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Society as a whole faces a host of economic tradeoffs, many of which emerge around economic policies. An example of tradeoffs that any society faces in many economic realms is the tradeoff between economic efficiency and income equality (aka the efficiency-equality tradeoff). This tradeoff has been called "the Big Tradeoff" by the esteemed economist Arthur Okun, who also termed it "the Double Standard of a Capitalist Democracy." Although the efficiency-equality tradeoff is more or less an inevitable tradeoff in most societal settings and economic contexts, there are still some special circumstances in which this tradeoff can be avoided. This paper identifies five such avenues and elaborates on why and how the tradeoff between these two somewhat contradictory societal goals—efficiency and equality—can be deftly averted under the mentioned circumstances. These avenues with their transformative potential can and should be used so that a capitalist society as an integrated whole can promote both efficiency and equality at the same time under these scenarios and avoid facing the Big Tradeoff in cases where it is evitable. Static and dynamic economic models are developed, solved, and applied to facilitate the articulation and exposition of the main points of each solution with formal rigor and logical coherence. Finally, policy implications are discussed. [ABSTRACT FROM AUTHOR]

Predator–prey interactions drive the evolution of prey visual camouflage, but prey species also must remain conspicuous to their conspecifics for social signaling purposes. Whether rapid body color change can help to balance conspecific visibility and predator concealment, in the eyes of each group's respective visual systems, remains poorly understood. We tested this question using water anoles (Anolis aquaticus), a small lizard that uses rapid dark-to-light body color change to visually camouflage itself from its avian predators across diverse microhabitats. We used digital image analysis and visual modeling to assess the effectiveness of color-matching camouflage in dark- and light-phase A. aquaticus, as perceived by anoles and avian predators. Our findings reveal that A. aquaticus body coloration was perceived similarly by both groups. However, sex-specific differences in overall conspicuousness emerged, with males more consistently color matching their microhabitats compared to females. Females were less likely to color match their backgrounds in their lighter phase, suggesting a sex difference in preferred conspicuity in more exposed habitats. We highlight the context-dependence of color change, with sex-specific differences and microhabitat potentially affecting its function. Significance statement: Predator and prey visual systems influence prey species' visual camouflage evolution, but whether rapid body color changes allow animals to dynamically balance conspecific visibility with predator concealment is not well known. We used visual modeling techniques to examine if water anoles (Anolis aquaticus), small lizards that employ rapid body color changes to evade their avian predators, appear differently to their predators and conspecifics depending on color phase. Our findings reveal that A. aquaticus body coloration is perceived similarly by both groups. However, we observed sex-specific differences: males and larger individuals displayed more consistent color matching across different microhabitats, whereas females showed reduced matching in their lighter phase. Our study underscores the context-dependence of the function of color change in relation to factors including sex and microhabitat. [ABSTRACT FROM AUTHOR]

In network services, there are often conflicts among privacy protection, trust, and service quality, which greatly reduces the regulatory effectiveness of networks. Using the basic method of information theory, this paper considers the optimization mechanism of trust and the balance between privacy and service utility from the perspective of quantifying information flow. First, we build a trust model based on multiple factors, such as direct trust, service trust, and trust cloud network. The weight of trust factors is determined by category diversity and information entropy theory. Second, based on statistical knowledge and information entropy, we propose a new privacy measurement model with hierarchical weights. Third, we establish a trust privacy service relationship model to realize the trade-off between privacy, service, and trust in networks. The demander can choose to establish trust, protect privacy, or obtain high-quality services according to personal preferences and needs. Fourth, we propose a privacy trust mapping relationship model and a privacy disclosure selection model. Finally, we design different experimental schemes. These simulation results show that our research can not only provide better quality of service but also better protect privacy and help interactive parties in networks establish a strong trust relationship. This research will improve the effectiveness of networks and can be applied to class II vaccine multi-agent collaborative supervision based on technology. [ABSTRACT FROM AUTHOR]

Males and females often differ in use of antipredator behaviors, particularly when antipredator behavior comes at the cost of missed mating opportunities or territory defense. When using thermally suboptimal refugia, ectotherms are especially vulnerable to these costs, as their performance is linked to body temperature. To flee from predators, semi-aquatic Anolis lizards dive underwater for long periods and rebreathe from a bubble of air. We hypothesized that using aquatic refugia would result in body heat loss, that dive duration is influenced by sex, and that oxygen consumption when diving would help explain sex differences. We tested these hypotheses by measuring dive length and body temperatures in A. aquaticus, and by recording oxygen consumption and final oxygen partial pressure during controlled dives in several semi-aquatic Anolis species. Not only was there a significant thermal cost to diving, but A. aquaticus males and females appeared to tolerate different levels of this cost: males re-emerged from water more quickly and at higher body temperatures than did females. Body temperature decreased according to an exponential decay function, dropping up to 6 °C in 5 min. Oxygen consumption rates in semi-aquatic anoles were primarily explained by the expected allometric scaling relationship with mass and, therefore, are unlikely to lead to sex differences in physiological limits to dive times. Instead, shorter male dives may help them maintain physiological performance, mating opportunities or territory defense. Antipredator diving behavior is physiologically costly but undoubtedly beneficial to both sexes, highlighting the need for further study of sex-based antipredator optimization. Significance statement: To avoid predators, semi-aquatic Anolis lizards can dive underwater and remain there for an extended time by rebreathing a bubble of air over their heads. In this study, we reveal that diving to escape predators also comes with a cost: submersion in water reduces lizard body temperatures. Reduced body temperature can impair a lizard’s ability to move quickly and defend mates or territories, suggesting that there may be divergent diving behaviors in males and females. Our findings confirm that males do indeed spend less time underwater than females. We measured oxygen consumption during dives, and our data suggest that sex differences in diving behavior are unrelated to oxygen use. This study sheds light on the sex-specific balance of antipredator behaviors and the maintenance of optimal body temperatures, and more broadly contributes insight into adaptive responses to environmental challenges. [ABSTRACT FROM AUTHOR]

