Top PDF Evolution of soybean weed management in the United States

Evolution of soybean weed management in the United States

Evolution of soybean weed management in the United States

experienced. The heavy selection pressure during the 1980’s resulted in a high number of weed populations with resistance to ALS-inhibitor chemistry. The introduction of glyphosate-tolerant soybeans offered soybean producers an answer to this issue. Glyphosate applied to glyphosate-tolerant soybeans easily controlled all weeds that were present in soybean fields. This simplified weed management by giving farmers the option to control all weed issues with the application of one herbicide. A rapid adoption of this technology quickly followed and nearly all weed management was approached with this one dimensional tool for the during the years following the technology release (Young, 2006). Overreliance of glyphosate alone has proved to be a selection pressure that has yielded weed populations with resistance to glyphosate. Weed species with resistance to herbicides continues to grow and the number of sites of action with resistant weed populations continues to grow (Heap, 2014). The list of new herbicides with new sites of action available for commercial use has stopped growing. This leaves growers without new novel herbicides to battle weed populations that are increasingly less likely to be controlled with the herbicides of the past. The answer by the seed industry has been an increase in genetically-modified crops with resistance to a broader range of herbicides that have been in use for many years.
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On the evolution of income inequality in the United States

On the evolution of income inequality in the United States

7. INEQUALITY TRENDS BEFORE THE 1960 S In this section, we summarize findings of studies of the evolution of income inequality in the United States before the 1960s. There are no large-scale regular population surveys that include individual labor income data during this period. Before 1940, even the decennial U.S. Census did not ask about income (see Williamson and Lindert 1980 and Margo 1999 for discussions of these data limitations). Thus, income inequality before 1940 can only be roughly estimated from sources such as irregular local surveys, state censuses, and tax returns.
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The Evolution of the Mexican-Born Workforce in the United States

The Evolution of the Mexican-Born Workforce in the United States

This paper examines the evolution of the Mexican-born workforce in the United States using data drawn from the decennial U.S. Census throughout the entire 20th century. It is well known that there has been a rapid rise in Mexican immigration to the United States in recent years. Interestingly, the share of Mexican immigrants in the U.S. workforce declined steadily beginning in the 1920s before beginning to rise in the 1960s. It was not until 1980 that the relative number of Mexican immigrants in the U.S. workforce was at the 1920 level. The paper examines the trends in the relative skills and economic performance of Mexican immigrants, and contrasts this evolution with that experienced by other immigrants arriving in the United States during the period. The paper also examines the costs and benefits of this influx by examining how the Mexican influx has altered economic opportunities in the most affected labor markets and by discussing how the relative prices of goods and services produced by Mexican immigrants may have changed over time.
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Modelling the Evolution of Credit Spreads in the United States

Modelling the Evolution of Credit Spreads in the United States

v Abstract The authors use Jarrow and Turnbull’s (1995) reduced-form methodology to model the evolution of the term structure of interest rates in the United States for different credit classes and different industries. The authors also estimate a liquidity function for each credit class and industry. Using data from individual firms, the authors estimate the probability of default under the natural measure and compare it with the estimated default frequencies produced by KMV.

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Evolution of the conceptual framework for business enterprises in the United States

Evolution of the conceptual framework for business enterprises in the United States

THE EVOLUTION OF THE CONCEPTUAL FRAMEWORK FOR BUSINESS ENTERPRISES IN THE UNITED STATES Abstract: Institutional efforts in the U.S. to develop a conceptual framework for business enterprises can be traced to the Paton and Littleton monograph in 1940 and later to the two Accounting Re- search Studies by Moonitz and Sprouse in 1962-1963. A committee of the American Accounting Association issued an influential report in which it advocated a “decision usefulness” approach in 1966, which was carried forward in 1973 by the report of the American Institute of CPAs’ Trueblood Committee. All of this laid the ground- work for the conceptual framework project of the Financial Ac- counting Standards Board (FASB), which published six concepts statements between 1978 and 1985. A seventh concepts statement is likely to be published in 2000. It is still not clear how the FASB’s conceptual framework has influenced the setting of accounting standards, and some academic commentators are skeptical of the usefulness of all normative conceptual framework projects.
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Evolution of the Pediatric Influenza Vaccination Program in the United States

