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Addressing the 'wicked problem' of nutrient pollution requires coordinated policies spanning across diverse sectors and environmental systems. Using a case study of Canadian legislation, we apply semantic network analysis to identify thematic links across an inventory of 245 nutrient-related policies. Our analysis identifies twelve topics with unique types of connections across multiple facets of Canadian society. 'Hub' policies include broad environmental protection, land use planning, and climate-related legislation with close ties to multiple other topics. 'Bridge' policies create connections among otherwise disconnected topics in the network, representing opportunities to inform new policy proposals. Some legislation, such as food processing regulations, indirectly relates to nutrient use but could inform policy integration towards more coordinated and holistic nutrient management across the food system. A computational text network approach can be useful for addressing challenges in complex policy analysis, including by identifying unique entry points to guide more cross-cutting nutrient policy development. [ABSTRACT FROM AUTHOR]

The global food system, and animal agriculture in particular, is a major and growing contributor to climate change, land system change, biodiversity loss, water consumption and contamination, and environmental pollution. The copious production and consumption of animal products are also contributing to increasingly negative public health outcomes, particularly in wealthy and rapidly industrializing countries, and result in the slaughter of trillions of animals each year. These impacts are motivating calls for reduced reliance on animal-based products and increased use of replacement plant-based products. However, our understanding of how the production and consumption of animal products, as well as plant-based alternatives, interact with important dimensions of human and environment systems is incomplete across space and time. This inhibits comprehensively envisioning global and regional food system transitions and planning to manage the costs and synergies thereof. We therefore propose a cross-disciplinary research agenda on future target-based scenarios for food system transformation that has at its core three main activities: (1) data collection and analysis at the intersection of animal agriculture, the environment, and societal well-being, (2) the construction of target-based scenarios for animal products informed by these new data and empirical understandings, and (3) the evaluation of impacts, unintended consequences, co-benefits, and trade-offs of these target-based scenarios to help inform decision-making. [ABSTRACT FROM AUTHOR]

To feed the world population while mitigating pressing nitrogen (N) pollution problems, tremendous efforts have been devoted to developing and implementing N‐efficient technologies in crop or livestock production, but limited progress has been made. The N management improvement on a farm does not necessarily translate to N pollution reduction on a broader scale due to complex responses of natural and human systems and lack of coordination among stakeholders. Consequently, it is imperative to develop an N management framework that encompasses the complex N dynamics across systems and spatial scales, yet simple enough to guide policies and actions of various stakeholders. Here, we propose a new framework, CAFE, that defines four N management systems (Cropping, Animal‐crop, Food, and Ecosystem) in a hierarchical manner, and apply it to 13 representative countries to partition N surpluses across systems in a simple and consistent manner, thereby facilitating the identification and prioritization of systems‐based intervention strategies. Surprisingly, the Cropping system contributes less than half of the total N surplus within its Ecosystem for most countries, highlighting the importance of N management beyond croplands. This framework reveals that the relevant priorities and key stakeholders for enhanced N management vary among countries, such as improving the Cropping‐system efficiencies in China, adjusting the animal‐crop portfolio in the Netherlands, reducing food wastage in the U.S., and lowering crop storage losses and increasing overall production capacities in African countries. As N surplus increases along the CAFE hierarchy, systems‐based intervention strategies are revealed: (a) coupling chemical fertilizers with other N sources by maintaining half of the N from manure and biological N fixation; (b) coupling animal‐crop production by reducing animal density to lower than 1.2 livestock units per hectare, and increasing self‐sufficiency of animal feed to above 50%; (c) coupling food trade with domestic demand and production; and (d) coupling population needs for economic opportunities with environmental capacity of the region. This novel framework can help unpack the "wicked" N management challenges across systems to provide new insights and tools for improving N management on and beyond farms. Plain Language Summary: To tackle the "wicked" nitrogen (N) challenge, N‐efficient technologies in crop or livestock production alone are insufficient. A broader understanding of the complex dynamics and interactions across different N cycle systems and among various stakeholders is needed. We propose a new framework, CAFE, that defines four N management systems (Cropping system, Animal‐crop system, Food system, and landscape Ecosystem) in a hierarchical manner, and the quantitative relations represented by N surplus changes between adjacent CAFE systems are illustrated. Potential driving factors for N surplus increases across the CAFE systems are also identified, such as animal and population density, feed and food self‐sufficiency, etc. This framework can be used to partition N surpluses across systems and spatial scales in a simple and consistent manner, thereby facilitating the identification and prioritization of systems‐based intervention strategies. Applying CAFE to 13 representative countries reveals that the cropping system contributes to less than half of the total N surplus of its respective ecosystem for most countries, highlighting the importance of N management beyond croplands, and the relevant priorities and key stakeholders for enhanced N management vary among countries. Potential systems‐based intervention strategies are proposed with new insights for achieving sustainable N management. Key Points: Cropping, Animal‐crop, Food, and Ecosystem framework encompasses the complex N dynamics across systems and spatial scales to guide policiesPriorities and key stakeholders for enhanced N management vary among countriesSystematic solutions that improve the coupling of different system components were revealed [ABSTRACT FROM AUTHOR]

Since the 1980s, the widespread use of N fertilizer has not only resulted in a strong increase in agricultural productivity but also caused a number of environmental problems, induced by excess reactive N emissions. A range of approaches to improve N management for increased agricultural production together with reduced environmental impacts has been proposed. The 4R principles (right product, right amount, right time and right place) for N fertilizer application have been essential for improving crop productivity and N use efficiency while reducing N losses. For example, site-specific N management (as part of 4R practice) reduced N fertilizer use by 32% and increased yield by 5% in China. However, it has not been enough to overcome the challenge of producing more food with reduced impact on the environment and health. This paper proposes a new framework of food-chainnitrogen-management (FCNM). This involves good N management including the recycling of organic manures, optimized crop and animal production and improved human diets, with the aim of maximizing resource use efficiency and minimizing environmental emissions. FCNM could meet future challenges for food demand, resource sustainability and environmental safety, key issues for green agricultural transformation in China and other countries. [ABSTRACT FROM AUTHOR]

Multiple strategies are available that could reduce nitrogen (N) fertilizer use in agricultural systems, ranging from voluntary adoption of new N management practices by farmers to government regulations. However, these strategies have different economic and political costs, and their relative effectiveness in decreasing N leaching has not been evaluated at scale, particularly concerning potential trade-offs in crop yield and profitability. To inform policy efforts in the US Midwest, we quantified the effects of four policy scenarios designed to reduce fertilizer N inputs without sacrificing maize yields below 95%. A simulated dataset for economically optimum N rates and corresponding leaching losses was developed using a process-based crop model across 4,030 fields over 30 years. Policy scenarios were (1) higher N prices, (2) N leaching fee, (3) N balance fee, and (4) voluntary reduction of N use by farmers, each implemented under a range of sub-levels (low to high severity). Aggregated results show that all policies decreased N rates and N leaching, but this was associated with an exponential increase in economic costs. Achieving an N leaching reduction target of 20% has an estimated pollution control cost of 30–37 US$/ha, representing 147 million US$/year when scaled up to the state level, which is in the range of current government payments for existing conservation programs. Notably, such control of N losses would reduce the environmental impact of agriculture on water quality (externalities) by an estimated 524 million US$/year, representing an increase in society welfare of 377 million US$/year. Among the four policies, directly charging a fee on N leaching helped mitigate economic losses while improving the point source reduction effect (i.e., targeting fields that were leaching hotspots) and better internalization effect (i.e., targeting fields with higher environmental impact costs). This study provides actionable data to inform the development of cost-effective N fertilizer regulations by integrating changes in crop productivity and N losses in economic terms at the field level. [ABSTRACT FROM AUTHOR]

Deep learning has sparked a renaissance in computer systems and architecture. Despite the breakneck pace of innovation, there is a crucial issue concerning the research and industry communities at large: how to enable neutral and useful performance assessment for machine learning (ML) software frameworks, ML hardware accelerators, and ML systems comprising both the software stack and the hardware. The ML field needs systematic methods for evaluating performance that represents real-world use cases and useful for making comparisons across different software and hardware implementations. MLPerf answers the call. MLPerf is an ML benchmark standard driven by academia and industry (70+ organizations). Built out of the expertise of multiple organizations, MLPerf establishes a standard benchmark suite with proper metrics and benchmarking methodologies to level the playing field for ML system performance measurement of different ML inference hardware, software, and services. [ABSTRACT FROM AUTHOR]

Individuals with Spina Bifida (SB) have unique lifelong medical and social needs. Thus, when considering how to promote health and offer preventive care, providers must adapt general healthcare screening and counseling recommendations to their patients' physical and cognitive impairments along with discerning how to monitor secondary or chronic conditions common to the population. This article provides an update on the health promotion and preventive health care guidelines developed as part of the Spina Bifida Association's fourth edition of the Guidelines for the Care of People with Spina Bifida. The guidelines highlight accommodations needed to promote general preventive health, common secondary/chronic conditions such as obesity, metabolic syndrome, hypertension, musculoskeletal pain, and considerations for preventing acute care utilization for the SB population throughout the lifespan. Further research is needed to understand the effectiveness of preventive care interventions in promoting positive health outcomes and mitigating potentially preventable acute care utilization. [ABSTRACT FROM AUTHOR]