A Benefit Risk Assessment Plan (BRAP) describes the assessments planned to determine whether the benefits of an investigational drug outweigh the risks. The plan can have two sections, one with timelines for aligning resources with decision milestones and the other for pre-specifying assessments for decision milestones. Regulatory guidance recommends a proactive planning process over an ad-hoc process. However, very little has been published about proactive plans themselves. This article works through a hypothetical example visualizing a series of assessments across the drug development lifecycle. Based on a regulatory framework, the planning process starts with assessing the medical condition and current treatment options. These early assessments bring out major considerations in assessing the investigational drug. [ABSTRACT FROM AUTHOR]

Abstract Plasmid fitness is directed by two orthogonal processes—vertical transfer through cell division and horizontal transfer through conjugation. When considered individually, improvements in either mode of transfer can promote how well a plasmid spreads and persists. Together, however, the metabolic cost of conjugation could create a tradeoff that constrains plasmid evolution. Here, we present evidence for the presence, consequences, and molecular basis of a conjugation‐growth tradeoff across 40 plasmids derived from clinical Escherichia coli pathogens. We discover that most plasmids operate below a conjugation efficiency threshold for major growth effects, indicating strong natural selection for vertical transfer. Below this threshold, E. coli demonstrates a remarkable growth tolerance to over four orders of magnitude change in conjugation efficiency. This tolerance fades as nutrients become scarce and horizontal transfer attracts a greater share of host resources. Our results provide insight into evolutionary constraints directing plasmid fitness and strategies to combat the spread of antibiotic resistance.

Urban agglomeration will be the main mode of future urbanization in China, greatly influencing social and economic development and ecosystem protection at the whole city cluster scale. It is important to analyze the impacts of large-scale, scattered land use and cover change (LUCC) consisting of one-pole-multi-point urbanization in city clusters on regional ecosystem services (ESs), so as to increase ecological security and maintain ES levels. Using the urban–rural gradient analysis method (UGAM), this study examined driver-response mechanisms of large-scale, scattered agglomeration urbanization on ESs along an urban–rural gradient and at a regional scale. This was done by simulating and analyzing tempo-spatial variations in ES characteristics along concentric ring gradients in the Central Yunnan City Cluster (CYCC) under its present urbanization path. The results showed that rapid urban sprawl is the main driver affecting the integral value of ESs in CYCC and that ES trade-offs (through LUCC caused by urbanization) between adjacent zones along the urban–rural gradient will particularly exacerbate the degradation of integral ES levels. Hence, CYCC should follow a sustainable, eco-friendly urbanization path and consider ecological principles and the impact of LUCC on regional ESs along the urban–rural gradient in top-level design and decision-making on urban planning and strategic land use management. Differentiated regional development policies should be formulated for each area, the urban–rural development pattern and layout optimized, the scale of construction land rationally controlled, and the overall efficiency of land use improved. Ecological buffers should be set up around areas with sharp and obvious changes in land use, to alleviate the negative impact of large-scale, decentralized city cluster urbanization on regional ESs. [ABSTRACT FROM AUTHOR]

Nowadays, users are becoming more reserved in uploading their own data to the servers of service providers for fear of personal information disclosure. In order to meet the need on privacy security, Federated Learning (FL) is proposed. As the nearest servers to users, edge servers are quite suitable for the execution of FL tasks, which results in a new concept called Federated Edge Learning (FEEL). It allows users to conduct model training locally without uploading their own data, thus avoiding privacy disclosure. However, the issue of Energy Consumption (EC) for training on devices becomes a main concern for users because the learning process is carried out on the devices with limited battery capacity. Then, from the standpoint of service providers, they pay more attention to the model performance (i.e., test dataset accuracy of the trained machine learning model) and usually have diverse requirements on it. Both EC and model performance are important metrics for FEEL, and from our engineering experience, service providers and users may have a conflict of interest in FEEL. In this paper, after modeling the two metrics, we identify the common factor (i.e., size of the training data) between them and are convinced that there is a tradeoff. Then, we add a workload constraint that regulates the common factor to the formulated problem and propose a resource optimization and device scheduling strategy to solve it, thus achieving the tradeoff between EC and model performance of FEEL. This strategy is based on the steepest descent method and approximation algorithm. The approximation ratio is also proved. By regulating the training workload threshold, the values of the two metrics can be dynamically adjusted. Achieving the tradeoff makes it possible to meet the needs of service providers and users at the same time. More specifically, it can minimize the energy consumption of training devices on the premise of meeting diverse requirements of service providers on model performance, which can not be realized by other FEEL frameworks that do not achieve the tradeoff. Simulation results show that our proposed strategy is able to achieve this tradeoff compared with two existing FEEL frameworks. Compared with another existing FEEL framework who also realizes the tradeoff, the tradeoff achieved by our proposed strategy is more biased towards EC. At the end of the simulation part, we summary the characteristics of the proposed and other three existing FEEL frameworks. [ABSTRACT FROM AUTHOR]

Hypoxia is a seasonally recurring environmental condition in small temperate lakes during summer thermal stratification and under ice cover in winter. Anthropogenic eutrophication contributes significantly to hypoxia by increasing primary production of organic materials that subsequently decompose in the hypolimnion. Greenhouse gas emissions that increase global temperatures will reduce the capacity of water to hold dissolved gases such as oxygen and increase the duration of thermal stratification and thus increase the severity and duration of hypoxic conditions in temperate lakes. How hypoxia may impact assessment of predation risk is under-studied. Here, we present a test of the effect of low dissolved oxygen (~ 1 ppm) on antipredator behavioral responses to conspecific alarm cues by fathead minnows. When alarm cues derived from conspecific epidermal tissues were introduced, fish under normoxic conditions (~ 9 ppm) reduced activity and moved out of the water column to spend more time at the bottom. These behaviors serve to reduce the probability of predation. At low dissolved oxygen levels, fathead minnows engaged in aquatic surface respiration, i.e., "drinking" the surface film of oxygen-rich water. When alarm cues were introduced, minnows left the surface waters to dash briefly downward but soon returned to the surface and did not reduce their activity. Taken together, these data indicate that under oxygen stress, minnows engage in truncated antipredator responses and remain near the surface where they would be more vulnerable to avian predators or air-breathing invertebrates such as belastomatids. Through decreased availability of dissolved oxygen, global climate change is likely to disrupt predator–prey interactions in temperate lakes. [ABSTRACT FROM AUTHOR]

Blockchain Technology (BCT) is expanding day by day and is used in all pillars of life and projects. In this research, we survey applicable BCT in project management for the first time. We presented a Resource-Constrained Time–Cost-Quality-Energy-Environment Tradeoff Problem by considering BCT, Risk and Robustness (RCTCQEETPBCTRR) in project scheduling. We utilize hybrid robust stochastic programming, worst case, and Conditional Value at Risk (CVaR) to cope with uncertainty and risks. This type of robustification and risk-averse is presented in this research. A real case study is presented in a healthcare project. We utilize GAMS-CPLEX to solve the model. Finally, we analyze finish time, conservative coefficient, the confidence level of CVaR, and the number of scenarios. The most important research result is that applying BCT decreases cost, energy, and pollution and increases quality. Moreover, the total gap between RCTCQEETPBCTRR and without BCT is approximately 2.6%. When compacting finish time happens or if the conservative coefficient increases to 100%, costs, energy, and pollution environment increase, but quality decreases. If the confidence level of CVaR increases, the cost, energy, and environment function functions grow up, and quality is approximately not changed. [ABSTRACT FROM AUTHOR]

Values are important factors shaping people's perceptions of social–ecological changes and the associated impacts, acceptable risk, and successful adaptation to various changes; however, little empirical work has examined how values interact to influence adaptation decision-making. We drew on 25 semi-structured interviews with community leaders, farmers, fisherfolk, and individuals in the tourism industry in northwestern Pakistan to identify types of adaptations employed by households and explore what values were present in these households' adaptation decisions. Our results show that households frequently employed environmental management and livelihood diversification to adapt to a wide range of social–ecological change. We found that multiple values influenced household adaptation and that employing an adaptation strategy often involved a tradeoff of values. We also found that household adaptations were embedded in multi-scalar social, cultural, economic, and political processes that could constrain or conflict with such adaptations. Overall, our research illustrates the complex influence of values on household adaptation decisions and highlights the need to further understand how adaptations are aligned, or misaligned, with stakeholders' diverse values in order to inform more equitable adaptation to social–ecological change. [ABSTRACT FROM AUTHOR]

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]

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]

We develop data structures for intersection queries in four dimensions that involve segments, triangles and tetrahedra. Specifically, we study three main problems: (i) Preprocess a set of n tetrahedra in R4\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathbb {R}^4$$\end{document} into a data structure for answering segment-intersection queries amid the given tetrahedra (referred to as segment-tetrahedron intersection queries). (ii) Preprocess a set of n triangles in R4\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathbb {R}^4$$\end{document} into a data structure that supports triangle-intersection queries amid the input triangles (referred to as triangle-triangle intersection queries). (iii) Preprocess a set of n segments in R4\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathbb {R}^4$$\end{document} into a data structure that supports tetrahedron-intersection queries amid the input segments (referred to as tetrahedron-segment intersection queries). In each problem we want either to detect an intersection, or to count or report all intersections. As far as we can tell, these problems have not been previously studied. For problem (i), we first present a “standard” solution which, for any prespecified value n≤s≤n6\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$n \le s \le n^6$$\end{document} of a so-called storage parameter s, yields a data structure with O∗(s)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$O^*(s)$$\end{document} storage and expected preprocessing, which answers an intersection query in O∗(n/s1/6)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$O^*(n/s^{1/6})$$\end{document} time (here and in what follows, the O∗(·)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$O^*(\cdot )$$\end{document} notation hides subpolynomial factors). For problems (ii) and (iii), using similar arguments, we present a solution that has the same asymptotic performance bounds. We then improve the solution for problem (i), and present a more intricate data structure that uses O∗(n2)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$O^*(n^{2})$$\end{document} storage and expected preprocessing, and answers a segment-tetrahedron intersection query in O∗(n1/2)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$O^*(n^{1/2})$$\end{document} time, improving the O∗(n2/3)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$O^*(n^{2/3})$$\end{document} query time obtained by the standard solution. Using the parametric search technique of Agarwal and Matoušek (SIAM J Comput 22:794–806, 1993), we can obtain data structures with similar performance bounds for the ray-shooting problem amid tetrahedra in R4\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathbb {R}^4$$\end{document}. Unfortunately, so far we do not know how to obtain a similar improvement for problems (ii) and (iii). Our algorithms are based on a primal-dual technique for range searching with semi-algebraic sets, based on recent advances in this area (Agarwal et al. in SIAM J Comput 50:760–787, 2021. Also in Proceedings of Symposium on Computational Geometry (SoCG) 5:1–5:14, 2019. Also in arXiv:1812.10269; Matoušek and Patáková in Discrete Comput Geom 54:22–41, 2015). As this is a result of independent interest, we spell out the details of this technique. We present several applications of our techniques, including continuous collision detection amid moving tetrahedra in 3-space, an output-sensitive algorithm for constructing the arrangement of n tetrahedra in R4\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathbb {R}^4$$\end{document}, and an output-sensitive algorithm for constructing the intersection or union of two or several nonconvex polyhedra in R4\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathbb {R}^4$$\end{document}. [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]

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]

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]

The problem of a priori estimation of the result of a mulicriteria two-person competitive game is considered in the framework of operations research. Various aspects of decision making in such games are discussed. Relations between the values of a vector best guaranteed result (BGR) for both players are obtained. The difference of the mulicriteria antagonistic game considered as a model of taking into account the natural uncertainty from the mulicriteria zero-sum game considered as interaction with a purposeful opponent is formalized. Special attention is paid to the concepts of the value and solution of the latter game. As the basic solution of this game, we use the multicriteria Shapley equilibrium when it gives to each player the result not worse than her or his BGR. It is shown that the last condition is not restrictive. The definition of the one-sided value of the multicriteria game as the player's BGR if her BGR is independent of the order of the players' moves and the definition of the corresponding one-sided solution are given. It is proved that the equilibrium is weaker than the one-sided solution, and the equilibrium always exists in mixed strategies. The existence of a one-sided solution in mixed strategies is guaranteed by a special interpretation of multicriteria averaging. To justify the conclusions, Slater's value of the multicriteria optimum is parameterized using Germeier's scalarizing function. [ABSTRACT FROM AUTHOR]