Evolution of the Pediatric Influenza Vaccination Program in the United States

Evolution of the Pediatric In fl uenza Vaccination Program in the United States For many years, the Advisory Committee on Immunization Practices (ACIP) for the Centers for Disease Control and Prevention (CDC) focused its vaccination policy on persons at higher risk for in fl uenza compli- cations (eg, older adults, children and adults with certain high-risk conditions, pregnant women) and their contacts (eg, household con- tacts, health care personnel). Unfortunately, although vaccination coverage rates varied, they remained low for most adult and pediatric high-risk groups, other than persons aged $ 65 years. 1 In conjunction with the recognition that in fl uenza vaccination recommendations for high-risk target populations were not being optimally implemented, the adverse effects of in fl uenza illness on all children was increasingly recognized. This led to the expansion of vaccination recommendations for children, beginning in 2002, when in fl uenza vaccination was “ encouraged ” for children aged 6 through 23 months, and in 2004, when a full rec- ommendation was issued for this age group. 2,3 That recommendation was based largely on studies documenting that these young children had in fl uenza-related hospitalization rates that were comparable to hospitalization rates in older persons with underlying risk conditions who were targeted to receive in fl uenza vaccine. 4 – 6 Full recommendation was added for other groups who are at risk, such as adults and children with neuromuscular and other conditions that can compromise respiratory function or the handling of respiratory secretions, as data became available. 7
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Evolution of Longwall Mining and Control Systems in the United States

Evolution of Longwall Mining and Control Systems in the United States

Abstract - this paper addresses the evolution of longwall mining in the United States from the initial "longwall" method, utilizing hand loading and manual haulage to the progressive mechanization of the face equipment. An analysis of accident information for specific benchmark dates in United States longwall evolution and a review of productivity (for the period of 1963 - 1973) are provided to demonstrate the impact of longwall mining advancements in these areas. It also addresses how the previous generation of machines and methods influenced the next, up to the present and addresses the introduction and advancements of automated control systems and the Mine Safety and Health Administration’s safety concerns associated with them. Among the systems to be discussed are microprocessor controlled shearers and roof supports.
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Muslims and evolution: a study of Pakistani physicians in the United States

Muslims and evolution: a study of Pakistani physicians in the United States

Abstract This study investigated the views of Pakistani-American medical doctors regarding biological evolution. We used a mixed-methods approach, chiefly consisting of a short interview that presented evolution in the contexts of microbial, animal, and human evolution; evolution's acceptability or unacceptability to Muslims; and evolution's relevance to medicine. The participants were 23 doctors attending a convention in the United States. Fourteen participants accepted evolution, three rejected evolution, and six held other views. While a majority of participants indicated that they accepted evolution, a slightly smaller plurality accepted human evolution. A majority of participants, including some who did not wholly accept or reject evolution, thought that one could mutually accept evolution and also believe in Allah. Nearly every participant, including two who rejected evolution, thought that evolution was relevant to medicine. We find that participants assigned a plurality of meanings to the theory that depended on interactions between a participant ’ s perception of religion, science, medicine, and a host of other cultural influences. This study is the first of a collection of studies carried out by the authors, who collected data with the same instrument in five other countries with significant populations of Muslim doctors and medical students.
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The Evolution of Trial Practice in the United States Tax Court

The Evolution of Trial Practice in the United States Tax Court

I foolishly agreed to write an article on the evolution of trial practice in the United States Tax Court (hereinafter Tax Court or Court) on the occasion of the Tax Section’s 75th anniversary before I considered what it should include. So much has changed about the Court since I first started to practice before it in 1974 that it is hard to identify the most significant changes, and even then, my decision to write about some changes and not others is necessarily subjective, depending as it is on my own experience as a tax controversy and trial lawyer for 24 years and then as a Tax Court judge for over 16 years. But, having made the commitment to write this Article, I have chosen to write about developments affecting the Court’s jurisdiction, rules, processes, and operating procedures that I think are particularly important to the evolution of the Court.
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Evolution of soybean weed management in the United States

