Future US Research Articles

Sunny with a Chance of Curtailment: Operating the US Grid with Very High Levels of Solar Photovoltaics.

SummaryWith rapid declines in solar photovoltaic (PV) and energy storage costs, futures with PV penetrations approaching or exceeding 50% of total annual US generation are becoming conceivable. The operational merits of such a national-scale system have not been evaluated sufficiently. Here, we analyze in detail the operational impacts of a future US power system with very high annual levels of PV (>50%) with storage. We show that load and operating reserve requirements can be met for all hours while considering key generator operational constraints. Storage plays an active role in maintaining the balance of supply and demand during sunset hours. Under the highest PV penetration scenario, hours with >90% PV penetration are relatively common, which require rapid transitions between predominately conventional synchronous generation and mostly inverter-based generation. We observe hours with almost 400 GW (over 40%) of economic curtailment and frequent (up to 36%) hours with very low energy prices.

Measuring Bond Investors’ Risk Appetite Using the Interest Rate Term Structure

The distribution of term premia includes additional information beyond that contained in the traditional three-parameter decomposition of the Treasury yield curve. The author finds that the position and the size of the curvature hump are both important. A yield curve hump positioned at longer maturities appears to be consistent with lengthier time horizons of investors and with more risk-seeking behavior. The author finds that this new parameter Granger drives both future US economic activity and bond returns. TOPICS:Fixed income and structured finance, fixed-income portfolio management, statistical methods

Japan’s Diplomatic Strategy toward East Asia: Creation and Evolution of ‘Dual-Track Diplomacy’ in the Post-Cold War Era

Abstract Japan’s diplomatic strategy toward East Asia underwent three main changes in the post-Cold War era. The first change occurred soon after the 1991 Persian Gulf War propelled Japan to consider a potential way to contribute to international security, resulting in the creation of dual-track diplomacy. The second was the consolidation of Japan’s dual-track diplomacy by strengthening the US–Japan alliance and supporting the ASEAN’s multilateral initiatives in the early 2000s. The third was the enhancement of Japan’s own security efforts to maintain regional stability while making the most of the existing political and security mechanisms in East Asia—multilateralizing US alliance networks and enhancing the ASEAN-led multilateral frameworks. In the future, two factors would likely play a critical role in shaping Japan’s diplomatic strategy: the degree of the future US commitment to the alliance with Japan and the level of China’s assertiveness.

Assessment of swelling and constituent redistribution in uranium-zirconium fuel using phenomena identification and ranking tables (PIRT)

Metallic alloy U-Zr nuclear fuels remain a candidate for future US fast reactors. However, with more than 30 years of investigation into the system, U-Zr fuel remains unqualified and lacks predictive modeling capabilities. Phenomenon identification and ranking tables (PIRT) were developed for U-Zr fuels to prioritize the study of microstructural phenomena related to fuel performance and to aid predictive models. Two areas of emphasis, fuel swelling and constituent redistribution, were identified with PIRT and were evaluated in detail. The analysis identified influencing parameters that should be considered during future studies including: external mechanical constraint, temperature, composition, crystallographic texture, temperature gradient, fabrication constraints, fission density, fission rate, initial porosity, and pre-irradiation grain size. The PIRT results support the need for a comprehensive study that focus on the decoupling of fission rate, irradiation temperature, and alloy composition to independently investigate the microstructural evolution in the multiple phases typical of advanced reactor conditions.

Developing a Personal Protective Equipment Selection Matrix for Preventing Occupational Exposure to Ebola Virus.

In response to the 2014 Ebola outbreak in West Africa and resulting cases in the United States, the Occupational Safety and Health Administration developed a personal protective equipment selection matrix to help employers protect workers from exposure to Ebola virus in the event of additional US cases. Now, the world's second largest Ebola outbreak on record continues to expand in the Democratic Republic of Congo, where more than 70 Ebola-infected healthcare workers serve as reminders of the importance of robust infection prevention measures in keeping infectious disease responders from becoming victims themselves. Toward facilitating preparedness for cases associated with the ongoing or future outbreaks, this article discusses the matrix of personal protective equipment recommendations. The matrix applies to a variety of job tasks in health care, laboratories, waste handling, janitorial services, travel and transportation, and other sectors where workers may be exposed to the Ebola virus during outbreak events. A discussion of the information sources and decision-making process for developing the matrix forms the basis of the recommendations. The article then emphasizes challenges and considerations for formulating the matrix, including identifying information sources to help characterize occupational exposures, aligning recommendations among stakeholders with varying viewpoints, and balancing worker protections with feasibility concerns. These considerations highlight issues that remain relevant for preparedness efforts ahead of future US cases of Ebola or other emerging infectious diseases.

Can energy prices predict stock returns? An extreme bounds analysis

We assess the predictive abilities of energy prices for future US stock market returns using Sala-i-Martin's (1997) extreme bounds analysis (EBA). The EBA results reveal that the predictive power of energy prices varies substantially across the regression models with different combinations of conditioning variables. Energy prices are not robust predictors for the stock returns in the whole sample period from June 1987 to April 2015. However, before the 2008 global financial crisis, energy prices exerted a moderate negative effect on future stock returns and their effects have become strongly positive afterwards. In general, the predictive power declines with the increase in forecast horizon and it varies considerably over time.

Containment’s deceit: why the United States needs to review its China strategy

Together with many other scholars of US containment, Brooks/Wohlforth share widely held assumptions on the future US–China relationship. Indeed, their arguments tempt American strategists into foregoing evaluations as the enduring US structural superiority, reflected in the strategy of “standing on the defensive”, reassures them that Beijing will be socialised to structural realities favouring the USA. However, China is not the Soviet Union and the twenty-first century’s second decade not the 1980s. Confusing the latter with today’s China and its highly adaptive governance system misrepresents a drastically changed politico-material context, as China has emerged as the leading economic power since 2014 (measured in PPP). Precisely because Brooks/Wohlforth adopt an exclusively material view, they overlook the notion of US cultural superiority which has invariably underpinned material accounts of containment. Thus, their material defence of America as “Number One” becomes a cognitive barrier, possibly self-defeating, to more comprehensive reviews of US technological superiority.

Significantly lower annual rates of neoplastic progression in short- compared to long-segment non-dysplastic Barrett's esophagus: a systematic review and meta-analysis.

Although shorter lengths of Barrett's esophagus (BE) have been associated with a lower risk of neoplastic progression, precise estimates have varied, especially for non-dysplastic BE (NDBE) only. Therefore, current US guidelines do not provide specific recommendations on surveillance intervals based on BE length. We performed a systematic review and meta-analysis of the published literature to examine neoplastic progression rates of NDBE based on BE length. PubMed, Cochrane, Google Scholar, and Embase were comprehensively searched. Studies reporting progression rates in patients with NDBE and > 1 year of follow-up were included. The number of patients progressing to esophageal adenocarcinoma (EAC) and high grade dysplasia (HGD)/EAC in individual studies and the mean follow-up were recorded to derive person-years of follow-up. Pooled rates of progression to EAC and HGD/EAC based on BE length (< 3 cm vs. ≥ 3 cm) were calculated. Of the 486 initial studies identified, 10 met the inclusion/exclusion criteria. These included a total of 4097 NDBE patients; 1979 with short-segment BE (SSBE; 10 773 person-years of follow-up) and 2118 with long-segment BE (LSBE; 12 868 person-years). The annual rates of progression to EAC were significantly lower for SSBE compared with LSBE: 0.06 % (95 % confidence interval 0.01 % - 0.10 %) vs. 0.31 % (0.21 % - 0.40 %), respectively; odds ratio (OR) 0.25 (0.11 - 0.56); P < 0.001, as were the rates for the combined endpoint (HGD/EAC): 0.24 % (0.09 % - 0.32 %) vs. 0.76 % (0.43 % - 0.89 %), respectively; OR 0.35 (0.21 - 0.58); P < 0.001. There was no significant heterogeneity among studies. The results demonstrate significantly lower rates of neoplastic progression in NDBE patients with SSBE compared with LSBE. BE length can easily be used for risk stratification purposes for NDBE patients undergoing surveillance endoscopy and consideration should be given to tailoring surveillance intervals based on BE length in future US guidelines.

«Красная угроза» как элемент внутренней политики США 1917—1920 годов: деятельность Бюро расследований Министерства юстиции

The article is devoted to the formation of the image of the “Red Menace” by the US Department of Justice in the early twentieth century. It is noted that the revolution in Russia in 1917 immediately riveted the attention of the American public and authorities, while the October revolution and the spread of Bolshevism in Russia provoked on the one hand, a negative reaction from the authorities, on the other hand, contributed to the activation of left-wing political forces in the United States. The purpose of the article is to trace how the Department of Justice and, in particular, the Bureau of Investigations (future FBI), which was gaining strength at the time, saw the implications of the Russian revolution for the internal security of the United States and built the image of this revolution as the “Red Menace”. It is shown that the most important events of this period are the so-called “Palmer raids” associated with the power actions of the Ministry of Justice and the Bureau of Investigation against anarchists, socialists and communists in the United States. It is noted that during this period, John Edgar Hoover, one of the main anti-Communists in US history, the future odious director of the FBI and one of the most influential people in the history of this country, began to work in the Ministry and the Bureau. The authors conclude that the “Red Menace” stereotype formed during the period under review will influence the future US policy towards Russia and during the Cold War.

American strategic performance towards Middle East in the era of president Trump - A future study

Abstract The strategic performance of the United States depends on dealing with the Middle East countries and its variants on several bases and motives that enabled them to achieve American hegemony and invest its interests at the expense of the region countries. Within this performance, the administration of the United State President Donald Trump presented the Strategic Document on December 18, 2017, which focused on the principle of "America First", to determine the direction of future US strategic performance in the formulation of means of cooperation and intersections or hostility in addition to interests and threats.The future vision of the Arab region and the Middle East as a whole, this strategy is based on the fact that it did not include any American commitment to promoting peace and stability in the world, especially the Middle East. According to that, American strategic performance will be directed towards multiple policies, including the policy of axes and crisis-making rather than resolving it and preventing stability for the preoccupation of major powers that seek to safeguard their interests and limit sovereignty or hegemony of the United State over the region.

Analyzing determinants of US distillers dried grains with solubles exports

AbstractThe exports of US distillers dried grains with solubles (DDGS), a coproduct of corn ethanol, have grown more than five‐fold over the last decade. However, there is limited knowledge of what factors drive US. DDGS exports and how those factors could impact future US DDGS exports. This study aimed to identify the determinants of US DDGS exports and estimate the growth of DDGS exports to major international buyers. A commodity‐specific gravity model was estimated using the pseudo‐Poisson maximum likelihood method for US DDGS exports to 29 countries over 2000–2013. Results suggest that the importing country’s meat production, technical barriers to trade, tariffs, and US ethanol production influence US DDGS exports. A baseline outlook for US DDGS exports to the six major importing countries through 2020 generated from the estimated gravity model shows China’s commodity and trade policy could have a vital impact on US DDGS exports. Variations in DDGS exports under the scenarios of high and low meat production in those importing countries were also derived.

Racial and ethnic estimates of Alzheimer's disease and related dementias in the United States (2015–2060) in adults aged ≥65 years

IntroductionAlzheimer's disease and related dementias (ADRD) cause a high burden of morbidity and mortality in the United States. Age, race, and ethnicity are important risk factors for ADRD. MethodsWe estimated the future US burden of ADRD by age, sex, and race and ethnicity by applying subgroup-specific prevalence among Medicare Fee-for-Service beneficiaries aged ≥65 years in 2014 to subgroup-specific population estimates for 2014 and population projection data from the United States Census Bureau for 2015 to 2060. ResultsThe burden of ADRD in 2014 was an estimated 5.0 million adults aged ≥65 years or 1.6% of the population, and there are significant disparities in ADRD prevalence among population subgroups defined by race and ethnicity. ADRD burden will double to 3.3% by 2060 when 13.9 million Americans are projected to have the disease. DiscussionThese estimates can be used to guide planning and interventions related to caring for the ADRD population and supporting caregivers.

Nationwide shift to grass-fed beef requires larger cattle population

In the US, there is growing interest in producing more beef from cattle raised in exclusively pasture-based systems, rather than grain-finishing feedlot systems, due to the perception that it is more environmentally sustainable. Yet existing understanding of the environmental impacts of exclusively pasture-based systems is limited by a lack of clarity about cattle herd dynamics. We model a nationwide transition from grain- to grass-finishing systems using demographics of present-day beef cattle. In order to produce the same quantity of beef as the present-day system, we find that a nationwide shift to exclusively grass-fed beef would require increasing the national cattle herd from 77 to 100 million cattle, an increase of 30%. We also find that the current pastureland grass resource can support only 27% of the current beef supply (27 million cattle), an amount 30% smaller than prior estimates. If grass-fed systems include cropland-raised forage, a definition that conforms to typical grass-fed certifications, these supplemental feeds can support an additional 34 million cattle to produce up to 61% of the current beef supply. Given the potential of forage feed croplands to compete with human food crop production, more work is required to determine optimal agricultural land uses. Future US demand in an entirely grass-and forage-raised beef scenario can only be met domestically if beef consumption is reduced, due to higher prices or other factors. If beef consumption is not reduced and is instead satisfied by greater imports of grass-fed beef, a switch to purely grass-fed systems would likely result in higher environmental costs, including higher overall methane emissions. Thus, only reductions in beef consumption can guarantee reductions in the environmental impact of US food systems.

