Planning Benefit-Risk Assessments Using Visualizations

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.

Changes in selection of resources with reproductive state in a montane ungulate

Animals select habitats based on food, water, space, and cover. Each of those components are essential to the ability of an individual to survive and reproduce in a particular habitat. Selection of resources is linked to reproductive fitness and individuals likely vary in how they select resources relative to their reproductive state: during pregnancy, while provisioning young when nutritional needs of the mother are high, but offspring are vulnerable to predation, or if they lose young to mortality. We investigated the effects of reproductive state on selection of resources by maternal female desert bighorn sheep (Ovis canadensis nelsoni) by comparing selection during the last trimester of gestation, following parturition when females were provisioning dependent young, and if the female lost an offspring. We captured, and recaptured each year, 32 female bighorn sheep at Lone Mountain, Nevada, during 2016-2018. Captured females were fit with GPS collars and those that were pregnant received vaginal implant transmitters. We used a Bayesian approach to estimate differences in selection between females provisioning and not provisioning offspring, as well as the length of time it took for females with offspring to return levels of selection similar to that observed prior to parturition. Females that were not provisioning offspring selected areas with higher risk of predation, but greater nutritional resources than those that were provisioning dependent young. When females were provisioning young immediately following parturition, females selected areas that were safe from predators, but had lower nutritional resources. Females displayed varying rates of return to selection strategies associated with access to nutritional resources as young grew and became more agile and less dependent on mothers. We observed clear and substantial shifts in selection of resources associated with reproductive state, and females exhibited tradeoffs in favor of areas that were safer from predators when provisioning dependent young despite loss of nutritional resources to support lactation. As young grew and became less vulnerable to predators, females returned to levels of selection that provided access to nutritional resources to restore somatic reserves lost during lactation.

Modern zoning plans versus traditional landscape structures: Ecosystem service dynamics and interactions in rapidly urbanizing cultural landscapes

Cultural landscapes provide abundant and diverse ecosystem services (ES) for human-wellbeing. However, many traditional cultural landscapes worldwide are currently undergoing rapid urbanization. In decision-making concerning sustainable urbanization, tradeoffs frequently occur between different objectives (i.e., between multiple ES) and between different pathways or urbanization strategies (e.g., following modern zoning principles or traditional landscape structures). This study aims to examine the dynamics and interactions between multiple ES under different strategies for the urbanization of cultural landscapes. A case study was conducted in Nansha, China. Three scenarios-business-as-usual, zoning plan-based, and traditional landscape structure-based-were developed to reflect the most common urbanization strategies, each parameterized with identical land-use quantities. Land-use change from 2020 to 2035 under different scenarios was simulated using the PLUS model (integrated Random Forest and Cellular Automata models). The traditional landscape structure-based scenario used the settlement pattern before urbanization to predict the chances of future urban areas' occurrence. Eleven ES indicators were used to examine ES dynamics and interactions in the simulation outcomes. The results showed that the amount of ES provided by the landscape declined and significant tradeoffs occurred between cultural and non-cultural ES. The business-as-usual scenario resulted in the greatest decrease in ES. The zoning plan-based scenario did not offer a significant improvement over the business-as-usual scenario. The traditional landscape structure-based scenario was the most effective in limiting ES decline, which also mitigated the tradeoff between urban development and flood regulation and fostered synergy between urban efficiency and ecotourism opportunity. Based on these findings, we recommend that traditional landscape structures should be emphasized in the development of cultural landscapes.

Impacts of urbanization at city cluster scale on ecosystem services along an urban-rural gradient: a case study of Central Yunnan City Cluster, China

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.

