Critical Data Gaps Research Articles

Understanding Climate‐Hydrologic‐Human Interactions to Guide Groundwater Model Development for Southern High Plains

AbstractThe Ogallala Aquifer is the only reliable source of freshwater in the Southern High Plains (SHP) and is used extensively to build a strong agricultural economy with a significant impact on global food security. Groundwater models capable of simulating human‐hydrologic‐climate interactions are crucial to guide future water management and policy planning endeavors in this water stressed region. A well‐defined conceptual model is a necessary first‐step in that direction. Conceptual modeling should not be limited to compiling necessary datasets but must also focus on generating critical insights pertaining to human‐climate‐aquifer interactions especially when the emphasis is on guiding future policy. Model integration and the feasibility of coupling available tools and techniques must be explored to fill‐in critical data gaps and capture interactions with a high degree of fidelity. A conceptual modeling framework built on this premise was applied to guide an on‐going regional‐scale groundwater modeling study in the SHP. The paucity of groundwater production data was identified as a major limiting factor. A linked Decision Support System for Agro‐Technology Transfer (DSSAT) model with MODFLOW is expected to be useful in obtaining groundwater production estimates through detailed crop modeling. The time to recharge is long (decades to centuries) over most of the SHP. As such, the coupling of watershed and groundwater models is perhaps not warranted. Baseflow separation indicated that surface water‐groundwater interactions have diminished over the last six decades due to declining water tables. While groundwater withdrawals generally increased during droughts, the aquifer also buffered climatic influences at some locations.

Vitamin D: Moving Forward to Address Emerging Science.

The science surrounding vitamin D presents both challenges and opportunities. Although many uncertainties are associated with the understandings concerning vitamin D, including its physiological function, the effects of excessive intake, and its role in health, it is at the same time a major interest in the research and health communities. The approach to evaluating and interpreting the available evidence about vitamin D should be founded on the quality of the data and on the conclusions that take into account the totality of the evidence. In addition, these activities can be used to identify critical data gaps and to help structure future research. The Office of Dietary Supplements (ODS) at the National Institutes of Health has as part of its mission the goal of supporting research and dialogues for topics with uncertain data, including vitamin D. This review considers vitamin D in the context of systematically addressing the uncertainty and in identifying research needs through the filter of the work of ODS. The focus includes the role of systematic reviews, activities that encompass considerations of the totality of the evidence, and collaborative activities to clarify unknowns or to fix methodological problems, as well as a case study using the relationship between cancer and vitamin D.

Assessing Irrigation Aquifer Depletion: Introduction

Assessing Irrigation Aquifer Depletion: Introduction

The Comprehensive Barnegat Bay Research Program

Abstract Buchanan, G.A.; Belton, T.J., and Paudel, B., 2017. The Comprehensive Barnegat Bay Research Program. In: Buchanan, G.A.; Belton, T.J., and Paudel, B. (eds.), A Comprehensive Assessment of Barnegat Bay-Little Egg Harbor, New Jersey. A comprehensive ecosystem research strategy was developed and initiated for the Barnegat Bay-Little Egg Harbor (BB-LEH) estuary in New Jersey, United States. This multiyear program (2011–15) examined several environmental management issues and questions involving concerns with water quality (e.g., nutrients) and the health of this ecosystem (e.g., eutrophication). Multiple projects ranging from the assessment of phytoplankton to fish to wetlands, as well as hydrodynamic/water quality and ecosystem modeling, were conducted each year to fill in critical data gaps and to define the bay's baseline condition for future comparisons (e.g., a nuclear generating station on the bay with a once-through cooling system will close in 2019). Issues of concern for environmental agenci...