Evolution of soybean weed management in the United States

experienced. The heavy selection pressure during the 1980’s resulted in a high number of weed populations with resistance to ALS-inhibitor chemistry. The introduction of glyphosate-tolerant soybeans offered soybean producers an answer to this issue. Glyphosate applied to glyphosate-tolerant soybeans easily controlled all weeds that were present in soybean fields. This simplified weed management by giving farmers the option to control all weed issues with the application of one herbicide. A rapid adoption of this technology quickly followed and nearly all weed management was approached with this one dimensional tool for the during the years following the technology release (Young, 2006). Overreliance of glyphosate alone has proved to be a selection pressure that has yielded weed populations with resistance to glyphosate. Weed species with resistance to herbicides continues to grow and the number of sites of action with resistant weed populations continues to grow (Heap, 2014). The list of new herbicides with new sites of action available for commercial use has stopped growing. This leaves growers without new novel herbicides to battle weed populations that are increasingly less likely to be controlled with the herbicides of the past. The answer by the seed industry has been an increase in genetically-modified crops with resistance to a broader range of herbicides that have been in use for many years.
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Evolution of cool-roof standards in the United States

Evolution of cool-roof standards in the United States

In January 2001, the state of California followed the ASHRAE approach by crediting in its “Title 24” Building Energy Efficiency Standards for Residential and Nonresidential Buildings the use of cool roofing products on nonresidential buildings with low-sloped roofs (CEC 2001). In 2005, California upgraded Title 24 to prescribe minimum values of solar reflectance and thermal emittance for low-sloped roofs (i.e., roofs with a ratio of rise to run not exceeding 2:12) on nonresidential buildings (CEC 2006). As of June 2007, California is evaluating proposals to prescribe in the 2008 Title 24 standards minimum values of solar reflectance and thermal emittance for low-sloped roofs on nonresidential buildings, and for both low-sloped and steep- sloped roofs on residential buildings. Other states and cities, including Florida and Chicago, IL, have adopted custom cool-roof requirements in their energy codes.
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The variables related to public acceptance of evolution in the United States

The variables related to public acceptance of evolution in the United States

biological evolution is related to, and especially impor- tant to, medical advances and understanding diseases. Disease-causing bacteria and viruses can evolve into strains that are resistant to medication. It is imperative that patients, clinicians, and pharmacologists understand the potential evolutionary pathways for disease-causing microbes and the implications for treatments and phar- maceutical development. Finally, acceptance of evolution is important for scientists who test on animals. Cer- tain animals are more genetically close to humans than others and, therefore, make better subjects for testing drugs, cosmetics, toxins, and other potentially harmful or beneficial substances. Knowledge of the distinct pro- ximal and distal animal-human relationships can lead to the optimization of animal research to human benefit.
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Evolution of Swine H3N2 Influenza Viruses in the United States

Evolution of Swine H3N2 Influenza Viruses in the United States

swine H1N1 viruses may help determine the evolutionary steps that led to the emergence of these viruses. The establishment of the triple-reassortant virus in the United States has implications for both swine and human health. The transmission of H1N1 and H3N2 swine influenza viruses to humans has been documented (9, 11, 23, 26, 34, 37, 38). Although some of these interspecies transmissions have resulted in human fatalities, there has been limited human-to- human spread and no stable lineages have been established. As the distribution of the triple-reassortant virus increases, the contact between infected pigs and humans will increase corre- spondingly. The swine H3N2 viruses are antigenically similar to recent human viruses and therefore pose little direct threat to the human population. However, the potential exists for the transfer of the avian-like PA and PB2 genes to human viruses.
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Origin, Evolution, and Virulence of Porcine Deltacoronaviruses in the United States

