Market Penetration of Biomass Fuels for Electricity Generation

The electric power sector is a main source of carbon dioxide (CO2) emissions that contribute to global warming. In the U.S., fossil fuel fired power plants are responsible for about 38% of the total CO2 emissions from all sources. Switching a significant portion of the U.S. electricity generating capacity from fossil fuels to biomass fuels would help reduce CO2 emissions from the electric power industries. At present, biomass accounts for only about 1% of the fuel used for electricity generation in the U.S. In contrast, coal alone accounts for about 50%, and nuclear, natural gas and petroleum explain for about 20%, 16% and 3% respectively of the fuels used for electricity generation. There are a number of factors that may influence the extent to which biomass fuels are to penetrate the electricity market: facility needs, growth in electricity demand, prices of fossil fuels and advances in technology. Electricity is generally produced in large, expensive and long-lived facilities. However new facilities or capitals are often built to meet demand growth. Capitals can be generally said to have a given productive lifetime. As new capital investment occurs and older capital is retired, electricity producers will have opportunities to substitute away from fossil fuels. Thus, an increase in the market penetration of biomass power will likely occur when existing fossil power plants are retired and replaced by new and less carbon intensive power plants. The market penetration of biomass electricity will also depend on a strong growth in electricity demand due to economic and population growth, availability and prices of fuels, environmental considerations and technological advances. Specifically, this paper will look at the potential for biomass penetration into the electricity market considering: a) prices of fossil fuels such as coal, natural gas and petroleum for power production, b) the capital turnover rate for existing stock of fossil power plants, c) changes in technologies which could facilitate the use of biomass as fuels for electricity generation.Resource /Energy Economics and Policy,

Economics of Biomass Fuels for Electricity Production: A Case Study with Crop Residues

In the past, studies on agricultural feedstocks for energy production were motivated by rising fossil fuel prices interpreted by many as caused by resource depletion. However, today's studies are mainly motivated by concerns for climate change and global warming. Currently, most studies concentrate on liquid fuels with little study devoted toward electricity. This study examines crop residues for electricity production in the context of climate change and global warming. We use sector modeling to simulate future market penetration for biopower production from crop residues. Our findings suggest that crop residues cost much more than coal because they have lower heat content and higher production/hauling costs. For crop residues to have any role in electricity generation either the carbon or carbon dioxide equivalent greenhouse gas price must rise to about 15 dollars per ton or the price of coal has to increase to about 43 dollars per ton. We find crop residues with higher heat content and lower production costs such as wheat residues have greater opportunities in biopower production than the residues with lower heat content and higher production costs. In addition, the analysis shows that improvements in crop yield do not have much impact on biopower production. However, the energy recovery efficiency does have significant positive impact but only if the carbon equivalent price rises substantially. The analysis also indicates the desirability of cofiring biomass as opposed to 100% replacement because this reduces hauling costs and increases the efficiency of heat recovery. In terms of policy implications, imposing carbon emission pricing could be an important step in inducing electric power producers to include agricultural biomass in their fuel-mix power generation portfolios and achieve greenhouse gas emission reductions.Resource /Energy Economics and Policy,

The Viability of Harvesting Corn Cobs and Stover for Biofuel Production in North Dakota

This study examines the impact of stochastic harvest field time, corn cob and stover harvest technologies, increases in farm size, and alternative tillage practices on profit maximizing potential of corn cob and stover collection in North Dakota. Using three mathematical programming models, we analyze farmers’ harvest activities under 1) corn grain only harvest option, 2) simultaneous corn grain and cob harvest(one-pass) option 3) separate corn grain and stover harvest (two-pass) option. Under the first corn grain only option, farmers are able to complete harvesting corn grain and achieve maximum net income in a fairly short amount of time with existing combine technology. However, under the simultaneous corn grain and cob one-pass harvest option, our findings indicate that farmers generate lower net income as compared to the net income of corn grain only harvest option. This is due to the slowdown in combine harvest capacity as a consequence of attaching cob harvester to the back of combine. Under the third option of a two-pass harvest system, time allocation is the main challenge and our evidence shows that with limited harvest field time available, farmers find it optimal to allocate most of their time harvesting grain, and then proceed to bale stover if time permits at the end of harvest season. As farm size increases, farmers are especially challenged in finding time to harvest both corn grain and cobs/stover. We show that a small decrease in corn yield due to changes in tillage practice can result in a large decline in the net profit of harvesting corn grain and cobs/stover.Cob, Stover, harvest field time, optimization, farm size, tillage, Crop Production/Industries, Production Economics,