Inter-individual variation in lifetime reproduction is the key target for natural selection, and it is influenced by many factors. Yet, we lack an understanding of how abiotic and biotic factors interact to influence lifetime reproductive output (number of offspring) and reproductive effort (total biomass invested into reproduction). Thus, we used a factorial design to manipulate variability in food availability and temperature while also accounting for mate quality. We tested hypotheses related to estimates of lifetime reproductive output and effort in females of the wing-dimorphic sand field cricket (Gryllus firmus). Environmental variability influenced a temporal tradeoff of reproduction because females experiencing fluctuating temperatures had a particular bias toward reproductive output during early adulthood. Also, complex environmental variability (i.e., multiple and co-varying environmental factors) influenced differential allocation, which is when individuals adjust their reproductive efforts according to mate quality. Females mated to higher quality males laid more eggs only in environments that were highly stable (constant temperature and ad libitum food access). Reproductive effort was affected by a food–temperature interaction—fluctuating temperatures promoted egg production when food was limited, while constant temperature promoted egg production when food was abundant. Although a wing dimorphism mediates a well-established flight–fecundity tradeoff during early adulthood in G. firmus, short- and long-winged morphs exhibited similar lifetime reproduction and responded similarly to complex environmental variability. Given the natural co-variation of many environmental factors (e.g., water limitation often accompanies heat waves), we encourage continued work examining the role of complex environmental variability in tradeoffs related to reproductive decision-making and allocation. Significance statement: It is unclear how abiotic and biotic factors interact to influence lifetime reproductive output (number of offspring) and reproductive effort (total biomass invested into reproduction). Thus, we examined the effects of mate quality and complex environmental variability (variable food and temperature) on several metrics of lifetime reproduction. Female crickets mated to high-quality males had greater reproductive output, but only in highly stable or environmental conditions. Fluctuating temperatures biased reproductive output toward early adulthood, particularly in short-winged females. Reproductive effort was affected by a food–temperature interaction—fluctuating temperatures promoted egg production when food was limited, while constant temperature promoted egg production when food was abundant. Females can also retain unfertilized eggs, and egg retention (i.e., unrealized fitness potential) was influenced by a combination of mate quality and complex environments. Thus, it is important to carefully consider the interplay between biotic and abiotic factors in aspects of lifetime reproduction and reproductive decision-making. [ABSTRACT FROM AUTHOR]

Invasive woody plants from Europe and Asia tend to be more productive than co-occurring native species in deciduous forests of Eastern North America, but community-scale drivers of invasion success remain unknown. If increased productivity in invaders relative to natives comes at the expense of reduced relative allocation to defenses, generalist herbivores may preferentially consume invasive species, potentially reducing the effectiveness of invader growth advantage. We compared leaf traits related to herbivory (nitrogen concentration, total phenolics, cellulose and lignin concentrations, and leaf dry matter content) in 20 phylogenetically paired native and non-native, invasive species and evaluated species palatability to two generalist herbivores: one non-native (European gypsy moth, Lymantria dispar) and one native (fall webworm, Hyphantria cunia). We also evaluated potential physiological tradeoffs between defense-related leaf traits, leaf production, and carbon storage in this group of species. Invasive plants had higher leaf N and lignin concentrations than related native species (0.5% and 5%, respectively), but gypsy moth and fall webworm growth were not associated with plant nativity. Plant defense traits did not predict differences in gypsy moth growth, but fall webworm growth was marginally negatively associated with leaf N. We found no evidence of tradeoffs between defense-related leaf traits, leaf production, and carbon storage, indicating a limited role for carbon-based tradeoffs relating to growth and herbivory in these species, although other unmeasured carbon pools including reproduction may impact these relationships. Woody invaders continue to spread in Eastern North American forest understories, but we found no evidence of inhibition or facilitation by generalist insect herbivores, despite differences among species in leaf traits associated with defense. [ABSTRACT FROM AUTHOR]

Animals travelling through the environment often face trade-offs between environmental parameters such as risk, travel speed and ease of movement when selecting their routes. Route selection is of particular importance for central place foragers like ants, which collectively and repeatedly use trails to exploit stable sources of food. We investigated how colonies of meat ants (Iridomyrmex purpureus) select and clear trail routes when faced with semi-permeable obstructions (strips of grass turf) that substantially slow their travel speed. Meat ant colonies usually re-routed their trails to avoid obstructions when short strips of turf were laid across existing trails, but always travelled directly across the turf when avoiding the turf would have significantly increased travel time. No significant difference in trail clearing activity was found between the short and long obstruction treatments. On binary mazes, meat ants were equally likely to choose paths obstructed with turf and equal length smooth paths, despite much higher time costs associated with the obstructed route. Colonies always chose the shorter, turf-covered path on mazes where the length of the smooth path was increased by 50%, suggesting that meat ants prioritise the minimisation of travel distance when selecting new trail routes. Meat ant route selection and clearing behaviour may reflect a long-term foraging optimisation strategy whereby colonies pay high short-term costs to minimise long-term travelling costs by selecting relatively direct, short distance trail routes which can be cleared of obstructions over time. [ABSTRACT FROM AUTHOR]

Abstract Stress response genes and their regulators form networks that underlie drug resistance. These networks often have an inherent tradeoff: their expression is costly in the absence of stress, but beneficial in stress. They can quickly emerge in the genomes of infectious microbes and cancer cells, protecting them from treatment. Yet, the evolution of stress resistance networks is not well understood. Here, we use a two‐component synthetic gene circuit integrated into the budding yeast genome to model experimentally the adaptation of a stress response module and its host genome in three different scenarios. In agreement with computational predictions, we find that: (i) intra‐module mutations target and eliminate the module if it confers only cost without any benefit to the cell; (ii) intra‐ and extra‐module mutations jointly activate the module if it is potentially beneficial and confers no cost; and (iii) a few specific mutations repeatedly fine‐tune the module's noisy response if it has excessive costs and/or insufficient benefits. Overall, these findings reveal how the timing and mechanisms of stress response network evolution depend on the environment.