Plant invasions facilitated by suppression of root nutrient acquisition rather than by disruption of mycorrhizal association in the native plant

Invasive species have profound negative impacts on native ranges. Unraveling the mechanisms employed by invasive plant species is crucial to controlling invasions. One important approach that invasive plants use to outcompete native plants is to disrupt mutualistic interactions between native roots and mycorrhizal fungi. However, it remains unclear how differences in the competitive ability of invasive plants affect native plant associations with mycorrhizae. Here, we examined how a native plant, Xanthium strumarium, responds to invasive plants that differed in competitive abilities (i.e., as represented by aboveground plant biomass) by measuring changes in root nitrogen concentration (root nutrient acquisition) and mycorrhizal colonization rate. We found that both root nitrogen concentration and mycorrhizal colonization rate in the native plant were reduced by invasive plants. The change in mycorrhizal colonization rate of the native plant was negatively correlated with both aboveground plant biomass of the invasive plants and the change in aboveground plant biomass of the native plant in monocultures relative to mixed plantings. In contrast, the change in root nitrogen concentration of the native plant was positively correlated with aboveground plant biomass of the invasive plants and the change in aboveground plant biomass of the native plant. When we compared the changes in mycorrhizal colonization rate and root nitrogen concentration in the native plant grown in monocultures with those of native plants grown with invasive plants, we observed a significant tradeoff. Our study shows that invasive plants can suppress native plants by reducing root nutrient acquisition rather than by disrupting symbiotic mycorrhizal associations, a novel finding likely attributable to a low dependence of the native plant on mycorrhizal fungi.

Resource-constrained time-cost-quality-energy-environment tradeoff problem by considering blockchain technology, risk and robustness: a case study of healthcare project

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.

Adaptation to Social-Ecological Change in Northwestern Pakistan: Household Strategies and Decision-making Processes

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.

Suitable chemical fertilizer reduction mitigates the water footprint of maize production: evidence from Northeast China

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.

The salt secretion of leaves promotes the competitiveness of Reaumuria soongarica in a desert grassland

BACKGROUND

For better understanding the mechanism of Reaumuria soongarica community formation in a salt stressed grassland ecosystem, we designed a field experiment to test how leaves salt secretion changes the competitive relationship between species in this plant communities.

RESULTS

Among the three species (R. soongarica, Stipa glareosa and Allium polyrhizum) of the salt stressed grassland ecosystem, the conductivity of R. soongarica rhizosphere soil was the highest in five soil layers (0-55 cm depth). The high soil conductivity can increase the daily salt secretion rate of plant leaves of R. soongarica. In addition, we found the canopy size of R. soongarica was positively related to the distance from S. glareosa or A. polyrhizum. The salt-tolerance of R. soongarica was significantly higher than the other two herbs (S. glareosa and A. polyrhizum). Moreover, there was a threshold (600 µS/cm) for interspecific competition of plants mediated by soil conductivity. When the soil conductivity was lower than 600 µS/cm, the relative biomass of R. soongarica increased with the soil conductivity increase.

CONCLUSIONS

The efficient salt secretion ability of leaves increases soil conductivity under the canopy. This leads the formation of a "saline island" of R. soongarica. Meanwhile R. soongarica have stronger salt tolerance than S. glareosa and A. polyrhizum. These promote the competitiveness of R. soongarica and inhibit interspecies competition advantage of the other two herbs (S. glareosa and A. polyrhizum) in the plant community. It is beneficial for R. soongarica to establish dominant communities in saline regions of desert grassland.

Practical Assessment of the Tradeoff between Fatal Bleeding and Coronary Thrombotic Risks using the Academic Research Consortium for High Bleeding Risk Criteria

Aims: We aimed to establish a practical method for the assessment of tradeoff between thrombotic and bleeding risks.

Methods: We aimed to investigate the balance between bleeding risk and coronary thrombotic risk according to the number of the Academic Research Consortium for high bleeding risk (ARC-HBR) criteria in the multicenter prospective ST/non-ST elevation myocardial infarction (STEMI/NSTEMI) registry (N=12,093). Patients were divided as follows by the number of ARC-HBR criteria fulfilled: group 0, 0 major with ≤ 1 minor (N=6,792); group 1, 1 major with 0 minor (N=1,705); group 2, 0 major with ≥ 2 minors (N=790); group 3, 1 major with ≥ 1 minor (N=1,709); group 4, 2 majors with ≥ 0 minors (N=861); and group 5, ≥ 3 majors with ≥ 0 minor (N=236). We assessed the acute-phase absolute risk differences between bleeding and coronary thrombotic events in each group.

