The ratio of plant carbon gain to water use, known as water use efficiency (WUE), has long been recognized as a key constraint on crop production and an important target for crop improvement. WUE is a physiologically and genetically complex trait that can be defined at a range of scales. Many component traits directly influence WUE, including photosynthesis, stomatal and mesophyll conductances, and canopy structure. Interactions of carbon and water relations with diverse aspects of the environment and crop development also modulate WUE.
Although students in rural and migrant schools in China generally have not performed well, a share of each cohort has been able to thrive in school and to test into academic high school and college. To understand the origins of persistence, specifically, why some students learn more than do others, researchers have identified certain sources of the problem. Few studies, however, have paid attention to the role that low levels of cognitive development of students play in their academic performance.
Understanding the causes of economic inequality is critical for achieving equitable economic development. To investigate whether global warming has affected the recent evolution of inequality, we combine counterfactual historical temperature trajectories from a suite of global climate models with extensively replicated empirical evidence of the relationship between historical temperature fluctuations and economic growth. Together, these allow us to generate probabilistic country-level estimates of the influence of anthropogenic climate forcing on historical economic output.
Even as Notre Dame Cathedral was burning, pundits such as Ben Shapiro and Katie Hopkins began to mourn it as a “monument to Western civilization … built on the Judeo-Christian heritage” — describing the fire as symbolic of a “Judeo-Christian annihilation.” The president of Poland immediately called for rebuilding the cathedral as a symbolic reconstruction of Europe on its “
Linking individuals across historical datasets relies on information such as name and age that is both non-unique and prone to enumeration and transcription errors. These errors make it impossible to find the correct match with certainty. In the first part of the paper, we suggest a fully automated probabilistic method for linking historical datasets that enables researchers to create samples at the frontier of minimizing type I (false positives) and type II (false negatives) errors. The first step guides researchers in the choice of which varia-bles to use for linking.
We show that an information nudge increased the rate of American citizenship applications among low-income immigrants eligible for a federal fee waiver. Approximately half of the 9 million naturalization-eligible immigrants qualify for a federal programme that waives the cost of the citizenship application for low-income individuals.
Repetition is constitutive of human life. Both the species and the individual develop through repetition. Unlike simple recall, repetition is permeated by the past and the present and is oriented toward the future. Repetition of central actions and events plays an important role in the lives of individuals and the life of society. It helps to create meaning and memory. Because repetition is a central aspect of human life, it plays a role in all social and cultural spheres. It is important for several branches of the humanities and social studies.
What are the effects of international intervention on the rule of law after civil war? Rule of law requires not only that state authorities abide by legal limits on their power, but also that citizens rely on state laws and institutions to adjudicate disputes.
The 1940s and 1950s were a revolutionary era in both access to and imagination of the underwater environment in the most modernized nations of the globe. This article examines new possibilities in the exhibition of the underwater environment in film thanks to new dive and filming technologies. It focuses on how the depths are portrayed as a setting in Richard Fleischer’s 20,000 Leagues under the Sea (1954), by the Disney studio, and Jacques-Yves Cousteau and Louis Malle’s The Silent World (1956).
This paper examines how social isolation in a non-Anglophone context where English is not the main language of instruction for local students but is for international students, has unintended consequences for social capital formation among the latter. What factors influence international student network formation in such places where linguistic barriers are institutionalised and what are their consequences not only during college but beyond, in shaping students’ career plans?
In recent years, researchers have begun to focus attention on trying to identify systematic factors that cause interventions to have different impacts in different contexts. In this paper, we seek to understand whether the age of principals at schools implementing nutrition-based interventions has an impact on program outcomes. To explore the relative effectiveness of younger and older school principals, we use data from five large-scale, nutrition-related randomized controlled trials (RCTs) involving 12,595 primary school students in 336 schools in rural China. Our results, using two age cut-offs for distinguishing young principals from old ones, indicate that improvements in the health and nutrition outcomes of students were significantly higher in schools with younger principals than in schools run by older principals (when using a cutoff of 40 years old). When using a cut-off of 45 years old, the point estimates of the impacts similarly suggest that young principals are more effective, although the results are not significantly significant. The results are similar when we look at the impact of disaggregated interventions in schools managed by young and old principals. The findings are clear that the interventions implemented by older principals are not more effective than those implemented by younger principals.
This paper describes the current level of human capital in China and seeks to identify a number of education-related challenges that may slow down the nation’s economy from transitioning to high-income status. Relying on recent census-based data from OECD for the rest of the world and using data from the 2015 Micro-Census for China, the authors show that the low levels of education of China’s labour force is really a problem that has its roots in the past (in the 1970s, 1980s, and 1990s). In recent years (since 2000), China has been investing heavily in education as shown by the increasing the share of youth, including rural youth, attending high school. Despite this recent effort to raise the nation’s human capital, the education system still faces several challenges in trying to provide high-quality education for all youth. First, the government must figure out a way to overcome the relatively low rates of participation in high school by rural students. Second, there is concern that many vocational schools, especially those in rural areas, cannot deliver quality education. Finally, the paper will show that many rural students may be unprepared due to poor early childhood development outcomes.
The fruits of a long anticipated technology finally hit the market, with promise to extend human life, revolutionize production, improve consumer welfare, reduce poverty, and inspire countless yet-imagined innovations. A marvel of science and engineering, it reflects the cumulative efforts of a generation of researchers backed by research funding from the U.S. government and private sector investments in (predominantly American) technology companies.
From the end of the 12th century, crusading armies unleashed a relentless holy war against the indigenous pagan societies in the Eastern Baltic region. Native territories were reorganised as new Christian states (Livonia and Prussia) largely run by a militarised theocracy, dominated by the Teutonic Order. The new regime constructed castles, encouraged colonists, developed towns and introduced Christianity, incorporating the conquered territories into Latin Europe.
We assess and compare computer science skills among final-year computer science undergraduates (seniors) in four major economic and political powers that produce approximately half of the science, technology, engineering, and mathematics graduates in the world. We find that seniors in the United States substantially outperform seniors in China, India, and Russia by 0.76–0.88 SDs and score comparably with seniors in elite institutions in these countries. Seniors in elite institutions in the United States further outperform seniors in elite institutions in China, India, and Russia by ∼0.85 SDs. The skills advantage of the United States is not because it has a large proportion of high-scoring international students. Finally, males score consistently but only moderately higher (0.16–0.41 SDs) than females within all four countries.
There are plenty of indicators of doom: Donald Trump riding roughshod over U.S. constitutional norms; the rise of high-handed strongmen across Europe supported by ethno-centric crowds; free press and free voting under attack by cyber manipulation. Add mass migration threatening borders and national identities; rising wealth inequality; politics gridlocked by strife about rights, benefits, and duties, amidst growing resentment of "global elites" and new would-be citizens; and evolving confusion about the nature of the "common good."
By making available the almost unlimited energy stored in prehistoric plant matter, coal enabled the industrial age – and it still does. Coal today generates more electricity worldwide than any other energy source, helping to drive economic growth in major emerging markets. And yet, continued reliance on this ancient rock carries a high price in smog and greenhouse gases.
We assess scientific evidence that has emerged since the U.S. Environmental Protection Agency’s 2009 Endangerment Finding for six well-mixed greenhouse gases and find that this new evidence lends increased support to the conclusion that these gases pose a danger to public health and welfare.