Economics of Sourcing Cellulosic Feedstock for Energy Production

This study investigates the economics of supplying wheat straw and corn stover within 100 mile radius of a potential new biorefinery in southeast North Dakota. In particular, straw and stover total delivery costs, potential straw and stover supply sites and least cost transportation routes are identified using a linear programming transport model and a GIS (Geographic Information Systems) mapping system. We show that USDA/NRCS (Natural Resources Conservation Service) future crop residue removal rate policies will be important for determining whether it is economically viable to harvest crop residues as potential feedstock for energy generation. Increase in residue removal rates narrow the size of residue supply areas and consequently result in lowering total transportation costs. There is an economic tradeoff between residue collection density and distance from the biorefinery. Most wheat residues are highly concentrated in the north, some distance from the biorefinery. Relying solely on wheat straw for supply needs require longer transportation distances which increases total cost. Using a combination of wheat and corn residues lowers total transportation costs. Since most wheat/corn residues are densely concentrated in north/south, regional highways would likely be the routes used often to transport the residues, as compared to interstate highways. Increased traffic volumes due to the hauling of crop residues would require additional investment in improving road conditions.Wheat Straw, Corn Stover, Density, Transportation Cost, GIS, Community/Rural/Urban Development, Crop Production/Industries,

Clinical importance of the Mandalay spitting cobra (Naja mandalayensis) in Upper Myanmar – Bites, envenoming and ophthalmia

This is an accepted manuscript of an article published by Elsevier in Toxicon on 03/06/2020, available online: https://doi.org/10.1016/j.toxicon.2020.05.023 The accepted version of the publication may differ from the final published version.© 2020 Elsevier Ltd Examination of 18 cobras brought to three hospitals in the Mandalay Region by patients bitten or spat at by them distinguished 3 monocled cobras (Naja kaouthia) and 15 Mandalay spitting cobras (N. mandalayensis), based on their morphological characteristics. We confirm and extend the known distributions and habitats of both N. mandalayensis and N. kaouthia in Upper Myanmar. Clinical symptoms of local and systemic envenoming by N. mandalayensis are described for the first time. These included local swelling, blistering and necrosis and life-threatening systemic neurotoxicity. More information is needed about the clinical phenotype and management of bites by N. mandalayensis, the commoner of the two cobras in Upper Myanmar. Since the current cobra antivenom manufactured in Myanmar has lower pre-clinical efficacy against N. mandalayensis than N. kaouthia, there is a need for more specific antivenom therapy.Published versio

Systemic mastocytosis associated with t(8;21)(q22;q22) acute myeloid leukemia

Although KIT mutations are present in 20–25% of cases of t(8;21)(q22;q22) acute myeloid leukemia (AML), concurrent development of systemic mastocytosis (SM) is exceedingly rare. We examined the clinicopathologic features of SM associated with t(8;21)(q22;q22) AML in ten patients (six from our institutions and four from published literature) with t(8;21) AML and SM. In the majority of these cases, a definitive diagnosis of SM was made after chemotherapy, when the mast cell infiltrates were prominent. Deletion 9q was an additional cytogenetic abnormality in four cases. Four of the ten patients failed to achieve remission after standard chemotherapy and seven of the ten patients have died of AML. In the two patients who achieved durable remission after allogeneic hematopoietic stem cell transplant, recipient-derived neoplastic bone marrow mast cells persisted despite leukemic remission. SM associated with t(8;21) AML carries a dismal prognosis; therefore, detection of concurrent SM at diagnosis of t(8;21) AML has important prognostic implications

Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: A pooled analysis of 1018 population-based measurement studies with 88.6 million participants

© The Author(s) 2018. Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probittransformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. Results: In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the highincome Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Conclusions: Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups

Repositioning of the global epicentre of non-optimal cholesterol

High blood cholesterol is typically considered a feature of wealthy western countries(1,2). However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world(3) and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health(4,5). However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol-which is a marker of cardiovascular riskchanged from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million-4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.Peer reviewe

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks