from different sources and pyramiding them into cultivars could provide effective protection against FHB. The objective of this study was to characterize a soft red winter wheat (SRWW) breeding population that has been subjected to intense germplasm introduction and alien introgression for FHB resistance in the past. The population was evaluated under misted FHB nurseries inoculated with Fusarium graminearum-infested corn spawn for two years. Phenotypic data included disease incidence (INC), disease severity (SEV), Fusarium damaged kernels (FDK), FHB index (FHBdx), and deoxynivalenol concentration (DON). Genome-wide association studies using 13,784 SNP markers identified 25 genomic regions at -logP ≥ 4.0 that were associated with five FHB-related traits. Of these 25, the marker trait associations that explained more than 5% phenotypic variation were localized on chromosomes 1A, 2B, 3B, 5A, 7A, 7B, and 7D, and from diverse sources including adapted SRWW lines such as Truman and Bess, and unadapted common wheat lines such as Ning7840 and Fundulea 201R. Furthermore, individuals with favorable alleles at the four loci Fhb1, Qfhb.nc-2B.1 (Q2B.1), Q7D.1, and Q7D.2 showed better FDK and DON scores (but not INC, SEV, and FHBdx) compared with other allelic combinations. Our data also showed while pyramiding multiple loci provides protection against FHB disease, it has a significant trade-off with grain yield.

Eusocial insect societies possess complex multilevel disease defences, including individual level protection conferred by physical (e.g. cuticle) and immunological obstacles and colony level protection mediated by collective behaviours (social immunity). It remains unclear whether and how these two levels of disease protection are related to one another in jointly driving colonies’ susceptibility to disease. Here, we examine whether a relationship exists between individual worker survival after exposure to a fungal pathogen (a proxy for immunity) and corpse removal (a colony level social immunity metric) in the acorn ant Temnothorax curvispinosus. Since behavioural avoidance is the first line of defence against infection, we also tested whether individual ants exhibited parasite avoidance behaviour during exploration and whether colonies exhibit avoidance behaviour during foraging. We found that individual level and colony level immunity were negatively correlated: colonies that removed corpses more rapidly contained workers with weaker individual defences. We did not detect parasite avoidance behaviour by individual workers or whole colonies, nor were these two factors related. These data suggest that individual immunity and social immunity may trade off, regulating overall parasite protection. Alternatively, optimized social immunity at the colony level may compensate for disease vulnerability to infection at the individual level, and thus provide a protective benefit in overall colony defence in the absence of pathogen avoidance.

The use of translocations to recover populations requires a sufficiently large number of individuals from source populations, but removing too many individuals could lead to source population collapse. To understand the trade-off between the probabilities of source population extirpation and translocation success, matrix population models that incorporate Allee effects, density dependence, and demographic and environmental stochasticity were combined with a model that simulates removals from source populations. We apply these models to eastern sand darter (Ammocrypta pellucida; Species at Risk Act status: Threatened) translocation scenarios in Canada. The results suggest that translocations most often require source populations >20 000 individuals, as source population extirpation probability increased with the number and frequency of removals. Transport mortality or losses immediately following introduction further affected translocation success. Uncertainty around life-history parameters and the strength of Allee effects led to additional uncertainty about the required source population size. Although stochastic processes affected the probability of translocation success, factors such as stocking density and frequency can be controlled, and translocation may therefore be a viable strategy for eastern sand darter recovery, even when applying cautious thresholds to guard against uncertainty.

The proximate and ultimate mechanisms behind individual behavioural phenotypes are still only partially understood, with studies often focusing on a single or a few factor(s) that affect behaviour in a controlled environment. To understand the development and consequences of individual behavioural phenotypes in their complexity, a comprehensive approach is needed that analyses the effects of a broad spectrum of factors and their interactions on behaviour within the natural environment. We used focal observations to quantify four key behavioural components of Gala = pagos sea lion, Zalophus wollebaeki, pups under natural conditions: general social interactions, swimming, resting and social play behaviour. We then investigated the influence and interplay of age, sex, body condition, basal cortisol and testosterone levels, personality scores and the social environment on the observed behaviour. We identified significant correlations between all measured factors and behaviour. Complex interactions between testosterone, boldness and social play especially stand out, with the effect of boldness on social play being dependent on testosterone levels. We also demonstrate the importance of the early social environment, defined as local population density, for social play and, interestingly, time spent swimming. This could have consequences for the development of social and hunting skills, crucial for later stages of ontogeny. For this endangered pinniped, a decline in the diversity of social environments due to dwindling population numbers could lead to a decline in behavioural diversity and lower coping abilities towards future changes in their environment. Our study reveals important factors for the development of individual behavioural phenotypes of young Gala = pagos sea lions and elucidates some aspects of the architecture behind this individual variation in behaviour. (c) 2021 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

With increasing depths of mining, difficult reef geologies, reduced overall mine productivity, as well as the increasing cost lines associated with mining in the narrow tabular property; the current blasting related mining methods prove to be less efficient. This is owing to low efficiency, higher effect on the surrounding rock, possible fly rock, dilution, personnel in danger line and production of toxic gases, etc. These challenges have resulted in a 13.5% (101.3 tonnes) and 2.9% (262.9 tonnes) decrease in gold and platinum production, 14% and 2.6% increase in gold and platinum costs and the rate of change in safety has started to flatten out. Several recent studies emphasize the development and utilization of non-explosive techniques of mechanical rock cutting that are integrated into continuous mining systems, and one of these techniques is reef boring. The work is aimed at determing the most suitable mining method between blasting technique methods (conventional B and P, conventional breast, mechanised B and P, and mechanised breast) and rock cutting technique method (reef boring which involves the drilling of narrow tabular reef and extracting the chippings for processing). The most suitable method is determined through a trade-off study. The trade-off study (mining method evaluation) was conducted through the use of simulations based on BME (Basic Mining Equations) and BFE (Basic Financial Equations) calculations, Risk assessments, Trade-off analysis: weighing, scoring, and comparisons of the mining method. The inputs of the study were derived from the literature survey that was conducted on different mining methods. The background information gathered on these mining methods focussed on ore extraction, material handling, support, labour, equipment, and benefits & challenges of each mining method. Using that background information together with mine benchmarking, a mock mine was created with the following orebody characteristics: thickness of 1.1 m, dipping at 15°, and an average grade of 4.12 g/t at a depth of 1.1 km. This ore deposit was extracted using all five mining methods investigated. The mining parameters for each mining method were based on the literature study information and first principles. The trade-off analysis was based on the selection criteria that includes production, cost, safety, dilution percentage, extraction percentage, flexibility, and automation. Based on the results, reef boring method produces the highest tonnages of 10 651 oz/month, has the highest profit of R303 million/month, highest NPV of R1 423 million, highest IRR of 88%, and highest ROCE of 296%. Due to these factors, the reef boring is the most profitable mining method compared to drilling and blasting methods. Also, it has the least dilution percentage of 2% and the highest extraction percentage of 98%. The reef boring method has the least number of employees on the face (10 people), fewer hazards are associated with the equipment and the reef boring machine causes the least disturbance on the surrounding rock. Hence, it is the safest method with maximised automation. However, even though the reef boring method is more feasible in the paper, practically for high performance the machine should be able to drill 18 h per hole and extract 1000 m and above.

In every construction project, the time and cost are the two most important objectives/factors to be considered. Clients and contractors should strive to optimize the project time and cost to maximize the return. Resources are also one of the major constraints of the construction projects. In recent years, several studies have been conducted to optimize the time and cost of project under constraint conditions of resources. Since most studies assume the time and cost as deterministic parameters, uncertainties should be considered in estimating the time and cost of the project's activities when minimizing the duration and cost of the project. For this purpose, this paper embeds the fuzzy logic to handle the uncertainties in estimating the time and cost. Besides, the multi-objective genetic algorithm (MOGA) is used to develop the resourceconstrained time-cost trade-off model. Alpha-cut approach is utilized to define the accepted risk level of decision maker. The efficiency of the proposed model is demonstrated through solvinga case study project of highway construction. The results of case study project provide a set of Pareto-optimal solutions. The developed model encourage the decision making process by choosing specified risk levels and utilizing the related Pareto-front. Keywords: Construction projects, time-cost trade-off, uncertainties, fuzzy logic, MOGA,Pareto-optimal solution.

A traditional agroforestry of West Timor, namely Mamar, produces important ecosystem services to the people of this arid region, however, its management tends to change, thereby disrupting its sustainability. This study aims to assess the sustainability of Mamar agroforestry by analyzing the livelihood assests of the community, the biophysical land performance of the soil, and the value of ecosystem services. Furthermore, data, on perception and livelihood assets; the level of soil damage, the importance value index, and diversity index, the value of ecosystem services based on the opinion of experts and community leaders, as well as change in land use were collected in five villages in Kupang district using surveys with a qualitative and quantitative approach. The results showed a change of perspective in Mamar's management; the decrease in the important value index of cultural crops, the diversity index is classified as declining, there is soil damage in several parameters, and the value of ecosystem services does not focus on cultural services. Considering this result, there is a socio-ecological trade-off that reduces support for the sustainability of Mamar as traditional agroforestry that emphasizes socio-cultural functions.

Pandemics attack the primary asset (labor) of peasant households and the rural poor. Peasant households must simultaneously allocate labor between farm and household activities, where the demand for agricultural labor is seasonal, which limits intra-temporal substitution, without perfect foresight. A pandemic reduces the supply of labor, through deaths and morbidity, with the scale of reductions in labor supply depending on the seasons in which a pandemic occurs. The analyses, using a recursive dynamic economy-wide model for Bhutan, demonstrate that outbreaks in high labor demand seasons cause increases in wage rates almost three times as high as for outbreaks in low labor demand seasons. Increases in wage rates induce peasant households to reallocate labor time between farm and household activities through the labor-leisure trade-off mechanism. Such changes in the allocation of labor time are important elements of peasants’ mitigation responses, and can reduce the negative economic implications of a pandemic. © 2021 The International Input--Output Association.

It has been suggested that a trade-off between hydraulic efficiency and safety is related to drought adaptation across species. However, whether leaf hydraulic efficiency is sacrificed for safety during woody resprout regrowth after crown removal is not well understood. We measured leaf water potential (ψleaf ) at predawn (ψpd ) and midday (ψmid ), leaf maximum hydraulic conductance (Kleaf-max ), ψleaf at induction 50% loss of Kleaf-max (Kleaf P50 ), leaf area-specific whole-plant hydraulic conductance (LSC), leaf vein structure and turgor loss point (πtlp ) in 1- to 13-year-old resprouts of the aridland shrub (Caragana korshinskii). ψpd was similar, ψmid and Kleaf P50 became more negative, and Kleaf-max decreased in resprouts with the increasing age; thus, leaf hydraulic efficiency clearly traded off against safety. The difference between ψmid and Kleaf P50 , leaf hydraulic safety margin, increased gradually with increasing resprout age. More negative ψmid and Kleaf P50 were closely related to decreasing LSC and more negative πtlp , respectively, and the decreasing Kleaf-max arose from the lower minor vein density and the narrower midrib xylem vessels. Our results showed that a clear trade-off between leaf hydraulic efficiency and safety helps C. korshinskii resprouts adapt to increasing water stress as they approach final size.

This paper synthesizes concepts from the design creativity and design optimization literatures to develop a conceptual descriptive model of trade-off situations in design. Using a set theory approach, a model of the design space is expanded to formalize the description of trade-offs as Pareto frontiers on this space. The modelling of design process and human biases and limitations on the structure of these design spaces explores the perceptions designers form of these design spaces. The model presented describes how altering the framing and formulation of the design space can be used to alter or bypass the original Pareto frontiers of that space, allowing trade-offs to be navigated outside of the original limitations.

How and if organisms can adapt to changing temperatures has drastic consequences for the natural world. Thermal adaptation involves finding a match between temperatures permitting growth and the expected temperature distribution of the environment. However, if and how this match is achieved, and how tightly linked species change together, is poorly understood. Paramecium bursaria is a ciliate that has a tight physiological interaction with endosymbiotic green algae (zoochlorellae). We subjected a wild population of P. bursaria to a cold and warm climate (20 and 32℃) for ∼300 generations. We then measured the thermal performance curve (TPC) for intrinsic rate of growth (rmax ) for these evolved lines across temperatures. We also evaluated number and size of the zoochlorellae populations within paramecia cells. TPCs for warm-adapted populations were shallower and broader than TPCs of cold-adapted populations, indicating that the warm populations adapted by moving along a thermal generalist/specialist trade off rather than right-shifting the TPC. Zoochlorellae populations within cold-adapted paramecia had fewer and larger zoochlorellae than hot-adapted paramecia, indicating phenotypic shifts in the endosymbiont accompany thermal adaptation in the host. Our results provide new and novel insight into how species involved in complex interactions will be affected by continuing increasing global temperatures.

Maternal effects are ubiquitous. Yet, the pathways through which maternal effects occur in wild mammals remain largely unknown. We hypothesise that maternal immune transfer is a key mechanism by which mothers can affect their offspring fitness, and that individual variation in maternally-derived antibodies mainly depends on a mother’s characteristics and the environmental conditions she experiences. To test this, we assayed six colostrum-derived anti bodies in the plasma of 1,447 neonates in a wild red deer population. Neonatal antibody levels were mainly affected by maternal genes, environmental variation, and costs of prior reproductive investment. We found consistent heterogeneity in maternal performance across traits, with mothers producing the heaviest calves also having calves with more antibodies. Unexpectedly, antibody levels were not associated with calf survival. We provide a unique example of how evolutionary theory on maternal effects can be used to gain insight into the causes of maternal effects in wild populations.

This paper investigates the trade-off between economics and ethics applying them to “lockdowns” as a policy measure to counter the Covid-19-pandemic. This is an academic research on the nature and mechanism of trade-offs in so far as they apply to decision making. In the course of the line of inquiry pursued here, several different ways of trading off are assessed. In applying them to the pandemics, each yield a different answer to the adequacy of lockdowns as measures against the pandemic. The economic trade-off found “optimalcy” conditions, the utilitarian-ethical trade-off failed to do so revealing that there is a problem using “scientific evidence” as basis for such a trade-off. The value-ethical trade-off found out that lockdowns do not pass the test of proportionality within the usual constitutional framework.

In this study, we investigated which strategy Macrobrachium amazonicum populations use to survive in river and estuary environments. In each environment, abiotic factors were analyzed in situ, and ovigerous females and males of M. amazonicum specimens were captured. To determine ovarian maturity and morphotypes, gonads were removed and processed histologically, and the gonadosomatic index and condition factor (K) were determined. Ovigerous females were analyzed to determine the relationship between ovarian maturation and the embryonic phases of eggs in the brood pouch. Precipitation, turbidity and dissolved oxygen showed differences between the estuary and river. The population of ovigerous females showed that ovarian maturation was simultaneous with embryonic development. However, the freshwater prawn populations in the river were smaller and consisted of a greater number of ovigerous females with maturing and mature ovaries. In the estuary, ovigerous females with spawned and reorganized ovaries were observed more frequently. In males, the GC morphotype was absent in the river, where the TC morphotype predominated and showed similar reproductive conditions as the GC morphotype in the estuary. M. amazonicum has strategies for allocating energy for reproduction or growth in different environments. This description established the trade-off as a strategy used by M. amazonicum to maintain the population in adverse environments.

The coronavirus disease 2019 (COVID-19) pandemic has exerted tremendous effects on the residents of and caregivers at long-term care facilities (LTCF). The combination of a vulnerable, aged population, staffing shortages, and inadequate resources in LTCF will cause a great negative impact in these sectors. Addressing the caregiver’s lack of interest in providing care for patients with COVID-19 is a great challenge for institutional managers. The primary objective of this study was to analyze the factors related to the willingness of personnel at LTCF to provide care to patients with COVID-19. This was a cross-sectional study in which personnel from 10 LTCF were recruited as participants through convenience sampling and completed structured questionnaires. A total of 500 questionnaires were distributed and 385 valid questionnaires were recovered, posting a response rate of 77%. A statistical analysis was performed using SPSS 22.0. The results of the survey revealed that only 30% of the participants were willing to provide care to patients with COVID-19; 23% more of the participants were willing to provide such care if their institutions provided sufficient PPE. Regarding other conditions, 31.5% and 76% of the participants expressed that they would be willing to provide such care if their compensation were increased and working hours were reduced. In the univariate analysis, the willingness of participants with different characteristics (job categories, years of holding a professional certificate, job location type, monthly income, experience with caring for patients with confirmed COVID-19, and completion of training related to communicable disease control) varied significantly (p < 0.05). Furthermore, in the logistic regression analysis, several demographic and professional characteristics (education level, job category, number of patients served daily, and monthly income) were significantly correlated with willingness to provide care to patients with COVID-19 (p < 0.05). On the basis of these findings, the LTCF should securitize the associated factors of care wiliness in personnel to eliminate the difference of the willingness to provide care to patients with suspected or confirmed COVID-19.

This page contains data and resources associated with "Trade-off drives Pareto optimality of within- and among-year emergence timing in response to increasing aridity" by Joseph Waterton, Susan J. Mazer, Justin R. Meyer and Elsa E. Cleland.

AI technology is increasingly establishing itself as a prominent decision-maker in our daily lives. An important topic for discussion concerns the maintenance of human autonomy. Do we mind giving up our everyday agency (i.e., the capacity of individuals to act independently and to make their own free choices) to intelligent machines? Does it matter if we surrender agency to AI as opposed to a human? And do we accept automated decisions more readily if the benefits are great enough, even if they mean giving up agency? In this study, we use everyday life decision scenarios in a 2(participant agency: yes/no) X 2(benefits high/low) vignette experiment, in which participants must make an explicit choice between a human or AI decision-maker, based on how they trade-off their own agency and the decision’s benefits potential.

To reduce strategic misreporting on sensitive topics, survey researchers increasingly use list experiments rather than direct questions. However, the complexity of list experiments may increase nonstrategic misreporting. We provide the first empirical assessment of this trade-off between strategic and nonstrategic misreporting. We field list experiments on election turnout in two different countries, collecting measures of respondents’ true turnout. We detail and apply a partition validation method which uses true scores to distinguish true and false positives and negatives for list experiments, thus allowing detection of nonstrategic reporting errors. For both list experiments, partition validation reveals nonstrategic misreporting that is: undetected by standard diagnostics or validation; greater than assumed in extant simulation studies; and severe enough that direct turnout questions subject to strategic misreporting exhibit lower overall reporting error. We discuss how our results can inform the choice between list experiment and direct question for other topics and survey contexts.

Growth and reproduction are two essential life‐history traits for fungi. Understanding life‐history strategies provides insight into the environmental adaption of species. Here, we investigated the colonial morphology, vegetative growth, and asexual reproduction of the ascomycete fungus Bionectria ochroleuca in response to a variety of environmental conditions. We demonstrated that the increased temperature from 15 to 25°C induced mycelial growth and conidiation in B. ochroleuca. We also found that the optimal temperatures for mycelial growth and conidial formation in this fungus species were 25 and 30°C, respectively. However, as the temperature increased from 25 to 30°C, mycelial growth was suppressed, but the total number of conidia was significantly increased. The shift in light–dark cycles dramatically changed the morphological features of the colonies and affected both vegetative growth and asexual reproduction. Under incubation environments of alternating light and dark (16:8 and 8:16 light:dark cycles), conidiophores and conidia in the colonies formed dense‐sparse rings and displayed synchronous wave structures. When the light duration was prolonged in the sequence of 0, 8, 16, and 24 hr per day, mycelial growth was suppressed, but conidiation was promoted. Together, our results indicate that temperature and light period may trigger a trade‐off between vegetative growth and asexual reproduction in B. ochroleuca.

Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Río Negro, Argentina. Fil: Sáez, Agustín. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medio Ambiente Argentina. Río Negro, Argentina. Fil: Gleiser, Gabriela. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medio Ambiente Argentina. Río Negro, Argentina. Fil: Strelin, Marina M. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medio Ambiente Argentina. Río Negro, Argentina. Domestication generally involves two sequential processes: initial identification of wild species with desirable characteristics (‘progenitor filtering’) and subsequent artificial and natural selection that, respectively, improve features preferred by humans and adapt species to cultivation/captivity (‘domestication selection’). Consequently, domesticated species can differ from wild species and may share characteristics owing to convergent evolution (‘domestication syndrome’). Baring evolutionary constraints, domestication selection may generate extreme phenotypes that transcend the ‘boundaries of nature’ evident for wild species. Despite evidence of domestication syndromes in some clades, broader contributions of progenitor filtering and domestication selection to characteristics of contemporary domesticated species have received limited attention. Using comparative analysis of 49 grain-crop and 87 wild annual plant species from 15 families, we (1) addressed whether plants of crop and wild species differ for mean seed number, per-seed mass and total seed-mass investment; (2) assessed contributions of (a) progenitor filtering and (b) domestication selection to these differences; (3) evaluated whether crop characteristics exceed the boundaries of nature and (4) assessed whether seed-production characteristics of grain crops constitute components of a generic domestication syndrome. On average, grain-crop plants produce heavier seeds and greater total seed mass than wild species, but seed number per plant does not differ. Comparison of wild species between genera with or without crop species found no evidence of progenitor filtering. In contrast, crop species differed from congeneric wild species for the mass traits, but not for seed number. Greater seed investment by crops is consistent with artificial selection for enhanced seed yield (mass per harvested area), whereas heavier individual seeds suggest selection for improved nutritional quality and (or) adaptation to cultivation environments. Seed number–size characteristics of grain-crop species lie within the bivariate variation among wild species and so do not exceed the boundaries of nature. Seed number and size varied similarly between species types and generally aligned with seed-investment isoclines, suggesting an upper investment limit. Despite greater average investment in seed production and individual seeds by grain-crop species, seed-production characteristics did not vary less among crop species than among wild species, which is inconsistent with a common domestication syndrome. Domestication generally involves two sequential processes: initial identification of wild species with desirable characteristics (‘progenitor filtering’) and subsequent artificial and natural selection that, respectively, improve features preferred by humans and adapt species to cultivation/captivity (‘domestication selection’). Consequently, domesticated species can differ from wild species and may share characteristics owing to convergent evolution (‘domestication syndrome’). Baring evolutionary constraints, domestication selection may generate extreme phenotypes that transcend the ‘boundaries of nature’ evident for wild species. Despite evidence of domestication syndromes in some clades, broader contributions of progenitor filtering and domestication selection to characteristics of contemporary domesticated species have received limited attention. Using comparative analysis of 49 grain-crop and 87 wild annual plant species from 15 families, we (1) addressed whether plants of crop and wild species differ for mean seed number, per-seed mass and total seed-mass investment; (2) assessed contributions of (a) progenitor filtering and (b) domestication selection to these differences; (3) evaluated whether crop characteristics exceed the boundaries of nature and (4) assessed whether seed-production characteristics of grain crops constitute components of a generic domestication syndrome. On average, grain-crop plants produce heavier seeds and greater total seed mass than wild species, but seed number per plant does not differ. Comparison of wild species between genera with or without crop species found no evidence of progenitor filtering. In contrast, crop species differed from congeneric wild species for the mass traits, but not for seed number. Greater seed investment by crops is consistent with artificial selection for enhanced seed yield (mass per harvested area), whereas heavier individual seeds suggest selection for improved nutritional quality and (or) adaptation to cultivation environments. Seed number–size characteristics of grain-crop species lie within the bivariate variation among wild species and so do not exceed the boundaries of nature. Seed number and size varied similarly between species types and generally aligned with seed-investment isoclines, suggesting an upper investment limit. Despite greater average investment in seed production and individual seeds by grain-crop species, seed-production characteristics did not vary less among crop species than among wild species, which is inconsistent with a common domestication syndrome.