Seasonal environments favor the evolution of capital breeding, whereby reproduction uses surplus energy from resources acquired during an earlier period. Consequently, reproductive effort in capital breeders is expected to depend on traits associated with energy storage rather than environmental conditions at the time of reproduction. Based on a 15-year dataset, we investigate the effect of phenotype (body size and condition) and environmental conditions (intensity of hydrological seasons, predator density, and density of conspecifics) on fecundity three capital breeding fish species from the strongly seasonal Amazon River floodplain: Psectrogaster rutiloides, Triportheus angulatus, and Acestrorhynchus falcirostris. Fecundity of all three species was strongly correlated with phenotype and modulated by unfavorable environmental conditions during the period of reproduction, especially high density of conspecifics. Fecundity was negatively affected by the density of conspecifics for small females of A. falcirostris, and for T. angulatus females with poor body condition. Fecundity of P. rutiloides declined during periods of drought when density of conspecifics was highest. A clear tradeoff between quantity and quality of oocytes was found only for P. rutiloides. This study highlights that reproductive allocation of capital breeders in seasonal environments is strongly linked to environmental conditions before and during the reproductive period. [ABSTRACT FROM AUTHOR]

Recently the energy efficiency (EE) in wireless communication is becoming one of the key performance metric for wireless communicating systems. For battery driven system like wireless sensor networks and ad-hoc networks, the energy conservation is a critical factor for node life. In addition, the spectral efficiency (SE) has been traditionally used as a performance index for wireless transmission. This paper investigates the optimum spectral to energy efficiency tradeoff especially for short range communications. The analysis starts with the Shannon case in additive white gaussian noise channel where some theoretic results are developed when considering both transmit and circuit energy. Then, point to point communication system with uncoded M-ary quadrature amplitude modulation (MQAM) is considered. At the device layer, a system level power consumption model is proposed. At the physical layer, a novel and accurate approximation of the bit error rate (BER) function of the signal to noise ratio is made. The total energy per bit is formulated and the link between the Shannon limit capacity and MQAM based communication is established. The impact of distance, bandwidth, power consumption and BER as a quality-of-service parameter on EE-SE tradeoff is analyzed. It is shown that, varying distance, bandwidth and circuit power consumption induce more impact in the low SE regime whereas, the BER has more impact on the high SE regime. Moreover, the energy optimal spectral efficiency for MQAM is obtained in closed-form and confirmed by numerical results. [ABSTRACT FROM AUTHOR]

The aims of this study were (1) to prepare cinnarizine (CNZ)-β-cyclodextrin (β-CD) complexes by the kneading, co-precipitation and co-evaporation methods with (ternary system) or without (binary system) the addition of two different hydrophilic polymers [hydroxypropyl methylcellulose (HPMC) and polyvinylpyrrolidone (PVP)] in their two different grades (HPMC E5-LV or K4M and PVP K-25 or K-30) and (2) to determine the polymers influence on enhancing the CNZ solubility and the in vitro CNZ liberation behaviour or drug permeation characteristics via artificial membrane from the prepared CNZ-β-CD binary and ternary complexes in 0.1 N HCl (pH 1.2). The presence of hydrophilic polymers in ternary complex system did produce irregular-shaped but smooth-surfaced particles while binary complex system (with no polymer addition) did not. The ternary complexes prepared with HPMC K4M, β-CD and CNZ showed higher solubility efficiency value compared to other tested hydrophilic polymers to make ternary complex systems. Consequently, irrespective of the three preparation methods, the ternary complex systems exhibited higher drug libration behaviour in comparison to the binary complex system, physical mixtures and CNZ powder. But because of the possible presence of a solubility and permeability interplay or tradeoff particularly in the binary and ternary complex systems, the CNZ permeation amount in 0.1 N HCl (pH 1.2) via artificial membrane was established to a minimum compared to the CNZ powder. Therefore, the CNZ-β-CD complexes with or without the HPMC and PVP should unequivocally be used with great care by considering the solubility-permeability interplay or tradeoff into account. [ABSTRACT FROM AUTHOR]

In this paper, we provide a comprehensive literature survey on simultaneous wireless information and power transfer (SWIPT) in multi-antenna systems. We first review recent contributions on the theory analysis of SWIPT from information theoretic standpoint and introduce the tradeoff between information transfer and power transfer under various settings. Then, we focus on the utilization of multi-antenna techniques to solve existing problems of SWIPT. Contributions on the implementation aspects of multi-antenna SWIPT are summarized. The performance of SWIPT is evaluated by different metrics, therefore, we review the works on dynamic SWIPT optimization based on objective function using multi-antenna techniques. In addition, the implementation of SWIPT brings up secure issue. Thus, we summarize recent works on secure SWIPT. Finally, we present researches combining SWIPT with state-of-the-art techniques due to potential application in different scenarios. [ABSTRACT FROM AUTHOR]

This study explores the tradeoff relationship between the number of initial attack firefighting resources and the level of fire ignition prevention efforts mitigating the probability of human-made fires in the Republic of Korea, where most fires are caused by human activities. To examine this tradeoff relationship, we develop a hybrid model that combines a robust optimization model with a stochastic simulation model. The robust optimization minimizes the expected number of fires not receiving a pre-defined response, such as the number of firefighting resources that must arrive at the fire within half an hour, subject to budget constraints and uncertainty about the daily number and location of fires. The simulation model produces a set of fire scenarios in which a combination of number, location, ignition time, and intensity of fires occur. Results show that fire ignition prevention is as cost-effective as initial attack firefighting resources given the current budget in the Republic of Korea for reducing the expected number of fires not covered by the predefined response. The mixed policy of fire suppression and fire prevention may produce some gains in efficiency relative to the dominant policy of strong fire suppression strategies. [ABSTRACT FROM AUTHOR]

This paper contributes to the process of eliciting additive model scale constants in order to support choice problems, thereby reducing the effort a decision maker (DM) needs to make since partial information with regard to DM preferences can be used. Procedures related to eliciting weights without a tradeoff interpretation of weights are justified based on assumptions that DM is not able to specify fixed weight values or if DM is able to do so, this would not be reliable information. As long as partial information is provided, the flexible elicitation procedure performs dominance tests based on a linear programming problem to explore the DM's preferences as a vector space which is built using the DM's partial information. To provide evidence of the satisfactory performance of the flexible elicitation procedure, an empirical test is presented with results that indicate that this procedure requires less effort from DMs. [ABSTRACT FROM AUTHOR]

Practical and optimal reduction of watershed loads under deep uncertainty requires sufficient search alternatives and direct evaluation of robustness. These requirements contribute to the understanding of the tradeoff between cost and robustness; while they are not well addressed in previous studies. This study thereby (a) uses preconditioning technique in Evolutionary Algorithm to reduce unnecessary search space, which enables a sufficient search; and (b) derives Robustness Index (RI) as a second-tier optimization objective function to achieve refined solutions (solved by GA) that address both robustness and optimality. Uncertainty-based Refined Risk Explicit Linear Interval Programming is used to generate alternatives (solved by Controlled elitist NSGA-II). The robustness calculation error is also quantified. Proposed approach is applied to Lake Dianchi, China. Results demonstrate obvious improvement in robustness after conducting sufficient search and negative robustness-optimality trade-offs, and provides a detailed characteristic of robustness that can serve as references for decision-making. [ABSTRACT FROM AUTHOR]

Providing fair bandwidth allocation for applications is becoming increasingly compelling in cloud datacenters, as different applications compete for the shared datacenter network resources. While existing solutions mainly provide bandwidth guarantees for virtual machines (VMs) or tenants with the aim of achieving the VM-level or tenant-level fairness of bandwidth allocation, scant attention has been paid to providing bandwidth guarantees for applications to achieve the fairness of application performance (utility). In this paper, we introduce a rigorous definition of application-level utility max-min fairness, which guides us to develop a non-linear model to investigate the relationship between the utility fairness and bandwidth allocation for applications. Based on such a model, we further arbitrate the intrinsic tradeoff between the network bandwidth utilization and utility fairness of application bandwidth allocation, using a tunable fairness relaxation factor. To improve the bandwidth utilization while maintaining the strict utility fairness of bandwidth allocation, we design UFalloc, an application-level Utility max-min Fair bandwidth allocation strategy in datacenter networks. With extensive experiments using OpenFlow in Mininet virtual network environment, we demonstrate that UFalloc can achieve high utilization of network bandwidth while maintaining the utility max-min fair share of bandwidth allocation with a certain degree of fairness relaxation, yet with an acceptable computational overhead. [ABSTRACT FROM AUTHOR]

Topology Control is one of the most important techniques used in wireless multi-hop networks to obtain the desired network property. The most conventional MST-based topology control schemes both achieve a very good performance in terms of transmission power and implicitly consider network capacity, but they hardly have flexibility in determining whether more importance is placed on network capacity or not. Therefore, we jointly consider network capacity and energy efficiency in this paper. A new localized topology control scheme is proposed to meet the above two competing objectives by finding a balance between them through using Get_min- cost_for_link_(). The simulation results show that, when compared with some typical MST-based schemes, the proposed scheme can achieve the desired performance in terms of network capacity under the appropriate combination of weight values though it has a slightly worse performance in terms of transmission power. Moreover, the proposed scheme achieves the most balanced distribution with respect to path capacity among the compared schemes, especially when both k-hop neighborhood size and network node density increase. More importantly, the proposed scheme can flexibly determine that either network capacity or energy consumption should be given more attention according to the demand of the network application. [ABSTRACT FROM AUTHOR]

Purpose: Some medical treatment for metastatic colorectal cancer (CRC) may have marginal survival benefit, but cause toxicities. The purpose of this study is to determine metastatic CRC patients' tradeoffs in making a decision to undergo new medical treatment. Methods: We conducted a survey of patients with a diagnosis of advanced CRC who were currently receiving or completed one chemotherapy regimen. First, patients were asked to rate the importance of 15 medical treatment-related adverse events that may arise as a consequence of chemotherapy or biological therapy in their treatment decision-making. Then, the patient identified his or her top five most important events and solicited preferences in hypothetical metastatic CRC treatment vignettes using the standard gamble technique. Results: A total of 107 patients responded to the survey. From the list of medical treatment-related adverse events, patients identified clinically serious ones such as stroke, heart attack, and gastrointestinal perforation as the most important in their medical treatment decision-making, yet placed lower willingness to tolerate symptom-related events such as pain, fatigue, and depression. Generally, patients who were older, stage III versus IV and who had prior radiotherapy, lower educational attainment, and lower household income (all p <0.05) were less willing to tolerate any medical treatment-related adverse events after adjusting for other demographic and clinical characteristics. Conclusions: Variations in patients' willingness to tolerate different treatment-related adverse events underscore the need for improved communications between physicians and patients about the risks and benefits of their medical treatment, which helps make a more personalized decision for metastatic CRC treatment. [ABSTRACT FROM AUTHOR]

To examine the tradeoff between manual reaction times (RTs) and smooth pursuit accuracy, we manipulated manual RTs to a visual target presented during pursuit by using a deadline procedure that required different response speeds to a target (300, 400, or 500 ms). Participants attempted to pursue a moving row of circles as accurately as possible, while responding to a target within a preset time. Stimulus velocity and target position were manipulated. As the preset time became shorter, participants responded with faster manual RTs and larger pursuit velocity errors, irrespective of the stimulus velocity, indicating a tradeoff between manual RTs and pursuit accuracy. Pursuit velocity errors were also larger after target onset. These results not only suggest that attentional resources as well as spatial shifts of attention play an important role in maintaining accurate pursuit, but also support the notion that a manual RT task is useful for revealing the operation of attention during pursuit. [ABSTRACT FROM AUTHOR]

The time-optimal control for boost converters can achieve the minimum recovery time. However, their output voltage deviation is quite large. Since the minimum output voltage deviation and minimum recovery time cannot be obtained at the same time, a novel energy control is proposed to achieve a superior tradeoff between them in this paper. The peak value of the inductor current can be decreased as well. Its control parameter is easy to choose. When compared with the conventional control methods, the proposed control shows a better dynamic performance. Experimental results, which are in agreement with the theoretical analysis, are provided to verify the proposed control method. [ABSTRACT FROM AUTHOR]