Origin, Evolution, and Virulence of Porcine Deltacoronaviruses in the United States

IMPORTANCE Porcine coronaviruses (CoVs) are major viral infectious diseases of swine. Examples of porcine CoVs include por- cine transmissible gastroenteritis coronavirus (TGEV), porcine epidemic diarrhea virus (PEDV), and porcine respiratory coro- navirus (PRCV). In February 2014, another porcine CoV, porcine deltacoronavirus (PdCV), emerged in Ohio and Indiana and subsequently spread rapidly across the United States and Canada, causing significant economic losses. Here, we report the de- tailed genetic characterization, phylogeny, and virulence of emergent PdCV strains in the United States. We found that PdCV caused severe diarrhea, vomiting, and dehydration in gnotobiotic and conventional piglets, signs that were clinically indistin- guishable from those caused by PEDV and TGEV. In addition to extensive intestinal lesions, PdCV caused significant lesions in the stomach and mild pulmonary lesions that have not been reported for TGEV and PEDV. The finding that PdCV is a signifi- cant enteric disease of swine highlights the need to develop effective measures to control this disease.
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Sociology of Professions: The Evolution of Landscape Architecture in the United States

Sociology of Professions: The Evolution of Landscape Architecture in the United States

Based on these theoretical standards, the findings of this study include possible reasons for landscape architecture's slower evolution in public recognition and acceptance, as well[r]

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The Evolution of Public Sector Pension Plans in the United States

The Evolution of Public Sector Pension Plans in the United States

latest information on the websites of the various state employee retirement plans to supplement the 2006 Wisconsin data. Table 14-A1 presents information from state retirement plans in 1982 on the normal retirement age specified in the plan, the number of years used to determine the final salary average, and the retirement multipliers in the benefit formula. These values are then contrasted with the data for 2006 to show how state employee retirement plans have evolved over the past 25 years. In general, the states have substantially increased the generosity of their pension plans over the years. Thirty-three states modified the normal retirement ages specified in the plans that allowed workers to retire at ear- lier ages with fewer years of service; while six states increased their normal retirement ages (NRA) somewhat, including Minnesota, which linked the NRA for state retirement benefits to the NRA for Social Security. Fifteen states reduced the number of years in the averaging period, thus raising final pension benefits; while only Alaska increased the number of years in its averaging period. Finally, 30 states increased the multipliers and/or eliminated Social Security offsets, and four states reduced the multipliers used to calculate retirement benefits. As a result of these changes, holding other factors constant, the typical state employee will retire with a higher replacement ratio in 2006 than in 1982.
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Valuing the Roundup Ready® Soybean Weed Management Program

Valuing the Roundup Ready® Soybean Weed Management Program

Herbicide tolerant and insect resistant crop varieties like Roundup Ready® (RR) soybean and Bt corn have now been in use for over a decade in the U.S. In 2008, the United States Department of Agriculture’s National Agricultural Statistics Service reported that 80 percent of corn, 86 percent of cotton, and 92 percent of soybean acreage in the U.S. was planted with either herbicide tolerant, insect resistant, or a combination of herbicide tolerant and insect resistant varieties. Such rapid adoption of a new technology suggests that growers perceive significant benefits. Marra et al.’s (2002) review of the literature generally supports this hypothesis, though there are a few cases where benefit estimates do not always appear to favor the new varieties over their conventional counterparts (see for example Duffy and Ernst, 1999; and Fernandez- Cornejo and McBride, 2002). Even though the weight of evidence suggests the new varieties currently provide substantial benefits to growers, critics contend that these benefits may be short- lived because adoption can lead to unsustainable production practices (e.g. Benbrook, 2001). Therefore, it seems prudent to regularly monitor the benefits provided by these new crop varieties and to explore how the adoption of production practices to promote sustainability may enhance these benefits.
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Management Recommendations for Soybean Aphid (Hemiptera: Aphididae) in the United States

Management Recommendations for Soybean Aphid (Hemiptera: Aphididae) in the United States

2008, Knodel et al. 2009, Magalhaes et al. 2009). Use of seed treatments is more of an insurance policy than an IPM strategy to protect against early season soybean aphid infestations. It is difficult to predict if soybean aphid will reach economic levels early in the season when seed treatments are most effective. A predictive forecasting system for soybean aphid would be helpful for growers to make decisions on whether to use a seed treatment the next year. Research has demon- Fig. 6. Common soybean aphid look-alikes, including a) minute pirate bug, Orius tristicolor, nymph. Photo credit to Bradley Higbee; b) potato leafhopper, Empoasca fabae, nymph. Photo credit to Marlin E. Rice.; c) silverleaf whitefly, Bemisia tabaci. Photo credit to Stephen Ausmus; d) trochanter mealybug, Pseudococcus sorghiellus. Photo credit to Ronald Hammond; e) soybean thrips, Sericothrips variabilis.
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Dynamics of Early-Season Weed Management and Soybean Nutrition

Dynamics of Early-Season Weed Management and Soybean Nutrition

CHAPTER 4 CONCLUSIONS The evolution of herbicide-resistant weeds has resulted in a dramatic reassessment of weed management strategies in soybean. The efficacy provided by postemergent (POST) herbicides such as glyphosate is often no longer satisfactory to meet grower demands in areas plagued by these troublesome weed biotypes that may also have resistance to multiple other herbicide sites of action. The challenge of herbicide-resistant weeds in soybean production has led to a resurgent use of soil residual herbicides and other early-season weed management tactics to combat their spread. In regions that remain unaffected by glyphosate-resistant weeds, POST herbicides are still an effective and viable option for weed control; however, prior knowledge would suggest that such a great reliance on POST-only control measures are precisely the cause for the fruition of herbicide-resistant weeds. Furthermore, the flexibility provided by POST strategies would make it appear to be the most parsimonious choice, yet this can often result in a complacent understanding of what constitutes a timely herbicide application in order to avoid crop yield losses from prolonged weed competition. To facilitate the implementation of more sound weed and herbicide-resistant management tactics, an evaluation of additional benefits provided by early-season weed management in soybean was performed in this research.
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Management of Insecticide-Resistant Soybean Aphids in the Upper Midwest of the United States

Management of Insecticide-Resistant Soybean Aphids in the Upper Midwest of the United States

of insecticide could include the various labeled products (Table 1, Fig. 3). If pyrethroid-resistance is suspected in an aphid population, products containing insecticides other than pyrethroids should be considered. Pyrethroid-containing mixtures may provide adequate control of some pyrethroid-resistant populations of soybean aphid (IRAC 2012, R.L.K. and B.D.P., unpublished data). However, pyre- throid-containing mixtures should generally be avoided for use against pyrethroid-resistant populations (IRAC 2012) (Fig. 3). In such situations, the pyrethroid component of such products may be compromised by the resistance. In addition, the amount of each active ingredient in some mixtures is less than that of products with single active ingredients. Furthermore, depending on factors such as relative efficacy, durations of residual activity, and levels of cross resistance, use of some mixtures could provide additional selection pressure for further development of insecticide resistance (IRAC 2012). When selecting insecticides, keep in mind that the ‘the pri- mary intention for the use of an insecticide mixture (tank-mix or pre-formulated mixture) is, in most cases, not resistance manage- ment but pest management’ (IRAC 2012). It should also be noted that soybean fields planted with neonicotinoid-treated seeds have already received an application of a Group 4 insecticide (i.e., neon- icotinoids). Populations of clonally reproducing aphids in such fields may have already been exposed to this systemic, seed-applied insec- ticide. Therefore, we caution against the use of neonicotinoid-con- taining insecticides for a first foliar application to such fields (Fig. 3). Finally, if soybean is in bloom, consider insecticide options with reduced risk to pollinators (Zhu et al. 2015).
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