pinecone/core-2020-05-10-deduplication huggingface dataset:
Calibration and application of B/Ca, Cd/Ca, and δ11B in Neogloboquadrina pachyderma (sinistral) to constrain CO2 uptake in the subpolar North Atlantic during the last deglaciation

[1] The North Atlantic and Norwegian Sea are prominent sinks of atmospheric CO2 today, but their roles in the past remain poorly constrained. In this study, we attempt to use B/Ca and δ11B ratios in the planktonic foraminifera Neogloboquadrina pachyderma (sinistral variety) to reconstruct subsurface water pH and pCO2 changes in the polar North Atlantic during the last deglaciation. Comparison of core-top results with nearby hydrographic data shows that B/Ca in N. pachyderma (s) is mainly controlled by seawater B(OH)4−/HCO3− with a roughly constant partition coefficient inline image of 1.48 ± 0.15 × 10−3 (2σ), and δ11B in this species is offset below δ11B of the borate in seawater by 3.38 ± 0.71‰ (2σ). These values represent our best estimates with the sparse available hydrographic data close to our core-tops. More culturing and sediment trap work is needed to improve our understanding of boron incorporation into N. pachyderma (s). Application of a constant KD of 1.48 × 10−3 to high resolution N. pachyderma (s) B/Ca records from two adjacent cores off Iceland shows that subsurface pCO2 at the habitat depth of N. pachyderma (s) (~50 m) generally followed the atmospheric CO2 trend but with negative offsets of ~10–50 ppmv during 19–10 ka. These B/Ca-based reconstructions are supported by independent estimates from low-resolution δ11B measurements in the same cores. We also calibrate and apply Cd/Ca in N. pachyderma (s) to reconstruct nutrient levels for the same down cores. Like today's North Atlantic, past subsurface pCO2 variability off Iceland was significantly correlated with nutrient changes that might be linked to surface nutrient utilization and mixing within the upper water column. Because surface pCO2 (at 0 m water depth) is always lower than at deeper depths and if the application of a constant KD is valid, our results suggest that the polar North Atlantic has remained a CO2 sink during the calcification seasons of N. pachyderma (s) over the last deglaciation
Atlantic Water advection versus sea-ice advances in the eastern Fram Strait during the last 9 ka - multiproxy evidence for a two-phase Holocene

A sediment core from the West Spitsbergen continental margin was studied to reconstruct climate and paleoceanographic variability during the last ~9 ka in the eastern Fram Strait. Our multiproxy evidence suggests that the establishment of the modern oceanographic configuration in the eastern Fram Strait occurred stepwise, in response to the postglacial sea-level rise and the related onset of modern sea-ice production on the shallow Siberian shelves. The late Early and Mid Holocene interval (9 to 5 ka) was generally characterized by relatively unstable conditions. High abundance of the subpolar planktic foraminifer species Turborotalita quinqueloba implies strong intensity of Atlantic Water (AW) inflow with high productivity and/or high AW temperatures, resulting in a strong heat flux to the Arctic. A series of short-lived cooling events (8.2, 6.9. and 6.1 ka) occurred superimposed on the warm late Early and Mid Holocene conditions. Our proxy data imply that simultaneous to the complete postglacial flooding of Arctic shallow shelves and the initiation of modern sea-ice production, strong advance of polar waters initiated modern oceanographic conditions in the eastern Fram Strait at ~5.2 ka. The Late Holocene was marked by the dominance of the polar planktic foraminifer species Neogloboquadrina pachyderma, a significant expansion of sea ice/icebergs, and strong stratification of the water column. Although planktic foraminiferal assemblages as well as sea surface and subsurface temperatures suggest a return of slightly strengthened advection of subsurface Atlantic Water after 3 ka, a relatively stable cold-water layer prevailed at the sea surface and the study site was probably located within the seasonally fluctuating marginal ice zone during the Neoglacial period
Dansgaard-Oeschger cycles: Interactions between ocean and sea ice intrinsic to the Nordic seas