Results: At 7-day follow-up, all patients (groups 0–5) had a higher risk of major bleeding than that of any myocardial infarction (MI). Patients at ARC-HBR (groups 1–5) had a balanced risk between fatal MI and fatal bleeding, whereas patients at non-ARC-HBR (group 0) had a higher risk of fatal MI than that of fatal bleeding.

Conclusions: All STEMI/NSTEMI patients have a relatively high risk of major bleeding as compared with the risk of any MI in the acute phase. The ARC-HBR criteria would be a practical tool for assessing the tradeoff between fatal bleeding and fatal MI risks. This practical assessment would be helpful for the optimal decision-making of appropriate treatment strategy considering the balance between bleeding and coronary thrombotic risks.

Optimal Bayesian hierarchical model to accelerate the development of tissue-agnostic drugs and basket trials

Tissue-agnostic trials and basket trials enroll patients based on their genetic biomarkers, not tumor type, in an attempt to determine if a new drug can successfully treat disease conditions based on biomarkers. The Bayesian hierarchical model (BHM) provides an attractive approach to design phase II tissue-agnostic trials by allowing information borrowing across multiple disease types. In this article, we elucidate two intrinsic and inevitable issues that may limit the use of BHM to tissue-agnostic trials: sensitivity to the prior specification of the shrinkage parameter and the competing "interest" among disease types in increasing power and controlling type I error. To address these issues, we propose the optimal BHM (OBHM) and clustered OBHM (COBHM) approaches. In these approach, we first specify a flexible utility function to quantify the tradeoff between type I error and power across disease types based on the study objectives, and then we select the prior of the shrinkage parameter to optimize the utility function of clinical and regulatory interest. COBHM further utilizes a simple Bayesian rule to cluster tumor types into sensitive and insensitive subgroups to achieve more accurate information borrowing. Simulation study shows that the OBHM and especially COBHM have desirable operating characteristics, outperforming some existing methods. COBHM effectively balances power and type I error, addresses the sensitivity of the prior selection, and reduces the "unwarranted" subjectivity in the prior selection. It provides a systematic, rigorous way to apply BHM and solve the common problem of blindingly using a non-informative inverse-gamma prior (with a large variance) or priors arbitrarily chosen that may lead to problematic statistical properties.

Synergies and tradeoffs among Sustainable Development Goals across boundaries in a metacoupled world

Synergies and tradeoffs among the United Nations Sustainable Development Goals (SDGs) within specific locations have been widely studied. However, there is little understanding of SDG synergies and tradeoffs across spatial/administrative boundaries although the world is increasingly interconnected and the United Nations aims to achieve SDGs everywhere by 2030. To fill such an important gap, we introduce a new theoretical framework and develop a general procedure of applying the framework to empirically evaluate SDG synergies and tradeoffs within and across boundaries, based on the concept of metacoupling. We work through our framework using the examples of tourism and panda loans between the globally important Wolong Nature Reserve for panda conservation and the rest of the world to evaluate their effects on six SDGs in Wolong and the other 66 panda reserves. Our analyses uncover a total of 17 synergies and two tradeoffs, of which 10 synergies and one tradeoff are internal to Wolong, while seven synergies and one tradeoff occur across reserve boundaries. Given the first empirical evidence about cross-boundary synergies and tradeoffs, it is our hope that this study provides a foundation for further research to reveal more SDG synergies and tradeoffs across boundaries worldwide. The findings will be essential to enhance SDG synergies and reduce tradeoffs across boundaries for achieving SDGs everywhere.