The influence of red blood cell (RBC) deformability in whole blood on platelet margination is investigated using confocal microscopy measurements of flowing human blood and cell resolved blood flow simulations. Fluorescent platelet concentrations at the wall of a glass chamber are measured using confocal microscopy with flowing human blood containing varying healthy-to-stiff RBC fractions. A decrease is observed in the fluorescent platelet signal at the wall due to the increase of stiffened RBCs in flow, suggesting a decrease of platelet margination due to an increased fraction of stiffened RBCs present in the flow. In order to resolve the influence of stiffened RBCs on platelet concentration at the channel wall, cell-pair and bulk flow simulations are performed. For homogeneous collisions between RBC pairs, a decrease in final displacement after a collision with increasing membrane stiffness is observed. In heterogeneous collisions between healthy and stiff RBC pairs, it is found that the stiffened RBC is displaced most. The influence of RBC deformability on collisions between RBCs and platelets was found to be negligible due to their size and mass difference. For a straight vessel geometry with varying healthy-to-stiff RBC ratios, a decrease was observed in the red blood cell-free layer and platelet margination due to an increase in stiffened RBCs present in flow. Author summary: The primary function of the human red blood cell is to deliver oxygen to the tissues of the body. The ability of the red blood cell to deform allows it to squeeze through small capillaries along with helping transport platelets to damaged areas on the vessel wall, which initiates normal coagulation function. Many diseases are known to impede the deformability of the red blood cell, which may adversely impact the transport of red blood cells and platelets in flow. We observe that with increasing fractions of stiff red blood cells in flow, there is a decrease of platelet margination. Specifically, this is observed as a decrease of the fluorescent platelet signal at the wall of a glass channel with flowing whole blood. We confirm this margination decrease by performing cell resolved simulations that reproduce the experiments. We also observe, in simulation, a decrease in the red blood cell-free layer as red blood cell deformability decreases. The decrease in the cell-free layer, we believe, is the most significant contributing factor to decreased margination. [ABSTRACT FROM AUTHOR]

In this article, we describe the design choices behind MLPerf, a machine learning performance benchmark that has become an industry standard. The first two rounds of the MLPerf Training benchmark helped drive improvements to software-stack performance and scalability, showing a 1.3× speedup in the top 16-chip results despite higher quality targets and a 5.5× increase in system scale. The first round of MLPerf Inference received over 500 benchmark results from 14 different organizations, showing growing adoption. [ABSTRACT FROM AUTHOR]

The radial distribution of cells in blood flow inside vessels is highly non-homogeneous. This leads to numerous important properties of blood, yet the mechanisms shaping these distributions are not fully understood. The motion of cells is governed by a variety of hydrodynamic interactions and cell-deformation mechanics. Properties, such as the effective cell diffusivity, are therefore difficult to investigate in flows other than pure shear flows. In this work, several single-cell, cell-pair, and large-scale many-cell simulations are performed using a validated numerical model. Apart from the single-cell mechanical validations, the arising flow profile, cell free layer widths, and cell drift velocities are compared to previous experimental findings. The motion of the cells at various radial positions and under different flow conditions is extracted, and evaluated through a statistical approach. An extended diffusive flux-type model is introduced which describes the cell diffusivities under a wide range of flow conditions and incorporates the effects of cell deformability through a shear dependent description of the cell collision cross sections. This model is applicable for both red blood cells and platelets. Further evaluation of particle trajectories shows that the margination of platelets cannot be the net result of gradients in diffusivity. However, the margination mechanism is strongly linked to the gradient of the hematocrit level. Finally, it shows that platelets marginate only until the edge of the red blood cell distribution and they do not fill the cell free layer. [ABSTRACT FROM AUTHOR]

The current national commitments under the Paris Climate Agreement fall short of what is needed to stay below a 2 °C increase in global average temperature. One approach that has been proposed to close this ambition gap is the building blocks strategy, which aims to encourage initiatives focused on non-climate actions that can deliver a climate benefit. A key option under this framework is reducing global nitrogen pollution. Nitrogen pollution—driven largely by the inefficient use of synthetic fertilizer and manure—is one of the most important environmental issues of the twenty-first century, not least because of its climate impacts. Ambitiously mitigating nitrogen pollution could avoid greenhouse gas emissions equivalent to 5–10% of the remaining allowable emissions consistent with the 2 °C target. However, the climate benefits would be a minor component of the overall environmental benefits of reducing nitrogen pollution, which would come mainly from avoided water and air pollution. The fact that these benefits would accrue mostly at local scales is especially important for countries like the United States, marked by a shift toward “economic nationalism.” In these countries, the most politically viable climate actions will likely be ones that produce local benefits as great, if not greater, than those achieved internationally. This is also likely to be true in countries like China, where local nitrogen-related issues such as air and water pollution remain major national priorities. Nevertheless, there are several challenges that could stand in the way of improved nitrogen management being a successful building block: integrated nitrogen management solutions that reduce the risk of pollution swapping need to be developed, the policy challenges related to changing and monitoring farmer behavior need to be addressed, and nitrogen’s role as an essential agricultural input needs to be respected. A better understanding of these challenges could also help policy-makers develop viable climate mitigation strategies across the entire agricultural sector. [ABSTRACT FROM AUTHOR]

Background: Reduced calorie, low fat diet is currently recommended diet for overweight and obese adults. Prior data suggest that low carbohydrate diets may also be a viable option for those who are overweight and obese. Purpose: Compare the effects of low carbohydrate versus low fats diet on weight and atherosclerotic cardiovascular disease risk in overweight and obese patients. Data Sources: Systematic literature review via PubMed (1966–2014). Study Selection: Randomized controlled trials with ≥8 weeks follow up, comparing low carbohydrate (≤120gm carbohydrates/day) and low fat diet (≤30% energy from fat/day). Data Extraction: Data were extracted and prepared for analysis using double data entry. Prior to identification of candidate publications, the outcomes of change in weight and metabolic factors were selected as defined by Cochrane Collaboration. Assessment of the effects of diets on predicted risk of atherosclerotic cardiovascular disease risk was added during the data collection phase. Data Synthesis: 1797 patients were included from 17 trials with <1 year follow up in 12. Compared with low fat diet, low carbohydrate was associated with significantly greater reduction in weight (Δ = -2.0 kg, 95% CI: -3.1, -0.9) and significantly lower predicted risk of atherosclerotic cardiovascular disease events (p<0.03). Frequentist and Bayesian results were concordant. The probability of greater weight loss associated with low carbohydrate was >99% while the reduction in predicted risk favoring low carbohydrate was >98%. Limitations: Lack of patient-level data and heterogeneity in dropout rates and outcomes reported. Conclusions: This trial-level meta-analysis of randomized controlled trials comparing LoCHO diets with LoFAT diets in strictly adherent populations demonstrates that each diet was associated with significant weight loss and reduction in predicted risk of ASCVD events. However, LoCHO diet was associated with modest but significantly greater improvements in weight loss and predicted ASCVD risk in studies from 8 weeks to 24 months in duration. These results suggest that future evaluations of dietary guidelines should consider low carbohydrate diets as effective and safe intervention for weight management in the overweight and obese, although long-term effects require further investigation. [ABSTRACT FROM AUTHOR]

Agriculture in the United States (US) cycles large quantities of nitrogen (N) to produce food, fuel, and fiber and is a major source of excess reactive nitrogen (Nr) in the environment. Nitrogen lost from cropping systems and animal operations moves to waterways, groundwater, and the atmosphere. Changes in climate and climate variability may further affect the ability of agricultural systems to conserve N. The N that escapes affects climate directly through the emissions of nitrous oxide (NO), and indirectly through the loss of nitrate (NO), nitrogen oxides (NO) and ammonia to downstream and downwind ecosystems that then emit some of the N received as NO and NO. Emissions of NO lead to the formation of tropospheric ozone, a greenhouse gas that can also harm crops directly. There are many opportunities to mitigate the impact of agricultural N on climate and the impact of climate on agricultural N. Some are available today; many need further research; and all await effective incentives to become adopted. Research needs can be grouped into four major categories: (1) an improved understanding of agricultural N cycle responses to changing climate; (2) a systems-level understanding of important crop and animal systems sufficient to identify key interactions and feedbacks; (3) the further development and testing of quantitative models capable of predicting N-climate interactions with confidence across a wide variety of crop-soil-climate combinations; and (4) socioecological research to better understand the incentives necessary to achieve meaningful deployment of realistic solutions. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) is the largest known remaining anthropogenic threat to the stratospheric ozone layer. However, it is currently only regulated under the 1997 Kyoto Protocol because of its simultaneous ability to warm the climate. The threat N2O poses to the stratospheric ozone layer, coupled with the uncertain future of the international climate regime, motivates our exploration of issues that could be relevant to the Parties to the ozone regime (the 1985 Vienna Convention and its 1987 Montreal Protocol) should they decide to take measures to manage N2O in the future. There are clear legal avenues to regulate N2O under the ozone regime as well as several ways to share authority with the existing and future international climate treaties. N2O mitigation strategies exist to address the most significant anthropogenic sources, including agriculture, where behavioral practices and new technologies could contribute significantly to reducing emissions. Existing policies managing N2O and other forms of reactive nitrogen could be harnessed and built on by the ozone regime to implement N2O controls. There are several challenges and potential cobenefits to N2O control which we discuss here: food security, equity, and implications of the nitrogen cascade. The possible inclusion of N2O in the ozone regime need not be viewed as a sign of failure of the United Nations Framework Convention on Climate Change to adequately deal with climate change. Rather, it could represent an additional valuable tool in sustainable development diplomacy. [ABSTRACT FROM AUTHOR]

Project-based science (PBS) curricula have project- and inquiry-based aspects that leverage the strengths of urban students from ethnic and racial groups underrepresented in science careers, potentially impacting positively these students' science achievement and attitudes and thus their college and career plans. We aimed to determine the extent to which a PBS curriculum would show this. We provided professional development to bolster urban teachers' science content knowledge (CK) and science pedagogical content knowledge (PCK) to observe the maximal impact of the PBS curriculum. We found that students' science achievement improved with the PBS curriculum, but that their attitudes toward science and plans to pursue science did not. Increases in teachers' CK and PCK with the professional development correlated with the improvements in student science achievement but did not correlate with improvements in student science attitudes or plans. However, the frequency of teachers' use of specific inquiry-based activities did correlate with improvements in students' science attitudes and plans. In sum, the extent of the success of a PBS curriculum with students from groups underrepresented in science careers appears to be dependent on elements of both teacher knowledge (CK and PCK) and teachers' frequency of use of inquiry-based activities that are consistent with culturally relevant pedagogical practices. © 2010 Wiley Periodicals, Inc. Sci Ed94:855–887, 2010 [ABSTRACT FROM AUTHOR]

Project-based science curricula can improve students' usable or meaningful understanding of the science content underlying a project. However, such curricula designed around “performances” wherein students design or make something do not always do this. We researched ways to design performance project-based science curricula (pPBSc) to better support the meaningful understanding of science content. Using existing curriculum design frameworks, we identified the learner's need to “create the demand” for the science content, anticipating how to use it in the performance, and to “apply” the science content, both being necessary to ensure meaningful understanding. Designing the pPBSc I, Bio we discovered how these guiding principles manifested as curriculum design challenges. We generalized from the design of I, Bio and related literature design approaches for addressing each challenge. Finally, we measured the extent to which a pPBSc incorporating these design approaches developed meaningful understanding. 652 middle grades students using I, Bio completed pre- and posttests on the science content behind the I, Bio performance. Our findings provide preliminary evidence that a pPBSc that incorporates these design approaches is consistent with gains in meaningful understanding. We discuss how the results of this work can be used to improve systematic experiments on instructional supports. © 2009 Wiley Periodicals, Inc. Sci Ed94:525–551, 2010 [ABSTRACT FROM AUTHOR]

This chapter explores the extent to which project-based science (PBS) curricula designed with supports for students' inquiry into complex scientific data can help urban students make sense of such data and promote their deep understanding of standards-based content. We review qualitative and quantitative data from classroom enactments of a PBS high school biology curriculum called Disease Detectives. [ABSTRACT FROM AUTHOR]

The 1989 Cable Act eliminated most price regulation of cable television operators, including the right of municipalities to enforce price terms in franchise agreements. Deregulation was justified, at least partially, by the contention that competition from other entertainment media eliminated any market power of cable franchises. We examine the value at sale of existing cable systems before and after deregulation. Assuming that this value represents the expected present value of future profits, deregulation had the predicted negligible effect on profits in cities with significant broadcast competition. However, profits appear to have increased in areas where the competition from broadcast television was less severe. We explore several explanations for this increase and conclude that significant market power is the most plausible explanation. [ABSTRACT FROM AUTHOR]

Poster 286 Relapsing Remitting Polyradiculoneuropathy Associated With Graft-Versus-Host Disease After Peripheral Blood Stem Cell Transplant for Acute Myelogenous Leukemia: A Case Report Patients or Programs A 55-year-old man presented with weakness and numbness 9 months after unrelated, matched, peripheral blood stem cell transplantation for treatment of acute myelogenous leukemia. Peripheral neuropathies after stem cell transplantation are uncommon, however, a small subset of patients can develop IDPs; little is known regarding the length of treatment and long-term outcomes. [Extracted from the article]