Both plant competition and plant defense affect biodiversity and food web dynamics and are central themes in ecology research. The evolutionary pressures determining plant allocation toward defense or competition are not well understood. According to the growth-differentiation balance hypothesis (GDB), the relative importance of herbivory and competition have led to the evolution of plant allocation patterns, with herbivore pressure leading to increased differentiated tissues (defensive traits), and competition pressure leading to resource investment towards cellular division and elongation (growth-related traits). Here, we tested the GDB hypothesis by assessing the competitive response of lima bean ( Phaseolus lunatus) plants with quantitatively different levels of cyanogenesis-a constitutive direct, nitrogen-based defense against herbivores. We used high (HC) and low cyanogenic (LC) genotypes in different competition treatments (intra-genotypic, inter-genotypic, interspecific), and in the presence or absence of insect herbivores (Mexican bean beetle, Epilachna varivestis) to quantify vegetative and generative plant parameters (above and belowground biomass as well as seed production). Highly defended HC-plants had significantly lower aboveground biomass and seed production than LC-plants when grown in the absence of herbivores implying significant intrinsic costs of plant cyanogenesis. However, the reduced performance of HC- compared to LC-plants was mitigated in the presence of herbivores. The two plant genotypes exhibited fundamentally different responses to various stresses (competition, herbivory). Our study supports the GDB hypothesis by demonstrating that competition and herbivory affect different plant genotypes differentially and contributes to understanding the causes of variation in defense within a single plant species. [ABSTRACT FROM AUTHOR]

This study presents a multiobjective optimization algorithm that is termed memetic algorithm with compromise search (MACS). This algorithm, proposed by the authors, combines genetic evolution with local search, in the same way as traditional memetic algorithms, but with the use of independent populations for each objective, as well as a mechanism for finding compromise solutions (tradeoffs) via a local search operator. The algorithm was applied to a parallel machine scheduling problem involving a molding production process in the wood industry. The algorithm was compared against four multiobjective techniques available in the literature: the multiobjective genetic algorithm (MOGA), the strength Pareto evolutionary algorithm (SPEA), the non-sorting genetic algorithm II (NSGA II), and multiobjective genetic local search (MOGLS). The proposed approach outperformed the benchmark techniques in most of the test problems based on two objectives of industrial interest: minimization of the maximum completion time (Cmax) and minimization of total tardiness. These objectives are directly related to the productivity of the product and the ability to deliver goods on time. [ABSTRACT FROM AUTHOR]

Costs of mating effort can affect the reproductive strategies and lifetime fitness of male primates, but interspecific and interindividual variation in the magnitude and distribution of costs is poorly understood. Male costs have primarily been recognized in seasonally breeding species that experience concentrated periods of mating competition. Here, we examine foraging costs associated with male mating effort in chimpanzees ( Pan troglodytes schweinfurthii), a polygynandrous species, in which mating opportunities occur intermittently throughout the year. To quantify male feeding, aggression, and mating, we conducted focal follows on 12 males in a wild community (Kanyawara, Kibale National Park, Uganda) for 11 mo. Males fed less on days when high-value mating opportunities (estrous parous females) were available than on days without any mating opportunities. Reductions in feeding time were related to increased rates of aggression and copulation, indicating that the proximate cause of changes in male foraging was mating effort. Surprisingly, however, there was no relationship between dominance rank and the extent to which feeding time was reduced. High costs of mating effort may reduce the degree of reproductive skew and limit the use of possessive tactics in chimpanzees. We suggest that male bonding in chimpanzees may be favored not only for its benefits but because intragroup competition is so costly. Our results complement the available data on mammals, and primates in particular, by showing that mating effort can have measurable foraging costs even in species, in which breeding is aseasonal and only moderately skewed. [ABSTRACT FROM AUTHOR]

Morphological variation is often attributed to differential adaptations to diverse habitats, but adaptations to a similar environment do not necessarily result in similar phenotypes. Adaptations for water and heat budget are crucial for organisms living in arid habitats, and in snails, variation in shell morphology has been frequently attributed to selection by stressful environmental factors. However, their phenotypic divergence often is not accompanied by a relevant niche differentiation and consistent relationships with environmental correlates are lacking. In the pulmonate genus Albinaria, there is great size and shape variation between and within species, and there are two major shell sculpture morphotypes, ribbed and smooth. We used 62 populations of 28 Albinaria species, taking into account their phylogeny, to examine the variation of shell traits (sculpture, size, shape), their effect on water and heat budget, and their association with geographical and climatic gradients. We found unambiguous size and shape discrimination between the two morphotypes. Ribbed shells are lighter, taller, and slimmer and have a smaller aperture than the smooth ones. Moreover, significant correlations between shell traits and heat/moisture budget and climate/geography were revealed. Ribbed and taller shells retain more water on their shell surface, and on the other hand, smooth shells exhibit lower water permeability. Therefore, two strategies are being used to prevent water loss, active retention or resistance to loss. Consequently, different alternative solutions evolved and were retained as responses to the same stressful factor by the two distinct shell morphotypes. Larger shells occur in southern latitudes, mostly on islands, and at sites where there is a shortage of rainfall. Therefore, the variation of the examined traits is nonrandom with respect to location and to climate and their evolution can be attributed to selection by environmental factors, with water availability being the key driving agent of body-size variation. [ABSTRACT FROM AUTHOR]

Today, mobile platforms are multimedia devices that provide different types of traffic with the consequent particular performance demands and, besides, security concerns (e.g. privacy). However, Security and QoS requirements quite often conflict to a large degree; the mobility and heterogeneous paradigm of the Future Internet makes coexistence even more difficult, posing new challenges to overcome. Probably, one of the main challenges is to identify the specific reasons why Security and QoS mechanisms are so related to each other. In this paper, we present a Parametric Relationship Model (PRM) to identify the Security and QoS dependencies, and to elaborate on the Security and QoS tradeoff. In particular, we perform an analysis that focus on the mobile platform environment and, consequently, also considers subjective parameters such user's experience, that is crucial for increasing the usability of new solutions in the Future Internet. The final aim of our contribution is to facilitate the development of secure and efficient services for mobile platforms. [ABSTRACT FROM AUTHOR]

Layered Steered Space-Time Codes (LSSTC) is a recently proposed multiple-input multiple-output (MIMO) system that combines the benefits of vertical Bell Labs space-time (VBLAST) scheme, space-time block codes (STBC) and beamforming. In this paper, we derive the error performance and capacity of a single-user LSSTC system. The analysis is general enough to any layer ordering and modulation schemes used. In addition, the derived analysis is general for any LSSTC structure in which layers may have different number of antenna arrays and may be assigned power according to any power allocation. Furthermore, we analytically investigate the tradeoff between the main parameters of the LSSTC system, i.e., diversity, multiplexing and beamforming. Our results give recursive expressions for the probability of error for LSSTC which showed nearly perfect match to the simulation results. Results have also revealed the possibility of designing an adaptive system in which it was shown that combining beamforming, STBC, and VBLAST has better performance than VBLAST at high SNR range. [ABSTRACT FROM AUTHOR]

In this paper, a novel semi-orthogonal distributed Alamouti space-time codes transmission protocol is proposed for a four nodes cooperative communication system consisting of one source, one destination and two semi blind relays over block fading channels. In particular, by semi-orthogonal we mean two orthogonal frequency bands are invoked, one of which is for the transmission by the source node, while the other one is shared simultaneously by the two relay-destination links. Moreover, analytical performances of the proposed semi-orthogonal scheme are investigated in this paper. Specifically, the theoretical expressions of the exact SER and diversity order are presented. Our proposed scheme is capable of achieving higher spectral efficiency and remaining the same diversity order compared to the existing orthogonal one, while attaining better symbol error rate performance and higher diversity order against the non-orthogonal design. Finally, simulation results prove the correctness of the above conclusions and also verify our derivation for the analytical performances. [ABSTRACT FROM AUTHOR]

Plants usually express multiple chemical and mechanical defenses simultaneously. The interplay of these defenses is still poorly understood, as predictions range from negative associations such as allocation tradeoffs to positive correlations forming synergistic defense syndromes. Surprisingly, little empirical evidence exists on the co-variation of multiple plant defenses. In the present study, we analyzed different genotypes of lima bean ( Phaseolus lunatus L.) for the expression of two direct chemical defenses [cyanogenic potential (constitutive), polyphenol oxidase activity (inducible)], two indirect chemical defenses [volatiles (VOCs) and extrafloral nectar (EFN; both inducible)] and a constitutive mechanical defense (hook-shaped trichomes). While the occurrence of trichomes was positively correlated with cyanogenesis, these traits showed a tradeoff with polyphenol oxidase activity, release of VOCs, and secretion of EFN. Hook-shaped trichomes were abundantly present in four of 14 genotypes investigated, and were found only in one monophyletic group of an AFLP-based tree, thus indicating a single evolutionary origin within the species. Our findings show that different lima bean genotypes express either one of two defense systems: 1) high constitutive defense via cyanogenesis and trichomes or 2) high inducible defense via VOCs, EFN, and PPO activity. [ABSTRACT FROM AUTHOR]

Energy efficiency has been an important concern in wireless sensor networks where Medium Access Control (MAC) protocol plays an important role. However, current MAC protocols designed for energy saving have seldom considered multiple applications coexisting in WSN with variation of traffic load dynamics. In this paper, we propose an adaptive control algorithm at MAC layer to promote energy efficiency. We focus on the tradeoff relation between collisions and control overhead as a reflection of traffic load and propose to balance the tradeoff under the constraints of QoS options. We integrate the algorithm into S-MAC and verify it through NS-2 platform. The simulation results demonstrate that our algorithm achieves observable improvement in energy performance while meeting QoS requirement for different coexisting applications in comparison with S-MAC. [ABSTRACT FROM AUTHOR]

The response of ecological communities to environmental disturbances depends not just on the number of species they contain but also on the functional diversity of the constituent species; greater variation in the tolerance of species to different environmental disturbances is generally thought to confer greater resistance to the community. Here, I investigate how the functional diversity of communities changes with environmental disturbances. Specifically, I assume that there is variation in traits among species that confer tolerance or sensitivity to environmental disturbances. When a disturbance occurs, variation in species tolerances causes changes in the relative abundances of species, which in turn changes the average tolerance of the community. For example, if tolerance to an environmental disturbance is conferred by large body size, then the environmental disturbance should be expected to increase the average body size of individuals in the community. Despite this expectation, ecological interactions among species can affect the average community response. For example, if larger species are also strong competitors with each other, then this might reduce the increase in average body size in the community, because interspecific competition limits the grow in population density of large bodied species. Similarly, when disturbances affect multiple traits, the covariance in the distribution of trait values among species may restrict the response of any one trait; if two traits provide tolerance to the same disturbance but negatively covary among species, then the response of one trait will limit the response of the other trait at the community level. Using a Lotka-Volterra model for competitive communities, I derive general formulae that generate explicit predictions about the changes in average trait values in a community subject to environmental disturbances. These formulae demonstrate that competition can impede the change in average community trait values. However, the impediment is not considerable in comparison to the predominant factors of trait variances and species selection effects when species with the most similar trait values also experience the greatest interspecific competition. Similarly, negative covariances among different traits that confer resistance to the same environmental disturbance will impede their responses. I illustrate these results using phytoplankton data from a whole-lake experiment in which manipulation to the zooplankton community created a disturbance to the phytoplankton that changed the selective consumption of large vs. small phytoplankton. [ABSTRACT FROM AUTHOR]

In Cognitive Radio (CR) networks, CR user has to detect the spectrum channel periodically to make sure that the channel is idle during data transmission frame in order to avoid the collisions to the primary users. Hence recent research has been focused on the interference avoidance problem. Quality of Service (QoS) requirement of CR user will affect the time of data transmission in each frame. In this paper, in order to solve the interference avoidance and spectrum utilization problems without cooperation among CR users, a new scheme to obtain the optimal duration of data transmission frame is proposed to maximize the spectrum utilization and guarantee the protection to the primary users. The main advantages of our proposed scheme include the followings: (1) QoS requirement of CR user is concerned; (2) p-persistent Media Access Control (MAC) random access is used to avoid the collisions among CR users; (3) CR network system capacity is considered. We develop a Markov chain of the primary spectrum channel states and an exponential distribution of the CR user's traffic model to analyze the performance of our proposed scheme. Computer simulation shows that there is an optimal data transmission time to maximize the spectrum utilization. However, the regulatory constraint of the collision rate to the primary users has to be satisfied at the expense of spectrum utilization. And also the tradeoff between the spectrum utilization and the capacity of the CR system is taken into account. [ABSTRACT FROM AUTHOR]