Past role and future outlook of the Conservation Reserve Program for supporting honey bees in the Great Plains

Human dependence on insect pollinators continues to grow even as pollinators face global declines. The Northern Great Plains (NGP), a region often referred to as America's last honey bee (Apis mellifera) refuge, has undergone rapid land-cover change due to cropland expansion and weakened land conservation programs. We conducted a trend analysis and estimated conversion rates of Conservation Reserve Program (CRP) enrollments around bee apiaries from 2006 to 2016 and developed models to identify areas of habitat loss. Our analysis revealed that NGP apiaries lost over 53% of lands enrolled in the CRP, and the rate of loss was highest in areas of high apiary density. We estimated over 163,000 ha of CRP lands in 2006 within 1.6 km of apiaries was converted to row crops by 2012. We also evaluated how alternative scenarios of future CRP acreage caps may affect habitat suitability for supporting honey bee colonies. Our scenario revealed that a further reduction in CRP lands to 7.7 million ha nationally would reduce the number of apiaries in the NGP that meet defined forage criteria by 28% on average. Alternatively, increasing the national cap to 15 million ha would increase the number of NGP apiaries that meet defined forage criteria by 155%. Our scenarios also show that strategic placement of CRP lands near existing apiaries increased the number of apiaries that meet forage criteria by 182%. Our research will be useful for informing the potential consequences of future US farm bill policy and land management in the epicenter of the US beekeeping industry.

Trust But Verify: Donald Trump, Kim Jong Un and a Denuclearising North Korea after the Singapore Summit

The Trump–Kim Summit in Singapore can be regarded as a meaningful first step in a long journey towards complete denuclearisation of North Korea. At the Singapore summit, President Donald Trump and Chairman Kim Jong Un agreed that North Korea would denuclearise completely and that the United States would in return provide North Korea with security guarantees. However, due to political complexity of the North Korean nuclear issue and technical difficulties of nuclear dismantlement, the process towards complete denuclearisation of North Korea is expected to be protracted and difficult. The prospects for future US–North Korea nuclear negotiations will largely depend on how both countries can work out together the concrete steps, phases and timelines for the implementation of denuclearisation.

Hookah Use Among US Youth: A Systematic Review of the Literature From 2009 to 2017.

Given the US Food and Drug Administration (FDA)'s authority to regulate hookah, more research is needed to inform regulations intended to prevent youth from using hookah. This systematic review summarizes and assesses the literature related to hookah use among adolescents (11 to ≤18 years of age) in the United States from 2009 to 2017. Database searches yielded 867 peer-reviewed articles. After duplicates were removed, authors reviewed 461 articles for inclusion. Included articles (n = 55) were coded for study themes, study quality, and their relevance to FDA's research priorities. A qualitative synthesis is presented. The following themes were identified: (1) prevalence of hookah use (n = 42), (2) tobacco use transitions (n = 7), (3) sociodemographic correlates (n = 35), (4) psychosocial risk factors (n = 21), (5) concurrent use of other tobacco products (n = 31), (6) concurrent use of other substances (n = 9), and (7) other (n = 15)-which includes low prevalence themes. The qualitative synthesis showed increasing rates of hookah use. Older age, male gender, positive social normative beliefs, higher peer use, as well as lower perceived risk were associated with hookah use. Longitudinal studies of youth hookah use showed bidirectional relationships between use of hookah and other tobacco products. All articles fell within FDA's research priority related to "behavior," and three priorities ("impact analysis," "health effects," and "toxicity") have not been explored for hookah use among US youth since 2009. The prevalence of hookah use among youth in the United States is increasing, thus more research is needed to inform policies targeted to protect this vulnerable population. This study represents a novel contribution to our understanding of hookah use among youth in the United States from 2009-the year that the Family Smoking Prevention and Tobacco Control Act was passed-to 2017. In recent years, hookah has become a more popular tobacco product among US youth; however, to date, no systematic reviews of hookah use among this population exist. Results highlight implications for future US FDA regulatory policy and identify gaps in research to be addressed in future studies.

Assessing Fiscal Sustainability

Every country faces an intertemporal budget constraint, which requires that its government's future expenditures, including servicing its outstanding official debt, be covered by its government's future receipts when measured in present value. The present value difference between a country's future expenditures and its future receipts is its fiscal gap. The US fiscal gap now stands at $205 trillion. This is 10.3 percent of the estimated present value of all future US GDP. The United States needs to raise taxes, cut spending, or engage in a combination of these policies by an amount equal to 10.3 percent of annual GDP to close its fiscal gap. Closing the gap via raising taxes would require an immediate and permanent 57 percent increase in all federal taxes. Closing the gap via spending cuts (apart from servicing official debt) would require an immediate and permanent 37 percent reduction in spending. This grave picture of America's fiscal position effectively constitutes a declaration of bankruptcy.

Technical Specifications of Structural Health Monitoring for Highway Bridges: New Chinese Structural Health Monitoring Code

Governments and professional groups related to civil engineering write and publish standards and codes to protect the safety of critical infrastructure. In recent decades, countries have developed codes and standards for Structural Health Monitoring (SHM). During this same period, rapid growth in the Chinese economy has led to massive development of civil engineering infrastructure design and construction projects. Consequently, China has become the leading country of civil engineering. In 2016, the Ministry of Transportation of the People’s Republic of China published a new design code for SHM systems for large highway bridges. This document is the first technical SHM code by a national government that enforces sensor installation on highway bridges. This paper summarizes the existing international technical SHM codes for various countries and compares them with the new SHM code required by the Chinese Ministry of Transportation. The paper outlines the contents of the new Chinese SHM code and explains its relevance for the safety and management of large bridges in China, introducing key Chinese-US SHM vocabulary, definitions and technical significance. Finally, this paper discusses the implications for the design and implementation of a future US SHM code, with suggestions for similar efforts in other countries and governments.

Future southcentral US wildfire probability due to climate change

Globally, changing fire regimes due to climate is one of the greatest threats to ecosystems and society. In this paper, we present projections of future fire probability for the southcentral USA using downscaled climate projections and the Physical Chemistry Fire Frequency Model (PC2FM). Future fire probability is projected to both increase and decrease across the study region of Oklahoma, New Mexico, and Texas. Among all end-of-century projections, change in fire probabilities (CFPs) range from − 51 to + 240%. Greatest absolute increases in fire probability are shown for areas within the range of approximately 75 to 160 cm mean annual precipitation (MAP), regardless of climate model. Although fire is likely to become more frequent across the southcentral USA, spatial patterns may remain similar unless significant increases in precipitation occur, whereby more extensive areas with increased fire probability are predicted. Perhaps one of the most important results is illumination of climate changes where fire probability response (+, −) may deviate (i.e., tipping points). Fire regimes of southcentral US ecosystems occur in a geographic transition zone from reactant- to reaction-limited conditions, potentially making them uniquely responsive to different scenarios of temperature and precipitation changes. Identification and description of these conditions may help anticipate fire regime changes that will affect human health, agriculture, species conservation, and nutrient and water cycling.

Spatiotemporal changes in conterminous US wildfire exposure from 1940 to 2010

This study utilizes fine-scale, built-environment data in conjunction with past wildfire events to assess historical spatiotemporal changes in wildfire likelihood and societal exposure to wildfires for the conterminous USA. Results indicate that conterminous US wildfire exposure has increased substantially over the past 70 years due to escalating wildfire likelihood and an expanding human-developed footprint. Although wildfire exposure has increased as a whole throughout the conterminous USA, the relative contributions of wildfire likelihood and the built environment to exposure vary from region to region. Wildfire likelihood plays a larger role in exposure in the western USA due to a greater frequency of large wildfires. Conversely, built-environment density has a stronger influence on exposure than wildfire likelihood within the eastern and central USA. In all, the total number of homes and total developed land area prone to wildfire impacts has increased by nearly 1350% since 1940 throughout the conterminous USA. Findings presented in this study highlight the importance of considering both hazard likelihood and built-environment magnitude when assessing wildfire exposure. Given the rapid historical amplifications of both wildfire likelihood and societal exposure, communities in wildfire-prone areas should implement and/or continually evolve their existing wildfire prevention strategies to include the effects of expanding development to reduce future damages and losses. The continual enactment and adaptation of wildfire suppression and mitigation strategies will ultimately result in more disaster-resilient communities as climate and society continue to influence the future US wildfire exposure.