Dansgaard-Oeschger (D-O) cycles are the most dramatic, frequent, and wide-reaching
abrupt climate changes in the geologic record. On Greenland, D-O cycles are characterized
by an abrupt warming of 10 ± 5°C from a cold stadial to a warm interstadial phase, followed
by gradual cooling before a rapid return to stadial conditions. The mechanisms responsible
for these millennial cycles are not fully understood but are widely thought to involve abrupt
changes in Atlantic Meridional Overturning Circulation due to freshwater perturbations.
Here we present a new, high-resolution multiproxy marine sediment core monitoring
changes in the warm Atlantic inflow to the Nordic seas as well as in local sea ice cover and
influx of ice-rafted debris. In contrast to previous studies, the freshwater input is found to be
coincident with warm interstadials on Greenland and has a Fennoscandian rather than
Laurentide source. Furthermore, the data suggest a different thermohaline structure for the
Nordic seas during cold stadials in which relatively warm Atlantic water circulates beneath a
fresh surface layer and the presence of sea ice is inferred from benthic oxygen isotopes. This
implies a delicate balance between the warm subsurface Atlantic water and fresh surface
layer, with the possibility of abrupt changes in sea ice cover, and suggests a novel
mechanism for the abrupt D-O events observed in Greenland ice cores
Hydrographic changes in the tropical and extratropical Pacific during the last deglaciation

Fine-scale, paired Mg/Ca-δ18O profiles (Globigerinoides ruber white, sensu lato) from the San Lázaro Basin (SLB) at 25°N in the Northeast Pacific reveal a transition from a predominant presence of tropical/subtropical waters during the last glacial termination (T1) to an increasing influence of fresh and cold California Current waters toward the Holocene. Changing atmospheric circulation patterns over the Northeast Pacific in step with the demise of the Northern Hemisphere ice sheets and/or with a shift from El Niño- to La Niña-like conditions toward the Holocene are prime candidates to explain this water mass change. δ18OSW-IVC increases of ~0.5–0.7‰ during the Younger Dryas (YD) and Heinrich stadial 1 (HS1) at the SLB are observed in a number of δ18OSW-IVC records from the tropical Pacific, more directly influenced by changes in the position of the Intertropical Convergence Zone (ITCZ). Conditioning by ITCZ migration of the tropical Pacific Ocean towards salinity increase during YD and HS1, and the subsequent advection of those water masses as far north as 25°N likely accounted for the reconstructed hydrographical changes at the SLB. A larger influence of tropical water masses as far north as 25°N plausibly contributed to changes in the atmospheric moisture transports to western North America and affected the regional hydrological cycle across T1. Finally, the fine-scale resolution of our δ18OSW-IVC record allows pinpointing a shift from relative salty to fresh surface conditions at ~16.2 ka, signaling that the two-phase structure of HS1 is plausibly a ubiquitous feature of the northern tropical to extratropical ocean-atmosphere dynamics
Campanian-Maastrichtian ocean circulation in the tropical Pacific

The Pacific Ocean is the largest water body on Earth, and circulation in the Pacific\ud
contributed significantly to climate evolution in the latest Cretaceous, the culmination of a\ud
period of long-term cooling. Here, we present new high-resolution late Campanian to\ud
Maastrichtian benthic and planktic foraminiferal stable isotope data and a neodymium (Nd)\ud
isotope record obtained from sedimentary ferromanganese oxide coatings of Ocean Drilling\ud
Program Hole 1210B from the tropical Pacific Ocean (Shatsky Rise). These new records\ud
resolve 13 million years in the latest Cretaceous, providing insights into changes in surface\ud
and bottom water temperatures and source regions of deep to intermediate waters covering\ud
the carbon isotope excursions of the Campanian-Maastrichtian Boundary Event (CMBE)\ud
and the Mid-Maastrichtian event (MME). Our new benthic foraminiferal δ18O and Nd\ud
isotope records together with published Nd isotope data show markedly parallel trends\ud
across the studied interval over a broad range of bathyal to abyssal water depths interpreted\ud
to reflect changes in the intensity of deep-ocean circulation in the tropical Pacific. In\ud
particular, we observe a three-million-year-long period of cooler conditions in the early\ud
Maastrichtian (72.5 to 69.5 Ma) when a concomitant change toward less radiogenic\ud
seawater Nd isotope signatures probably marks a period of enhanced admixture and\ud
northward flow of deep waters with Southern Ocean provenance. We suggest this change to\ud
have been triggered by intensified formation and convection of deep waters in the high\ud
southern latitudes, a process that weakened during the MME (69.5 to 68.5 Ma). The early\ud
Maastrichtian cold interval is closely related to the negative and positive carbon isotope\ud
trends of the CMBE and MME. The millions-of-years long duration of these carbon cycle\ud
perturbations suggests a tectonic forcing of climatic cooling, possibly related to changes in\ud
ocean basin geometry and bathymetry
A "Politically Robust" Experimental Design for Public Policy Evaluation, with Application to the Mexican Universal Health Insurance Program

We develop an approach to conducting large scale randomized public policy experiments intended to be more robust to the political interventions that have ruined some or all parts of many similar previous efforts. Our proposed design is insulated from selection bias in some circumstances even if we lose observations; our inferences can still be unbiased even if politics disrupts any two of the three steps in our analytical procedures; and other empirical checks are available to validate the overall design. We illustrate with a design and empirical validation of an evaluation of the Mexican Seguro Popular de Salud (Universal Health Insurance) program we are conducting. Seguro Popular, which is intended to grow to provide medical care, drugs, preventative services, and financial health protection to the 50 million Mexicans without health insurance, is one of the largest health reforms of any country in the last two decades. The evaluation is also large scale, constituting one of the largest policy experiments to date and what may be the largest randomized health policy experiment ever.Governmen
Encryption and the Loss of Patient Data

Fast-paced IT advances have made it increasingly possible and useful for firms to collect data on their customers on an unprecedented scale. One downside of this is that firms can experience negative publicity and financial damage if their data are breached. This is particularly the case in the medical sector, where we find empirical evidence that increased digitization of patient data is associated with more data breaches. The encryption of customer data is often presented as a potential solution, because encryption acts as a disincentive for potential malicious hackers, and can minimize the risk of breached data being put to malicious use. However, encryption both requires careful data management policies to be successful and does not ward off the insider threat. Indeed, we find no empirical evidence of a decrease in publicized instances of data loss associated with the use of encryption. Instead, there are actually increases in the cases of publicized data loss due to internal fraud or loss of computer equipment.National Science Foundation (U.S.) (Grant 1053398
A preliminary theory of dark network resilience

A crucial contemporary policy question for governments across the globe is how to cope with international crime and terrorist networks. Many such “dark” networks—that is, networks that operate covertly and illegally—display a remarkable level of resilience when faced with shocks and attacks. Based on an in-depth study of three cases (MK, the armed wing of the African National Congress in South Africa during apartheid; FARC, the Marxist guerrilla movement in Colombia; and the Liberation Tigers of Tamil Eelam, LTTE, in Sri Lanka), we present a set of propositions to outline how shocks impact dark network characteristics (resources and legitimacy) and networked capabilities (replacing actors, linkages, balancing integration and differentiation) and how these in turn affect a dark network's resilience over time. We discuss the implications of our findings for policymakers
Is There An Association Between Gasoline Prices & Physical Activity?Evidence from American Time Use Data.

