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One of the greatest challenges in monitoring food security is to provide reliable crop yield information that is temporally consistent and spatially scalable. An ideal yield dataset would not only extend globally and across multiple years, but would also have enough spatial granularity to characterize productivity at the field and subfield level. Rapid increases in satellite data acquisition and platforms such as Google Earth Engine that can efficiently access and process vast archives of new and historical data offer an opportunity to map yields globally, but require efficient and robust algorithms to combine various data streams into yield estimates. We recently introduced a Scalable satellite-based Crop Yield Mapper (SCYM) that combines crop models simulations with imagery and weather data to generate 30 m resolution yield estimates without the need for ground calibration. In this study, we tested new large-scale implementations of SCYM, focusing on three regions with varying crops, field sizes and landscape heterogeneity: maize in the U.S. corn belt (390,000 km2), maize in Southern Zambia (86,000 km2), and wheat in northern India (450,000 km2). As a benchmark, we also tested a simpler empirical approach (PEAKVI) that relates yield to the peak value of a time series of spatially aggregated vegetation indices, similar to methods used in current operational monitoring. Both SCYM and PEAKVI were applied to data from all Landsat's sensors and MODIS for more than a decade in each region, and evaluated against ground-based estimates at the finest available administrative level (e.g., counties in the U.S.). We found consistently high correlations (R2 ≥ 0.5) between the spatial pattern of ground- and satellite-based estimates in both U.S. maize and India wheat, with small differences between methods and source of satellite data. In the U.S., SCYM outperformed PEAKVI in tracking temporal yield variations, likely owing to its explicit consideration of weather. In India, both methods failed to track temporal yield changes, with various possible explanations discussed. In Zambia, the PEAKVI approach applied to MODIS tracked yield variations much better (R2 > 0.5) than any other yield estimate, likely because the frequent cloud cover in this region confounds the other approaches. Overall, this study demonstrates successful approaches to yield estimation in each region, and illustrates the importance of distinguishing between accuracy for spatial and temporal variation. The 30 m resolution of Landsat-based SCYM does not appear to offer large benefits for tracking aggregate yields, but enables finer scale analyses than possible with the other approaches.

 

 

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George Azzari
David Lobell
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As immigration policy ideas dance around Washington, children’s health rarely enters the discussion. According to Stanford pediatrician Fernando Mendoza, new policies could have a huge impact on the well-being of children with immigrant parents.
 
“If you make them fearful on a day-to-day basis that their parents are going to be taken away, it causes tremendous stress on children and families,” said Mendoza, a professor of pediatrics at the Lucile Packard Children’s Hospital.

Mendoza has gathered experts across Stanford University and throughout California and the United States to address these issues at the Child Health and Immigration Conference on May 25. The panelists will discuss potential impacts at the federal, state and local level and advise communities on how to navigate the effects on children.
 
“All immigrants are having their place in this country challenged,” said Mendoza. “Whether or not you have a parent who is undocumented, that is detrimental to the well-being of the children of all immigrants.”
 
According to a study at the Pew Research Center, one out of every eight children in California lives with an undocumented parent.
 
“Policies that would remove those parents would probably be the biggest social disruption that we’ve seen in this country,” said Mendoza. “We need to have experts discuss these things so that we can have clarity about what the effects of national immigration policies might be.”
 
Immigration experts Jeffrey Passel, a senior demographer at the Pew Research Center, and Bill Hing, a professor of law at the University of San Francisco, will kick off the conference by outlining immigrant family demographics and the legal system for enforcing immigration policy.
 
They will be followed by panels of experts from Stanford and other academic institutions, policy-makers, and leaders in local health and educational systems.
 
U.S. Rep. Zoe Lofgren (D-San Jose) will bring the on-the-ground Washington perspective with a short appearance via video. A former immigration attorney, she will discuss congressional movement on immigration policy.
 
Mendoza said, “We all value children. This conference is trying to create common ground around that American value.”
 
The conference will be held May 25 at Stanford University in Encina Hall’s Bechtel Conference Center from 8:30 a.m. to 5:15 p.m. To attend, please RSVP here.
 