Urban Nexus Science for Future Cities: Focus on the Energy-Water-Food-X Nexus

Rapid urban expansion of the world’s cities is placing unprecedented demands on the energy, water, food, and other (X) systems (e.g., mobility) that each offer multiple life-supporting services. Coordination that considers inter-sectoral connections among these urban systems and services remains nascent in practice, yet are critical to the future well-being, resource/operational efficiency, and resilience of urban areas. This paper therefore proposes an applied “urban nexus science” framework to identify integrated and synergistic pathways toward achieving urban sustainability. The design, planning, and operation of urban W-E-F systems can benefit from integrated analyses to accelerate infrastructure, land use, and hazard mitigation planning and decision-making. New knowledge quantifying the key effects of W-E-F systems designed in isolation versus an increasingly integrated systems, especially when exposed to hazards, health risks, or extreme events, are a critical need. Interactive system modeling and participatory technologies are needed to support stakeholder engagement and two-way (and multi-directional) information flow, for exploring outcomes of alternative solutions for integrating W-E-F sectors. To support such important efforts, research is needed to fill critical gaps in data, identify tradeoffs, and develop synergistic solutions that measure sustainability co-benefits based on different levels of urban integration among W-E-F systems and services.

An Economic Evaluation of Food Safety Education Interventions: Estimates and Critical Data Gaps

The economic evaluation of food safety interventions is an important tool that practitioners and policy makers use to assess the efficacy of their efforts. These evaluations are built on models that are dependent on accurate estimation of numerous input variables. In many cases, however, there is no data available to determine input values and expert opinion is used to generate estimates. This study uses a benefit-cost analysis of the food safety component of the adult Expanded Food and Nutrition Education Program (EFNEP) in Ohio as a vehicle for demonstrating how results based on variable values that are not objectively determined may be sensitive to alternative assumptions. In particular, the focus here is on how reported behavioral change is translated into economic benefits. Current gaps in the literature make it impossible to know with certainty how many people are protected by the education (what are the spillover effects?), the length of time education remains effective, and the level of risk reduction from change in behavior. Based on EFNEP survey data, food safety education led 37.4% of participants to improve their food safety behaviors. Under reasonable default assumptions, benefits from this improvement significantly outweigh costs, yielding a benefit-cost ratio of between 6.2 and 10.0. Incorporation of a sensitivity analysis using alternative estimates yields a greater range of estimates (0.2 to 56.3), which highlights the importance of future research aimed at filling these research gaps. Nevertheless, most reasonable assumptions lead to estimates of benefits that justify their costs.

Food Security As Peacebuilding: Analyzing the Relationship between Food Security and Conflict Data to Support Empirical Policy Making

During the previous decade there has been an increased focus on the role of food security in conflict processes, both in the academic and policy communities. While the policy community has pushed forward with new programs, the causal linkages between food security and conflict remain debated and not well understood. This article emphasizes the endogeneity that characterizes the coupling between food (in)security and violent conflict. We make three contributions. First, we operationalize conflict and food security using the standard Uppsala Conflict Data Program and the FAO databases, and illustrate how intervening factors influence the relationships between conflict and food security at the micro and macro levels. Second, we provide a comprehensive review of the literature on the linkages between food security and conflict, focusing on findings that account for endogeneity issues and have a causal interpretation. Third, we highlight critical data gaps impeding learning and policy-making and discuss chart ways forward of improving and extending the existing data base, and opportunities for innovation in food security and peacebuilding.

Detection of 3,3'-Dichlorobiphenyl in Human Maternal Plasma and Its Effects on Axonal and Dendritic Growth in Primary Rat Neurons.

3,3'-Dichlorobiphenyl (PCB 11), a byproduct of pigment production, is increasingly detected in environmental samples. While more highly chlorinated PCB congeners are known developmental neurotoxicants, nothing is known about the potential developmental neurotoxicity of PCB 11. To address this critical data gap, we measured PCB 11 levels in human maternal plasma and quantified the effects of PCB 11 and its major metabolites on morphometric parameters of neuronal connectivity in cultured primary neurons. Mass spectrometry analyses of plasma from 241 pregnant women enrolled in the MARBLES study (University of California, Davis) detected PCB 11 in all samples at concentrations ranging from 0.005 to 1.717 ng/ml. Morphometric analyses of primary neuron-glia co-cultures dissociated from the neocortices or hippocampi of neonatal Sprague Dawley rats exposed to vehicle or concentrations ranging from 1attamolar (aM) to 1micromolar (µM) of PCB 11, OH-PCB 11, or PCB 11 sulfate indicated that PCB 11 and both metabolites significantly increased axonal and dendritic growth in cortical and hippocampal pyramidal neurons. PCB 11 significantly altered neuronal morphogenesis at concentrations as low as 1femtomolar (fM), which is ∼0.22 ng/ml. These data suggest the potential for the developing human brain to be exposed to PCB 11, and demonstrate that environmentally relevant levels of PCB 11 alter axonal and dendritic growth in neuronal cell types critically involved in cognitive and higher-order behaviors. These findings identify PCB 11 as a potential environmental risk factor for adverse neurodevelopmental outcomes in humans.

Long-Term Land Cover Data for the Lower Peninsula of Michigan, 2010–2050

Land cover data are often used to examine the impacts of landscape alterations on the environment from the local to global scale. Although various agencies produce land cover data at various spatial scales, data are still limited at the regional scale over extended timescales. This is a critical data gap since decision-makers often use future and long-term land cover maps to develop effective policies for sustainable environmental systems. As a result, land change science incorporates common data mining tools to create future land cover maps that extend over long timescales. This study applied one of the well-known land cover change models, called Land Transformation Model (LTM), to produce urbanization maps for the Lower Peninsula of Michigan in United States from 2010 to 2050 with five year intervals. Long-term urbanization data in the Lower Peninsula of Michigan can be used in various environmental studies such as assessing the impact of future urbanization on climate change, water quality, food security and biodiversity.

Securing sustainable and nutritious food systems through mainstreaming agricultural biodiversity: an interdisciplinary study

BackgroundUrgent reform of our food systems is needed if they are to provide high quality nourishment and at the same time protect the environment. Agriculture, food systems, and diets have been greatly simplified over the past century. Policies and investments have been too focused on maximising productivity and economic returns of a few major staples. So much so that global production of fruits, vegetables, nuts, and seeds falls way short of what is required globally. Agricultural and food policies and actions have become disconnected from nutrition policies and programmes, calling for urgent realignment of food systems to focus on nourishing people while sustaining the planet. Focusing in Brazil and India, our work aimed to show that sustainable solutions for transforming food systems are indeed possible. MethodsIn Brazil, nutritional composition analysis of 65 prioritised native fruit species was carried out in partnership with several public universities and research institutes using FAO/INFOODS methodologies with data made available through a National Composition Database within the Information System on Brazilian Biodiversity (SiBBr). In India, participatory variety selection, improved cultivation practices, value addition, and marketing and public awareness campaigns were tackled along with capacity building of local community members. Lobbying for millets supportive policies was pursued at state and national level. FindingsIn Brazil, preliminary results indicate that many of the analysed priority native fruits are more nutritionally rich compared with the five most commonly consumed fruits. These findings were instrumental in the passing in 2016 of a new Ordinance on Sociobiodiversity, which officially recognises the nutritional value of these species and which contributes to the mainstreaming of nutritious underutilised species into relevant policies and programmes. In India, public campaigns leveraging healthy and cultural appeal of millets are creating new demand. Drudgery reduction in cultivation, availability of high quality seed and grains, and enhanced processing technology are revitalising their value chains. Successful policy advocacy contributed to the amendment of the National Food Security Act in 2013, which by introducing millets in the Public Distribution System has opened unprecedented opportunities for their nationwide popularisation. InterpretationIn Brazil, by addressing critical data gaps, these findings, and other actions, have been important in influencing the national policy landscape, especially in relation to targeting the diversification of school feeding and food procurement, as well as the development of new supporting policies such as the abovementioned ordinance on sociobiodiversity. In India, interdisciplinary and intersectorial approaches played a strategic part in removing bottlenecks hindering the use of millets. A mix of resilience, nutrition, healthy, cultural, and income generation appeal associated to these crops helped to raise their visibility among policy makers. These projects also showed that an Agrobiodiversity Index to help policymakers to decide how to use agrobiodiversity for sustainable choices in support of nutritious food systems would be a highly benefiical instrument. FundingUnited Nations Environment Programme (UNEP), International Fund for Agricultural Development (IFAD), European Union (EU).

Climatic and geographic predictors of life history variation in Eastern Massasauga (Sistrurus catenatus): A range-wide synthesis.

Elucidating how life history traits vary geographically is important to understanding variation in population dynamics. Because many aspects of ectotherm life history are climate-dependent, geographic variation in climate is expected to have a large impact on population dynamics through effects on annual survival, body size, growth rate, age at first reproduction, size–fecundity relationship, and reproductive frequency. The Eastern Massasauga (Sistrurus catenatus) is a small, imperiled North American rattlesnake with a distribution centered on the Great Lakes region, where lake effects strongly influence local conditions. To address Eastern Massasauga life history data gaps, we compiled data from 47 study sites representing 38 counties across the range. We used multimodel inference and general linear models with geographic coordinates and annual climate normals as explanatory variables to clarify patterns of variation in life history traits. We found strong evidence for geographic variation in six of nine life history variables. Adult female snout-vent length and neonate mass increased with increasing mean annual precipitation. Litter size decreased with increasing mean temperature, and the size–fecundity relationship and growth prior to first hibernation both increased with increasing latitude. The proportion of gravid females also increased with increasing latitude, but this relationship may be the result of geographically varying detection bias. Our results provide insights into ectotherm life history variation and fill critical data gaps, which will inform Eastern Massasauga conservation efforts by improving biological realism for models of population viability and climate change.

Trials Are Needed to Evaluate Nutrition Interventions for Heart Failure: An Analysis of the Federal Research Portfolio

Nutrition research has the potential to identify better ways of preventing and managing heart failure, thus reducing costs and improving patient outcomes. However, it has proved especially challenging to design well-powered clinical efficacy and effectiveness studies in this field. To better understand the federal research support provided to date on this topic and to identify issues that applicants must address, we conducted a portfolio analysis by using the federal RePORTER database. We limited the search to funded projects for the fiscal years 2000–2016 in which the terms “nutrition or diet or dietary supplements” and “heart failure” were included in the abstract, key words, or title. We found that ?70 projects were funded during this time period, the majority being supported through research project grants (R mechanisms) and a smaller number through training awards (F or K mechanisms). Most of the awards were funded by 3 NIH institutes (National Heart, Lung, and Blood Institute, National Institute of Nursing Research, and National Institute on Aging) and by the NIH Office of Dietary Supplements. The main types of funded science were basic studies in animal models and longitudinal or cross-sectional observational cohort studies. There were relatively few intervention studies, with most evaluating behavioral change and education modalities. The trials that compared dietary treatments generally were small proof-of-concept or pilot studies. Nutrition research typically comprises ?5% of the NIH research investment (e.g., $1.6–$30 billion); heart failure has a very low profile within the NIH nutrition research portfolio (e.g., ?$9 million–$1.6 billion, or 0.5% in 2016). Nutrition issues and dietary interventions are understudied in patients with heart failure. To close critical data gaps in patient management, we need well-designed efficacy and effectiveness trials linking diet with clinical outcomes.

Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): emissions of trace gases and light-absorbing carbon from wood and dung cooking fires, garbage and crop residue burning, brick kilns, and other sources

Abstract. The Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE) campaign took place in and around the Kathmandu Valley and in the Indo-Gangetic Plain (IGP) of southern Nepal during April 2015. The source characterization phase targeted numerous important but undersampled (and often inefficient) combustion sources that are widespread in the developing world such as cooking with a variety of stoves and solid fuels, brick kilns, open burning of municipal solid waste (a.k.a. trash or garbage burning), crop residue burning, generators, irrigation pumps, and motorcycles. NAMaSTE produced the first, or rare, measurements of aerosol optical properties, aerosol mass, and detailed trace gas chemistry for the emissions from many of the sources. This paper reports the trace gas and aerosol measurements obtained by Fourier transform infrared (FTIR) spectroscopy, whole-air sampling (WAS), and photoacoustic extinctiometers (PAX; 405 and 870 nm) based on field work with a moveable lab sampling authentic sources. The primary aerosol optical properties reported include emission factors (EFs) for scattering and absorption coefficients (EF Bscat, EF Babs, in m2 kg−1 fuel burned), single scattering albedos (SSAs), and absorption Ångström exponents (AAEs). From these data we estimate black and brown carbon (BC, BrC) emission factors (g kg−1 fuel burned). The trace gas measurements provide EFs (g kg−1) for CO2, CO, CH4, selected non-methane hydrocarbons up to C10, a large suite of oxygenated organic compounds, NH3, HCN, NOx, SO2, HCl, HF, etc. (up to ∼ 80 gases in all). The emissions varied significantly by source, and light absorption by both BrC and BC was important for many sources. The AAE for dung-fuel cooking fires (4.63 ± 0.68) was significantly higher than for wood-fuel cooking fires (3.01 ± 0.10). Dung-fuel cooking fires also emitted high levels of NH3 (3.00 ± 1.33 g kg−1), organic acids (7.66 ± 6.90 g kg−1), and HCN (2.01 ± 1.25 g kg−1), where the latter could contribute to satellite observations of high levels of HCN in the lower stratosphere above the Asian monsoon. HCN was also emitted in significant quantities by several non-biomass burning sources. BTEX compounds (benzene, toluene, ethylbenzene, xylenes) were major emissions from both dung- (∼ 4.5 g kg−1) and wood-fuel (∼ 1.5 g kg−1) cooking fires, and a simple method to estimate indoor exposure to the many measured important air toxics is described. Biogas emerged as the cleanest cooking technology of approximately a dozen stove–fuel combinations measured. Crop residue burning produced relatively high emissions of oxygenated organic compounds (∼ 12 g kg−1) and SO2 (2.54 ± 1.09 g kg−1). Two brick kilns co-firing different amounts of biomass with coal as the primary fuel produced contrasting results. A zigzag kiln burning mostly coal at high efficiency produced larger amounts of BC, HF, HCl, and NOx, with the halogenated emissions likely coming from the clay. The clamp kiln (with relatively more biomass fuel) produced much greater quantities of most individual organic gases, about twice as much BrC, and significantly more known and likely organic aerosol precursors. Both kilns were significant SO2 sources with their emission factors averaging 12.8 ± 0.2 g kg−1. Mixed-garbage burning produced significantly more BC (3.3 ± 3.88 g kg−1) and BTEX (∼ 4.5 g kg−1) emissions than in previous measurements. For all fossil fuel sources, diesel burned more efficiently than gasoline but produced larger NOx and aerosol emission factors. Among the least efficient sources sampled were gasoline-fueled motorcycles during start-up and idling for which the CO EF was on the order of ∼ 700 g kg−1 – or about 10 times that of a typical biomass fire. Minor motorcycle servicing led to minimal if any reduction in gaseous pollutants but reduced particulate emissions, as detailed in a companion paper (Jayarathne et al., 2016). A small gasoline-powered generator and an “insect repellent fire” were also among the sources with the highest emission factors for pollutants. These measurements begin to address the critical data gap for these important, undersampled sources, but due to their diversity and abundance, more work is needed.

High consumption of potatoes may increase risk of developing type 2 diabetes.

Commentary on: Muraki I, Rimm ER, Willett WC, et al. Potato consumption and risk of type 2 diabetes: results from three prospective cohort studies. Diabeties Care 2016;39:376–84[OpenUrl][1][CrossRef][2]. Potatoes are commonly consumed in the USA and European countries. In the USA, it accounts for ∼21% of all vegetable consumption.1 Potatoes are considered as a healthy vegetable in the National Guideline of Healthy Eating established by the Department of Agriculture2 and as an eligible vegetable by the Special Supplemental Nutrition Programme for women, infants and children by the Institute of Medicine.3 The health effects of potatoes on cardiometabolic health, however, remain inconclusive, because potatoes are high in both high glycaemic carbohydrate and potassium. To address the critical data gap, the present study by Muraki et al aimed to comprehensively and prospectively investigate the association between potato consumption and incident risk of type 2 diabetes (T2DM). The study … [1]: {openurl}?query=rft.jtitle%253DDiabeties%2BCare%26rft.volume%253D39%26rft.spage%253D376%26rft_id%253Dinfo%253Adoi%252F10.2337%252Fdc15-0547%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [2]: /lookup/external-ref?access_num=10.2337/dc15-0547&link_type=DOI

Global biodiversity monitoring: From data sources to Essential Biodiversity Variables

Essential Biodiversity Variables (EBVs) consolidate information from varied biodiversity observation sources. Here we demonstrate the links between data sources, EBVs and indicators and discuss how different sources of biodiversity observations can be harnessed to inform EBVs. We classify sources of primary observations into four types: extensive and intensive monitoring schemes, ecological field studies and satellite remote sensing. We characterize their geographic, taxonomic and temporal coverage. Ecological field studies and intensive monitoring schemes inform a wide range of EBVs, but the former tend to deliver short-term data, while the geographic coverage of the latter is limited. In contrast, extensive monitoring schemes mostly inform the population abundance EBV, but deliver long-term data across an extensive network of sites. Satellite remote sensing is particularly suited to providing information on ecosystem function and structure EBVs. Biases behind data sources may affect the representativeness of global biodiversity datasets. To improve them, researchers must assess data sources and then develop strategies to compensate for identified gaps. We draw on the population abundance dataset informing the Living Planet Index (LPI) to illustrate the effects of data sources on EBV representativeness. We find that long-term monitoring schemes informing the LPI are still scarce outside of Europe and North America and that ecological field studies play a key role in covering that gap. Achieving representative EBV datasets will depend both on the ability to integrate available data, through data harmonization and modeling efforts, and on the establishment of new monitoring programs to address critical data gaps.

THz limb sounder (TLS) for lower thermospheric wind, oxygen density, and temperature

AbstractNeutral winds are one of the most critical measurements in the lower thermosphere and E region ionosphere (LTEI) for understanding complex electrodynamic processes and ion‐neutral interactions. We are developing a high‐sensitivity, low‐power, noncryogenic 2.06 THz Schottky receiver to measure wind profiles at 100–140 km. The new technique, THz limb sounder (TLS), aims to measure LTEI winds by resolving the wind‐induced Doppler shift of 2.06 THz atomic oxygen (OI) emissions. As a transition between fine structure levels in the ground electronic state, the OI emission is in local thermodynamic equilibrium (LTE) at altitudes up to 350 km. This LTE property, together with day‐and‐night capability and small line‐of‐sight gradient, makes the OI limb sounding a very attractive technique for neutral wind observations. In addition to the wind measurement, TLS can also retrieve [OI] density and neutral temperature in the LTEI region. TLS leverages rapid advances in THz receiver technologies including subharmonically pumped (SHP) mixers and Schottky‐diode‐based power multipliers. Current SHP Schottky receivers have produced good sensitivity for THz frequencies at ambient environment temperatures (120–150 K), which are achievable through passively cooling in spaceflight. As an emerging technique, TLS can fill the critical data gaps in the LTEI neutral wind observations to enable detailed studies on the coupling and dynamo processes between charged and neutral molecules.

Novel correlates between antimüllerian hormone and menstrual cycle characteristics in African-American women (23–35 years-old)

To characterize normative antimüllerian hormone (AMH) levels and ascertain which factors are associated with AMH inalarge cohort of reproductive-age women. Cross-sectional study. Not applicable. A total of 1,654 African-American women (AAW) ages 23-34 at recruitment. Not applicable. Serum AMH measured using an ultrasensitive ELISA. The median AMH was 3.18ng/mL, and there was a significant, but nonlinear, relationship between age and AMH, with levels peaking at age 25. As AMH was not normally distributed, log transformation was performed and used for all analyses. In a multivariable age-adjusted model, body mass index, current use of hormonal contraception, and history of a thyroid condition were inversely associated with AMH, while history of abnormal menstrual bleeding and menstrual cycles longer than 35days were positively associated with AMH. While age is correlated with AMH, it accounts for only a portion of the variation seen. This study adds valuable information to the existing literature on normative AMH levels in young reproductive-age women. While our findings fill a critical data gap for ovarian reserve in AAW, the insights gained will be of benefit for all women.

Data integration, reservoir response, and application

The microseismic activity observed in and around a geologic formation undergoing carbon dioxide (CO2) injection is a combination of natural, or “background”, microseismicity plus that activity which is induced by injection operations. Since injection pressure within storage target formations are maintained safely below fracture pressure this induced activity typically originates at natural pre-existing zones of mechanical weakness presented by structural or stratigraphic features. The combination of mechanical properties and in situ stresses dictate the focal mechanism for microseismic emissions, an understanding of which facilitates the use of observed microseismicity for regulatory compliance and project management.Under favorable conditions microseismic activity may be unambiguously correlated with structural and/or stratigraphic features directly observed in seismic data, thus providing strong constraints to interpretation of observed microseismicity for focal mechanisms. However, in many cases, such as at the Illinois Basin–Decatur Project (IBDP), this direct correlation is elusive and other indirect support is required. Analysis of microseismicity at IBDP has been performed within the context of the integrated reservoir and mechanical earth models developed as part of the site characterization and monitoring program. The IBDP integrated modeling workflow involved continuous and geotechnically consistent data integration for geologic modeling, calibrated flow simulation, three-dimensional (3D) mechanical earth model, and coupled hydro-mechanical simulation. Using the coupled model, scenario-based forward modeling of microseismicity was performed for hypothetical focal mechanisms inferred from observed data.The experience gained at IBDP illustrates the importance of integrated modeling in the interpretation of microseismic activity for focal mechanisms and provides valuable insights into critical data gaps which could be the target of future basic research efforts.

Reconstructing exposures from biomarkers using exposure-pharmacokinetic modeling – A case study with carbaryl

Sources of uncertainty involved in exposure reconstruction for short half-life chemicals were characterized using computational models that link external exposures to biomarkers. Using carbaryl as an example, an exposure model, the Cumulative and Aggregate Risk Evaluation System (CARES), was used to generate time-concentration profiles for 500 virtual individuals exposed to carbaryl. These exposure profiles were used as inputs into a physiologically based pharmacokinetic (PBPK) model to predict urinary biomarker concentrations. These matching dietary intake levels and biomarker concentrations were used to (1) compare three reverse dosimetry approaches based on their ability to predict the central tendency of the intake dose distribution; and (2) identify parameters necessary for a more accurate exposure reconstruction. This study illustrates the trade-offs between using non-iterative reverse dosimetry methods that are fast, less precise and iterative methods that are slow, more precise. This study also intimates the necessity of including urine flow rate and elapsed time between last dose and urine sampling as part of the biomarker sampling collection for better interpretation of urinary biomarker data of short biological half-life chemicals. Resolution of these critical data gaps can allow exposure reconstruction methods to better predict population-level intake doses from large biomonitoring studies.

Key factors controlling the real exhaust emissions from earthwork machines

This study focuses on the actual exhaust emissions of regulated and unregulated pollutants from earthwork machines (EM). In addition to providing a realistic assessment of gaseous and particulate emissions from key EM and filling critical data gaps in emission inventories, it emphasizes the importance of breaking down the average operating emission factors into task-related emission factors (TEF). The latter serve many goals, namely by: categorizing EM in relation to their emission dynamics, finding emission determinants and proposing on-site emission mitigation strategies. These have also led to a more refined analysis of both the effectiveness of EU and US emissions standards and the accuracy of NONROAD2008 model. Ultimately, by using task-related emission factors in conjunction with data available from the literature and with the methodology developed by US-EPA, a lower bound was estimated for gaseous exhaust emissions from the major construction vehicles operable at earthwork sites.