Obesity is epidemic in the U.S, and there is an imperative need to identify policy tools that may help fight this epidemic. A recent paper in the economics literature finds an inverse relationship between gasoline prices and obesity-risk --- suggesting that increased gasoline prices via higher gasoline taxes may have the effect of reducing obesity prevalence. This study builds upon that paper. It utilizes cross-sectional time-series data from the American Time Use Survey over 2003-2008, utilizes the increases that occurred in gasoline prices in this period due to Hurricane Katrina and to the global spike in gasoline prices as a ‘natural experiment’, and explores how time spent by Americans on different forms of physical activity is associated with gasoline price levels. 
	Economic theory suggests that higher gasoline prices may alter individual behavior both via a ‘substitution effect’ whereby people seek alternatives to motorized transportation, and an ‘income effect’ whereby the effect of higher gasoline prices on the disposable family budget lead people to make various adjustments to what they spend money on. The latter may lead to some increase in physical activity (for example, doing one’s own yard work instead of hiring help), but may also lead to decreases in other physical activities that involve expenses, such as team sports or work-outs at the gym. Thus, ultimately, the relationship between gasoline prices and physical activity must be empirically determined.
	Results from multivariate regression models with state and time fixed-effects indicate that higher gasoline prices are associated with an overall increase of physical activity that is at least moderately energy intensive. The increases are most pronounced in periods where gasoline prices fluctuate more sharply. These results appear robust to a number of model specifications. One of the major components of this increase appear to be an increase in housework that is at least moderately energy intensive – such as interior and exterior cleaning, garden and yard work, etc. This tentatively suggests that there is an ‘income effect’ of higher gasoline prices. However, the increases in physical activity associated with increased gasoline prices are weaker among minorities and low socioeconomic status (SES) individuals. Hence, while a policy which increases gasoline prices via raised gasoline taxes may have benefits in terms of increasing overall physical activity levels in the U.S., one concern is that these benefits may not accrue to low SES individuals to the same extent as to their higher SES counterparts.
Innovation Inducement Prizes: Connecting Research to Policy

Innovation inducement prizes have been used for centuries. In the United States, a recent federal policy change—the America COMPETES Reauthorization Act of 2010—clarified and simplified a path by which all federal agencies can offer innovation inducement prizes, thus intensifying interest in how government agencies can most effectively design and apply such prizes. This paper aims to review and synthesize the academic literature on innovation inducement prizes, to clarify what has been learned that is relevant to current policy discussions, and to highlight unresolved questions that would be fruitful areas for future academic research and policy experimentation. Relative to the existing literature, this paper aims to bridge two gaps. First, I synthesize the academic literature in this area with an eye toward drawing lessons for the types of innovation inducement prizes under consideration by federal agencies under the America COMPETES Reauthorization Act. Second, I discuss the problem of how to evaluate the success or failure of innovation inducement prizes, arguing that careful empirical evaluations of innovation inducement prizes are needed in order to provide guidance to federal agencies (and others) on how to most effectively apply and design innovation inducement prizes.National Institute on Aging (Grant Number: T32-AG000186
Growing Stem Cells: The Impact of Federal Funding Policy on the US Scientific Frontier

This paper articulates a citation-based approach to science policy evaluation and employs that approach to investigate the impact of the United States’ 2001 policy regarding the federal funding of human embryonic stem cell (hESC) research. We evaluate the impact of the policy on the level of U.S. hESC research, the U.S. position at the knowledge frontier, and the strategic response of U.S. scientists. Consistent with recent research on the science of science and innovation policy, we employ a difference-in-differences approach using bibliometric data with the aim of analyzing the causal impact of the policy on cumulative research. Our estimates suggest that in the aftermath of the 2001 policy, U.S. production of hESC research lagged 35 to 40 percent behind anticipated levels. However, this relative decline was largely concentrated in the years 2001 to 2003 and ameliorated over time. The rebound in U.S. hESC research after 2003 was driven by contributions by researchers at elite U.S. institutions and U.S. researchers who collaborated with international partners. The results suggest that scientists respond strategically to research funding restrictions and that modest science policy shifts can have a significant influence on the within-country composition of research and the pattern of global research collaboration.National Science Foundation (U.S.) (Grant Number: 0738394
Who Benefits from KIPP?