The conference is sponsored by Stanford’s Division of General Pediatrics; the Center for Policy, Outcomes and Prevention; and the Lucile Packard Foundation for Children’s Health.
 


MEDIA CONTACTS:

Fernando Mendoza, General Pediatrics: (650) 725-8314, fmendoza@stanford.edu

Nicole Feldman, Stanford Health Policy: (650) 725-3389, nicoletf@stanford.edu

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The Child Health and Immigration Conference will examine the impact of immigration policy on children. | Zara Abraham
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Stanford Health Policy’s Douglas K. Owens has been appointed vice chair of the U.S. Preventive Services Task Force, an independent, volunteer panel of national experts in prevention and evidence-based medicine.

Owens, the Henry J. Kaiser, Jr. Professor at Stanford University is a general internist at the VA Palo Alto Health Care System, and a professor of medicine, health research and policy, and management science and engineering at Stanford.

He is the director of the Center for Health Policy in the Freeman Spogli Institute for International Studies, where he is also a senior fellow, and the Center for Primary Care and Outcomes Research in the Department of Medicine and School of Medicine, and Associate Director of the Center for Innovation to Implementation at the VA Palo Alto Health Care System.

“Through his stellar work, Dr. Owens enables Stanford Medicine to advance its mission to precisely predict and prevent disease,” said Lloyd Minor, MD, dean of the Stanford School of Medicine. “As our country faces an increasingly diverse, aging patient population and rising health care costs, I am thrilled that Dr. Owens will contribute his perspective and expertise to this national task force.”

Owens served a previous four-year term on the independent, volunteer panel of national experts in prevention and evidence-based medicine. He will serve for two years as vice chair and then a year as chair. Members come from health-related fields ranging from internal medicine, family medicine, pediatrics, behavioral health, obstetrics/gynecology, and nursing.

The task force issues preventive care guidelines based on detailed assessment of the evidence about preventive interventions and is supported by the Agency for Healthcare Research and Quality within the U.S. Department of Health and Human Services.

“It’s humbling because the task force guidelines impact virtually every primary care patient in the United States,” said Owens, who is also past president of the Society for Medical Decision Making. “Having an unbiased, independent assessment of the benefits and harms of preventive services is very important for primary care clinicians and patients.”

The task force works to improve American’s health by making evidence-based recommendations about clinical preventive services such as screenings, counseling services and preventive medications. Its members have tackled everything from whether to screen for certain cancers, which medications should be taken to prevent diseases and reduce blood pressure and high cholesterol, and screening for infectious diseases, including HIV, HCV, TB, syphilis and other sexually transmitted diseases.

“We are honored to welcome Dr. Owens back to the task force in a leadership role,” said task force chair David C. Grossman, MD, MPH, a senior investigator and medical director for population health strategy at the Group Health Research Institute.

“His experience in guideline development, both with the task force and partner organizations, and his work in evidence-based medicine and clinical decision-making are valuable additions to our leadership team,” Grossman said.

The task force, for example, just released its draft guideline on prostate cancer screening. And some of the medical topics under development are screening for cervical and BRCA-related cancer, as well as pre-exposure prophylaxis for HIV infection.

Owens said that it was critical that the task force remains unbiased and independent. The 16 volunteer members who are nationally recognized experts in prevention, evidence-based medicine and primary care, carefully evaluate the science behind preventive interventions.

“The task force has very rigorous methods for assessing evidence, and we are fortunate to have state-of-the-art evidence reviews provided by AHRQ funded Evidence-Based Practice Centers,” he said.

Each year, the task force makes a report to Congress that identifies critical evidence gaps in research related to clinical prevention services and recommends priority areas that deserve further explanation. All their reports and recommendations are made public on the task force website and leave room for public comment.

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Rod Searcey
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Yong Suk Lee, deputy director of the Korea Program at Shorenstein APARC and SK Center Fellow at FSI, argues that "automation is significantly more important in explaining employment decline than import competition." The full article is available here.

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The Journal of General Internal Medicine (JGIM) has appointed Stanford Health Policy’s Steve Asch as an editor-in-chief.

JGIM is the highest rated journal for primary care research in the world. It publishes research on health services, implementation science, medical education and the humanities in addition to primary care.

Asch, a professor of medicine and the chief of health services research at the VA Palo Alto Healthcare System, joins two other editors-in-chief to screen articles and guide the journal’s direction.

“Steve is widely known as an outstanding writer and editor, and as having very broad methodological expertise,” said Douglas Owens, director of the Center for Health Policy/Primary Care and Outcomes Research. “He's a terrific choice to lead JGIM.”

Asch’s work focuses on quality improvement, and he has lead several national projects to develop tools that measure quality of care for veterans, Medicare users and the public. An avid mentor, Asch has trained dozens of physician fellows in health services research at Stanford and the VA system.

“We’re going to try to get research out there where it can make a difference in the world,” said Asch.

The editor team plans to focus more on best practices and implementation science. By combining the efforts of many researchers, they hope to ensure that doctors get the best answers to the big questions in health care.

“I think it’s going to be fun,” said Asch.

He looks forward to mentoring researchers to submit articles to journals like JGIM.

“Primary care is important,” said Asch. “As the health-care system transforms, it will play an increasingly important role, and the journal is very much in the lead in trying to publish new ways of organizing primary care.”

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May 25th Schedule for Child Health and Immigration Conference

Children in Immigrant Families and National Immigration Policy

 

8:30- 8:40        Welcome Drs. Mendoza, Sanders, and Wang

8:40-9:20       Demographics of Children in Immigrant Families

                          Jeffrey Passel, Ph.D., Senior Demographer, Hispanic Pew Research Center

9:20 -10:00    National Immigration Policy and Its Implications for Children in Immigrant Families

Bill Hing, JD, Professor of Law and Director of the Immigration and Deportation Defense Clinic, University of San Francisco, School of Law

Break 10 minutes

10:10- 11:10  Policy Research on CIF: Improving Health and Well Being (Duncan Lawrence, Ph.D.)

  Fernando Mendoza, MD, MPH – Professor of Pediatrics, Stanford University

                          Stanford Immigration Policy Lab

                                    Jens Hainmueller, Ph.D., Professor of Political Science

                                    David Laitin, Ph.D., Professor of Political Science

                                    Tomas Jimenez, Ph.D. – Associate Professor of Sociology

                          Florencia Torche, Ph.D. –Professor of Sociology, Stanford University

11:10 -12:10 Federal, State, and Regional Actions on Immigration Policy (Sherri Sager)

                          Zoe Lofgren, JD –(by video) Congresswoman 19th Congressional District, California

  Elizabeth Baca, MD, MPA, Sr. Health Advisor California Governor's Office of Planning and Research

  Jonathan Blazer, JD – Special Assistant Attorney General, California Dept. of Justice

  David Cortese, JD –President, Santa Clara County Board of Supervisors

12:10 -1:00 Lunch

 

Regional and Local Concerns for Children in Immigrant Families

 

1:00-2:20       Immigration and the Health and Educational Systems (David Alexander, MD)

                          Chris Dawes, MBA – CEO, Lucile Packard Children’s Hospital

                          Stephen Harris, MD – Santa Clara Valley Medical Center, Chair Dept. of Pediatrics

                          Reymundo Espinoza, MPH – Executive Director Gardner Family Health Network

                          Sara Cody, MD -Director, Public Health Department, Santa Clara County

                          Juan Cruz, MA– Superintendent, Franklin-McKinley School District

Break 10 minutes

 

2:30 -3:40       Health and Mental Health of Children in Immigrant Families (Yvonne Maldonado, MD)

                          Elena Fuentes Afflick , MD, MPH – Professor of Pediatrics, UCSF

                          Glenn Flores, MD – Chair, Health Policy Research, Medica Research Institute, .

                          Ryan Matlow, Ph.D. – Director of Community Research for Early Life Stress, Stanford

Break 10 minutes

 

3:50-4:50       Advocating for Children in Immigrant Families (Lee Sanders, MD)

                          Lisa Chamberlain, MD, MPH – Associate Professor of Pediatrics, Stanford; Director, Pediatric Advocacy Program

                          Maricela Gutierrez –Exe. Dir. Services, Immigration Rights, and Education Network

                          Dana Weintraub, MD - Assistant Professor; Medical Director, Peninsula Family Advocacy Program

                          Stacey Hawver, JD – Legal Director, Peninsula Family Advocacy Program

 

4:50 to 5:00    Closing Remarks –Fernando Mendoza, MD, MPH, -Professor of Pediatrics

 

5:00-6:00       Reception

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Abstract: The Cold War was about the rise and the solidification of US power. But it was also about more than that. It was about the defeat of Soviet-style Communism and the victory, in Europe, of a form of democratic consensus that had become institutionalized through the European Union. In China it meant a political and social revolution carried out by the Chinese Communist Party. In Latin America it meant the increasing polarization of societies along Cold War ideological lines of division. This book attempts to show the significance of the Cold War between capitalism and socialism on a world scale, in all its varieties and its sometimes confusing inconsistencies. As a one-volume history it can do little but scratch the surface of  complicated developments. But it will have served its purpose if it invites the reader to explore further the ways in which the Cold War made the world what it is today.

About the Speaker: Odd Arne Westad is the S.T. Lee Professor of U.S.-Asia Relations at Harvard University, where he teaches at the Kennedy School of Government. He is an expert on contemporary international history and on the eastern Asian region.  

Before coming to Harvard in 2015, Westad was School Professor of International History at the London School of Economics and Political Science (LSE). While at LSE, he directed LSE IDEAS, a leading centre for international affairs, diplomacy and strategy.
 
Professor Westad won the Bancroft Prize for The Global Cold War: Third World Interventions and the Making of Our Times. The book, which has been translated into fifteen languages, also won a number of other awards. Westad served as general editor for the three-volume Cambridge History of the Cold War, and is the author of the Penguin History of the World (now in its 6th edition). His most recent book, Restless Empire: China and the World since 1750, won the Asia Society’s book award for 2013.
Arne Westad Harvard University
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This event is a joint sponsorship between The Center for International Security and Cooperation and The Hoover Institution

About the Event: In this event, Professor Graham Allison will be interviewed by Niall Ferguson, Professor of History at Harvard University and a Senior Fellow at the Hoover Institution, about his new book, Thucydides’ Trap. In this book Allison argues that China and the United States are heading toward a war neither wants. Behind this dynamic is what Allison sees as a deadly pattern of structural stress that results when a rising power challenges a hegemon. This phenomenon is as old as history itself. About the Peloponnesian War that devastated ancient Greece, the historian Thucydides explained: “It was the rise of Athens and the fear that this instilled in Sparta that made war inevitable.” Over the past 500 years, these conditions have occurred sixteen times. War broke out in twelve of them. Today, as an unstoppable China approaches an immovable America and both Xi Jinping and Donald Trump promise to make their countries ‘great again,’ the seventeenth case looks grim. Unless China is willing to scale back its ambitions or Washington can accept becoming number two in the Pacific, a trade conflict, cyberattack, or accident at sea could soon escalate into all-out war (excerpt from www.amazon.com). Audience members will have an opportunity to ask questions after the conversation.

About the Speaker: Director of Harvard's Belfer Center for Science and International Affairs, Graham Allison is a leading analyst of U.S. national security and defense policy with a special interest in nuclear weapons, terrorism, and decision-making. As Assistant Secretary of Defense in the first Clinton Administration, Dr. Allison received the Defense Department's highest civilian award, the Defense Medal for Distinguished Public Service, for "reshaping relations with Russia, Ukraine, Belarus, and Kazakhstan to reduce the former Soviet nuclear arsenal." This resulted in the safe return of more than 12,000 tactical nuclear weapons from the former Soviet republics and the complete elimination of more than 4,000 strategic nuclear warheads previously targeted at the United States and left in Ukraine, Kazakhstan, and Belarus when the Soviet Union disappeared.

His latest book, Destined for War: Can America and China Escape Thucydides’s Trap?, will be published by Houghton Mifflin Harcourt in May 2017.  His 2013 book, Lee Kuan Yew: The Grand Master’s Insights on China, the United States and the World (co-authored with Robert Blackwill), has been a bestseller in the U.S. and abroad. Nuclear Terrorism: The Ultimate Preventable Catastrophe, now in its third printing, was selected by the New York Times as one of the "100 most notable books of 2004."  It presents a strategy for preventing nuclear terrorism organized under a doctrine of "Three Nos:" no loose nukes; no new nascent nukes; and no new nuclear weapons states. Dr. Allison's first book, Essence of Decision: Explaining the Cuban Missile Crisis (1971), was released in an updated and revised second edition (1999) and ranks among the all-time bestsellers with more than 450,000 copies in print.

Niall Ferguson is a senior fellow of the Hoover Institution, Stanford, and a senior fellow of the Center for European Studies, Harvard. He is also a visiting professor at Tsinghua University, Beijing, and the Diller-von Furstenberg Family Foundation Distinguished Scholar at the Nitze School of Advanced International Studies in Washington, DC. He has written fourteen books, including The House of Rothschild, Empire, The War of the World, The Ascent of Money, The Great Degeneration, and Kissinger, 1923-1968: The Idealist. His 2011 feature-length film Kissinger won the New York International Film Festival’s prize for best documentary. His PBS series The Ascent of Money won the International Emmy for best documentary. His many prizes and awards include the Benjamin Franklin Prize for Public Service (2010), the Hayek Prize for Lifetime Achievement (2012) and the Ludwig Erhard Prize for Economic Journalism (2013). He writes a weekly column for the London Sunday Times and the Boston Globe.

Graham Allison Professor of Government Belfer Center for Science and International Affairs, Harvard University
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Yiqun Chen and Tess Ryckman are the first students in the Stanford Health Policy PhD program to win research grants. Their projects could improve health outcomes in the United States and in the developing world.

“Awards like these are a recognition of the quality of our very young PhD program,” said Corinna Haberland, director of education for the PhD program that launched in 2015.

22940423679 43293bc87d o Yiqun Chen, Predoctoral Student

A member of the first class of doctoral candidates and currently in her second year, Chen received a seed grant from the Center on the Demography and Economics of Health and Aging (CDEHA). Funded by the National Institute on Aging (NIA), CDEHA studies how best to modify health care systems to adapt to aging populations.

Chen will study the Hospital Readmission Reduction Program. A component of the Affordable Care Act (ACA), the program encourages hospitals to keep readmission rates low, but the financial incentives do not extend to doctors. Chen will evaluate the program’s effectiveness for Medicare patients.

“Yiqun is well positioned to offer new insights into the ways that the organization of physicians and hospitals will influence quality improvement programs,” said Laurence Baker, chair of the Department of Health Research and Policy and the grant’s primary investigator.

tess raw adjustment Tess Ryckman, Predoctoral Student
Still in her first year of the PhD program, Ryckman managed to snag a coveted fellowship from the National Science Foundation (NSF). Their Graduate Research Fellowship Program (GRFP) supports outstanding graduate students pursuing degrees in science, technology, engineering and mathematics.

She plans to study nutrition in developing countries, focusing on the cost-effectiveness of programs that address stunting as compared to wasting. Two important public health indicators, stunting measures short height for age and wasting measures low weight for height.

“Wasting is more likely to result in death, but in a lot of countries the prevalence of wasting isn’t actually that high,” said Ryckman. “I suspect that in some cases they’re sacrificing funding that could go for stunting because wasting is more visible.”

The fellowship will allow Ryckman to focus on the research that inspires her. Instead of working as a TA or research assistant, she can pursue her own project while still drawing on faculty expertise.

“All of the faculty are really supportive,” she said. “They’re a helpful sounding board and give good advice.”

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