Testosterone as a mediator of the tradeoff between cooperation and competition in the context of cooperative reproductive behaviors

Behavioral tradeoffs occur when the expression of one behavior detracts from the expression of another. Understanding the proximate mediators of behavioral tradeoffs is important as these tradeoffs can act as potential constraints on evolutionary responses to selection. Here, we describe the tradeoff between cooperation and competition faced by species that exhibit cooperative reproductive behaviors and propose that testosterone is a key hormonal mediator of the tradeoff. Cooperative reproductive behaviors occur when multiple individuals coordinate their efforts to gain a reproductive advantage over other individuals and/or those individuals attempting to reproduce in absence of cooperation. We propose that testosterone, a sex steroid known to mediate a number of physiological and behavioral actions associated with reproductive competition, is involved in mediating the tradeoff between cooperation and competition. To support this proposition, we first describe the importance of individual variation in behavior to the evolution of cooperative behaviors. We then describe how proximate mechanisms represent a prominent source of individual variation in social behaviors and highlight evidence suggesting testosterone mediates variation in cooperative behaviors. Two case studies in which the relationship between testosterone and cooperative behaviors have been investigated in detail are then summarized. Throughout we highlight the importance of studying individual variation to understand the mechanistic basis of behaviors, behavioral tradeoffs, and the evolution of cooperative reproductive behaviors more broadly.

Predation experience underlies the relationship between locomotion capability and survival

The positive relationship between locomotion performance and survival under predation has long been suggested yet seldom demonstrated with direct evidence. We investigate the effects of predator exposure on locomotion capacity (both fast-start escape and critical swimming performance), survival under predation and the relationships between these factors in juvenile Chinese bream (Parabramis pekinensis). This study aims to test whether there is a positive relationship between the above factors and whether such relationships are context dependent (i.e., with or without 20 d of predator exposure). We found that predator-exposed Chinese bream showed higher rates of survival under predation and improved fast-start swimming performance compared with individuals not exposed to predation. At individual level, no relationship was found between survival and any locomotion performance component in the no-predator group, but mean fast-start swimming speed, maneuverability and responsiveness were all positively related to survival in the predator group after 20 d of exposure. This finding indicates that the recognition of and vigilance for predators achieved through predation experience can be crucial preconditions for prey to employ the fast-start escape response, especially to escape ambush predators. Furthermore, a tradeoff was observed between the critical and fast-start swimming performances in the predator group, but not in the no-predator group, which may have been due to the intensified competition throughout the entire locomotion-support system (e.g., energy, proportions of slow- and fast-twitch muscle fibers) between critical and fast-start swimming because the increased demand for fast-start escape capacity constrains (or compromises) critical swimming performance under the threat of predation.

Effective leg stiffness of animal running and the co-optimization of energetic cost and stability

The relative leg stiffness of most running animals falls in a small range between 7 and 27. Here we present a theoretical study of an established running model, an actuated Spring Loaded Inverted Pendulum model, to determine if the energetic cost and stability of running might be co-optimized over this range of leg stiffness values. The energetic cost of the model is quantified as the energy spent to move a unit mass a unit distance. The stability of the model is based on the system response to perturbations with respect to periodic locomotion solutions, and uses the linearized dynamics of Poincaré return maps and the resulting maximum eigenvalue and singular value decomposition in order to analyze asymptotic stability and the overall system response to perturbations, respectively. We find that there exists a tradeoff between stability and energetic cost in the model with respect to variation in forcing (actuation) level: For a given leg stiffness, the energetic cost tends to be more optimal with smaller forcing, and the opposite for stability. We find that intermediate levels of forcing can achieve near asymptotic stability or complete asymptotic stability while remaining small enough to yield a relatively low energetic cost consistent with human-like values. We demonstrate that this outcome can be achieved in the model with a simple optimization function that balances stability and energetic cost. We then investigate the stability and energetic cost when both leg stiffness and forcing are varied. Overall, the analysis shows that leg stiffness values in or near the biological range offers a good chance of simultaneously achieving both reasonable energetic cost and stability in the model. The results of this study suggest that stability and energetic cost may be interacting factors that have a combined influence on the effective leg stiffness and actuation (forcing) used by running animals.

Considering mean and inequality health outcomes together: the population health performance index

Background

The purpose was to develop and test a population health measure that combines mean health outcomes and inequalities into a single GDP-like metric to help policymakers measure population health performance on both dimensions in one metric.

Methods

The Population Health Performance Index is a weighted average of a mean index and an inequality index according to the user’s inequality aversion. We deploy this methodology for two combinations of health outcome and disparity domain: infant mortality by race and unhealthy days by education.

Results

The PHPI is bounded between 0 and 1, and is comprised of a weighted average of two separate indices: a mean index and an inequality index, with 1 representing the ideal state of no ill health and no inequality and 0 representing the worst state in the U.S. PHPI values across states (neutral 50:50 weighting) vary between 0.60 (Massachusetts) to 0.17 (Delaware) for infant mortality by race and between 0.65 (North Dakota) to 0.00 (West Virginia) for unhealthy days by education. For some states, the choice of inequality aversion significantly impacts their PHPI value and state rank.

Conclusions

Mean and inequality health outcomes can be combined into a single Population Health Performance Index for use by public and private policy makers, like the GDP is used as a summary metric to measure economic output. The index can allow for varying degrees of inequality aversion, an individual’s or jurisdiction’s value choice that can substantially impact the value of this new summary population health metric.

Intrinsic tradeoff between kinetic and energetic efficiencies in membrane capacitive deionization

Significant progress has been made over recent years in capacitive deionization (CDI) to develop novel system configurations, predictive theoretical models, and high-performance electrode materials. To bring CDI to large scale practical applications, it is important to quantitatively understand the intrinsic tradeoff between kinetic and energetic efficiencies, or the relationship between energy consumption and the mass transfer rate. In this study, we employed both experimental and modeling approaches to systematically investigate the tradeoff between kinetic and energetic efficiencies in membrane CDI (MCDI). Specifically, we assessed the relationship between the average salt adsorption rate and specific energy consumptions from MCDI experiments with different applied current densities but a constant effluent salinity. We investigated the impacts of feed salinity, diluted water salinity, diluted water volume per charging cycle, and electrode materials on the kinetics-energetics tradeoff. We also demonstrate how this tradeoff can be employed to optimize the design and operation of CDI systems and compare the performance of different electrode materials and CDI systems.

Scale effect on spatial patterns of ecosystem services and associations among them in semi-arid area: A case study in Ningxia Hui Autonomous Region, China

Identifying scale effect on spatial patterns of ecosystem services and associations among them has been recognized as critical to the sustainable management of ecosystem services. We proposed a method to conveniently integrate ecosystem services of small scale into different larger scales. Taking Ningxia Hui Autonomous Region in west China as an example, we analyzed the change regularity of spatial patterns of 7 ecosystem services under 22 different scales. Further, the tradeoffs and synergies among ecosystem services across all scales were compared. The results showed that all of the 7 ecosystem services had been characterized by stable spatial cluster patterns across all of the 22 scales in our study. However, the extent of aggregation decreased with the increase of scale owing to the 'peak cutting and valley filling' process of map scale synthesis. Most of the associations among ecosystem services were robust across scales. However, there was a trend that smaller scales had more pairwise correlations than larger scales. The formation of tradeoffs and synergies among ecosystem services can be attributed to one or more of the following three factors: land use conflict or consistency, common drivers, and interactions among ecosystem services. We attribute the change of relationships among ecosystem services with scales to that the role of factors causing tradeoffs and synergies among ecosystem services may change with scales. Food supply service synergizes with all of the 3 regulating services at almost all of the scales in our study area, indicating that well managed farmlands with high net profit are beneficial to soil conservation and organic matter accumulation in semi-arid area.

Using palaeolimnological data and historical records to assess long-term dynamics of ecosystem services in typical Yangtze shallow lakes (China)

Understanding the dynamics of ecosystem services (ESs) is crucial for sustainable resource management. Palaeolimnological records have a great potential to reveal long-term variations and dynamic interactions in ESs, especially supporting/regulating services, which are not easily quantified by documentary records. To elucidate the variations between eight important ESs in shallow lake ecosystems, we combined documentary records with palaeolimnological proxies (covering the past 100years) from two typical lakes (Lakes Taibai and Zhangdu) of the Yangtze River basin. Although all supporting services and some provisioning services have increased, the regulating services of the two lakes have markedly declined, in particular since the 1950s. Human activities, including hydrological intervention, nutrient input and land-use change, were identified as the main factors behind the observed variations. Both in Lake Taibai and Zhangdu, primary production and biodiversity (supporting services) have increased (synergies), whereas climate and water purification (regulating services) have significantly decreased (tradeoffs) since the 1950s when attempts were made by the local population to reach a higher land/fish ESs level. By considering long-term records, dynamic tradeoff and synergy relationship between various ESs relative to different types of human "modification" in a temporal perspective, we suggest valuable information can be gained in future lake management initiatives.

Cellular oxidative damage is more sensitive to biosynthetic rate than to metabolic rate: A test of the theoretical model on hornworms (Manduca sexta larvae)

We develop a theoretical model from an energetic viewpoint for unraveling the entangled effects of metabolic and biosynthetic rates on oxidative cellular damage accumulation during animal's growth, and test the model by experiments in hornworms. The theoretical consideration suggests that most of the cellular damages caused by the oxidative metabolism can be repaired by the efficient maintenance mechanisms, if the energy required by repair is unlimited. However, during growth a considerable amount of energy is allocated to the biosynthesis, which entails tradeoffs with the requirements of repair. Thus, the model predicts that cellular damage is more influenced by the biosynthetic rate than the metabolic rate. To test the prediction, we induced broad variations in metabolic and biosynthetic rates in hornworms, and assayed the lipid peroxidation and protein carbonyl. We found that the increase in the cellular damage was mainly caused by the increase in biosynthetic rate, and the variations in metabolic rate had negligible effect. The oxidative stress hypothesis of aging suggests that high metabolism leads to high cellular damage and short lifespan. However, some empirical studies showed that varying biosynthetic rate, rather than metabolic rate, changes animal's lifespan. The conflicts between the empirical evidence and the hypothesis are reconciled by this study.

Plasticity of immunity in response to eating

Following a meal, an animal can exhibit dramatic shifts in physiology and morphology, as well as a substantial increase in metabolic rate associated with the energetic costs of processing a meal (i.e. specific dynamic action, SDA). However, little is known about the effects of digestion on another important physiological and energetically costly trait: immune function. Thus, we tested two competing hypotheses. (1) Digesting animals up-regulate their immune systems (putatively in response to the increased microbial exposure associated with ingested food). (2) Digesting animals down-regulate their immune systems (presumably to allocate energy to the breakdown of food). We assayed innate immunity (lytic capacity and agglutination) in cornsnakes (Pantherophis guttatus) during and after meal digestion. Lytic capacity was higher in females, and (in support of our first hypothesis) agglutination was higher during absorption. Given its potential energetic cost, immune up-regulation may contribute to SDA.

Patient preference and decision-making for initiating metastatic colorectal cancer medical treatment

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.

Compensating wage differentials and the impact of health insurance in the public sector on wages and hours

This paper examines the trade-off between wages and employer spending on health insurance for public sector workers, and the relationship between coverage and hours worked. Our primary approach compares trends in wages and hours for public employees with and without state/local government provided health insurance using individual-level micro-data from the 1992-2011 CPS. To adjust for differences between insured and uninsured public sector employees, we create a matched sample based on an employee's propensity to receive health insurance. We assess the relationship between state contribution to the health plan premium, state-level healthcare spending, and the wages and hours of state and local government employees. We find modest reductions in wages are associated with having employer-sponsored health insurance (ESHI), although this effect is not precisely measured. The reduction in wages associated with having ESHI is larger among non-unionized workers. Further, we find little evidence that provision of health insurance increases hours worked.

Optimizing the dammed: water supply losses and fish habitat gains from dam removal in California

Dams provide water supply, flood protection, and hydropower generation benefits, but also harm native species by altering the natural flow regime and degrading aquatic and riparian habitat. Restoring some rivers reaches to free-flowing conditions may restore substantial environmental benefits, but at some economic cost. This study uses a systems analysis approach to preliminarily evaluate removing rim dams in California's Central Valley to highlight promising habitat and unpromising economic use tradeoffs for water supply and hydropower. CALVIN, an economic-engineering optimization model, is used to evaluate water storage and scarcity from removing dams. A warm and dry climate model for a 30-year period centered at 2085, and a population growth scenario for year 2050 water demands represent future conditions. Tradeoffs between hydropower generation and water scarcity to urban, agricultural, and instream flow requirements were compared with additional river kilometers of habitat accessible to anadromous fish species following dam removal. Results show that existing infrastructure is most beneficial if operated as a system (ignoring many current institutional constraints). Removing all rim dams is not beneficial for California, but a subset of existing dams are potentially promising candidates for removal from an optimized water supply and free-flowing river perspective. Removing individual dams decreases statewide delivered water by 0-2282 million cubic meters and provides access to 0 to 3200 km of salmonid habitat upstream of dams. The method described here can help prioritize dam removal, although more detailed, project-specific studies also are needed. Similarly, improving environmental protection can come at substantially lower economic cost, when evaluated and operated as a system.

Increased allocation of adult-acquired carbohydrate to egg production results in its decreased allocation to sex pheromone production in mated females of the moth Heliothis virescens

Females of most species of moths produce a volatile sex pheromone that attracts conspecific males over distance. In females of the polyandrous moth Heliothis virescens, feeding on carbohydrate (e.g. nectar) supplies precursor, via hemolymph trehalose, for both sex pheromone and egg production. With limited carbohydrate acquisition these two reproductive physiologies might compete for hemolymph trehalose, resulting in an allocation deficit to either sex pheromone or egg production. Using virgin and mated females, which have low and high egg maturation rates, respectively, we fed females a limited diet of (13)C-labeled glucose daily and, using mass isotopomer distribution analysis, determined allocations of adult-acquired carbohydrate (AAC) to newly synthesized pheromone and ovarian and egg fats, our proxies for allocation to egg production. With increased number of feeds, AAC enrichment of hemolymph trehalose increased, as expected. This led to mated females increasing their proportional allocation of AAC to ovarian and egg fats, but decreasing their proportional allocation of AAC to pheromone production. By contrast, virgins increased their proportional allocation of AAC to pheromone production with increased feeds, consistent with increasing AAC enrichment of hemolymph trehalose. These results show that with limited AAC intake, enhanced egg maturation in mated females results in reduced AAC allocation to pheromone production; this does not occur in virgins because of their lower egg maturation rate. This physiological competition for AAC corresponded with decreased pheromone production in mated moths to levels unlikely to attract mates. Therefore, the availability and/or allocation of AAC may be a proximate mechanism underlying the incidence of polyandry in this and other species of moths.

Interacting effects of predation risk and food availability on larval anuran behaviour and development

Age and size at metamorphosis are two important fitness components in species with complex life cycles. In anurans, metamorphic traits show remarkable phenotypic plasticity, especially in response to changes in growth conditions. It is also possible that the perception of risk directly determines changes in larval period and the size of metamorphs. This study examines how the perception of predation risk affects the timing of and size at metamorphosis in common frogs (Rana temporaria). I raised tadpoles at two risk levels (fish-conditioned water or unconditioned water) crossed with the availability or lack of food at night (all tadpoles had food available in the day). Tadpoles reacted to chemical cues from predatory fish by decreasing activity. A novel behavioural result was a predation×food interaction effect on refuge use, which also accounted for most of the predator main effect: predation risk only caused increased refuge use in the night-starved treatment. Despite these behavioural modifications, the perception of predation risk did not affect growth rate and mass at metamorphosis in a simple way: the effects of food regime on growth and size at metamorphosis were dependent on the level of predation risk as revealed by significant predation×food interaction effects. Tadpoles who had food withheld at night metamorphosed at the smallest size, suggesting a negative relationship between size at metamorphosis and refuge use. Tadpoles raised in fish-conditioned water had longer larval periods than those in unconditioned water, but these differences were significant only if food was available at night. These results conflict with the hypotheses that tadpoles should reduce their larval period or growth rates (and hence metamorphose at a smaller size) as the risk of predation increases. In contrast to predation risk, food availability strongly affected the length of the larval period: night-starved tadpoles metamorphosed relatively early with or without fish stimulus. Thus, early metamorphosis resulted from periods of low food availability, but not from a heightened "perceived risk" of predation. This example counters the hypothesis of acceleration of the developmental rate (which shortens the time to metamorphosis) as a mechanism to escape a risky environment.