The nation's largest charter management organization is the Knowledge is Power Program (KIPP). KIPP schools are emblematic of the No Excuses approach to public education, a highly standardized and widely replicated charter model that features a long school day, an extended school year, selective teacher hiring, strict behavior norms, and emphasizes traditional reading and math skills. No Excuses charter schools are sometimes said to target relatively motivated high achievers at the expense of students who are more difficult to teach, including limited English proficiency (LEP) and special education (SPED) students, as well as students with low baseline achievement levels. We use applicant lotteries to evaluate the impact of KIPP Academy Lynn, a KIPP school in Lynn, Massachusetts that typifies the KIPP approach. Our analysis focuses on special needs students that may be underserved. The results show average achievement gains of 0.36 standard deviations in math and 0.12 standard deviations in reading for each year spent at KIPP Lynn, with the largest gains coming from the LEP, SPED, and low-achievement groups. Average reading gains are driven almost entirely by SPED and LEP students, whose reading scores rise by roughly 0.35 standard deviations for each year spent at KIPP Lynn
Spatial Regulation of Air Toxics Hot Spots

This paper analyzes the potential implications, in terms of net social costs and distribution of risks and abatement costs, of a policy to address the problem of air toxics “hot spots.” The policy we analyze involves regulation of air toxics sources at increasingly finer spatial resolutions. We develop a model of a decisionmaker choosing emission standards within a net cost minimization framework. Empirical application of the model to two counties in Florida demonstrates that regulation at finer resolutions could involve trade-offs between net social costs and equitable distribution of risks and, in some settings, between individual and population risks
IDENTIFYING MECHANISMS BEHIND POLICY INTERVENTIONS VIA CAUSAL MEDIATION ANALYSIS

Causal analysis in program evaluation has primarily focused on the question about whether or not a program, or package of policies, has an impact on the targeted outcome of interest. However, it is often of scientific and practical importance to also explain why such impacts occur. In this paper, we introduce causal mediation analysis, a statistical framework for analyzing causal mechanisms that has become increasingly popular in social and medical sciences in recent years. The framework enables us to show exactly what assumptions are sufficient for identifying causal mediation effects for the mechanisms of interest, derive a general algorithm for estimating such mechanism-specific effects, and formulate a sensitivity analysis for the violation of those identification assumptions. We also discuss an extension of the framework to analyze causal mechanisms in the presence of treatment noncompliance, a common problem in randomized evaluation studies. The methods are illustrated via applications to two intervention studies on pre-school classes and job-training workshops
Stretching fields and lines in the transport dynamics of the Western Mediterranean

2 pages, 2 figures.-- PAMM Special issue: "Sixth International Congress on Industrial Applied Mathematics (ICIAM07) and GAMM Annual Meeting, Zürich 2007".-- Full-text version available Open Access at: http://ifisc.uib.es/publications/downfile.php?fid=3612We summarize recent work on the location of Lagrangian structures in velocity fields obtained from realistic simulations and from satellite altimetry of the surface layers of the Mediterranean sea. Finite-size Lyapunov exponents are found to be useful quantities to characterize stretching and compressing structures, and their implications for mixing. Direct calculation of hyperbolic points and their stable and unstable manifolds identifies ocean structures, and allows the use of the tools of lobe dynamics to characterize fluid transport.Parts of this work have been supported by CSIC (grants PI-200650I224 and OCEANTECH), Royal Society-CSIC cooperation agreement (B2003GB03), MEC and FEDER (projects IMAGEN, CONOCE2 and FISICOS), ONR (Grant No. N00014-01-1-0769), and European Commission (projects MERSEA and 024717-DEMETRA).Peer reviewe
Rayleigh-Benard Convection in a Dielectric Liquid: Time-periodic Body Force

We discuss the thermal instability in a layer of dielectric fluid when the boundaries of the layer are subjected to small amplitude Time-periodic body force (TBF). Perturbation solution in powers of the amplitude of the applied temperature field is obtained using the Venezian method (1969) [1]. A linear stability analysis is performed. The results of the study, indicate that TBF or g-jitter leads to delayed convection Also for large frequencies the effect of TBF disappears.The problem has relevance in many dielectric fluid applications wherein regulation of thermal convection is called for. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim