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1.
Proc Natl Acad Sci U S A ; 121(19): e2301436121, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38687798

ABSTRACT

Amid the discourse on foreign influence investigations in research, this study examines the impact of NIH-initiated investigations starting in 2018 on U.S. scientists' productivity, focusing on those collaborating with Chinese peers. Using publication data from 2010 to 2021, we analyze over 113,000 scientists and find that investigations coincide with reduced productivity for those with China collaborations compared to those with other international collaborators, especially when accounting for publication impact. The decline is particularly pronounced in fields that received greater preinvestigation NIH funding and engaged more in U.S.-China collaborations. Indications of scientist migration and broader scientific progress implications also emerge. We also offer insights into the underlying mechanisms via qualitative interviews.


Subject(s)
National Institutes of Health (U.S.) , China , United States , Humans , International Cooperation , Research Personnel/statistics & numerical data , Biomedical Research
2.
Sci Adv ; 9(44): eadg6799, 2023 11 03.
Article in English | MEDLINE | ID: mdl-37922349

ABSTRACT

Social media companies have come under increasing pressure to remove misinformation from their platforms, but partisan disagreements over what should be removed have stymied efforts to deal with misinformation in the United States. Current explanations for these disagreements center on the "fact gap"-differences in perceptions about what is misinformation. We argue that partisan differences could also be due to "party promotion"-a desire to leave misinformation online that promotes one's own party-or a "preference gap"-differences in internalized preferences about whether misinformation should be removed. Through an experiment where respondents are shown false headlines aligned with their own or the opposing party, we find some evidence of party promotion among Democrats and strong evidence of a preference gap between Democrats and Republicans. Even when Republicans agree that content is false, they are half as likely as Democrats to say that the content should be removed and more than twice as likely to consider removal as censorship.


Subject(s)
Politics , Social Media , Humans , United States , Employment
3.
Sci Adv ; 8(42): eabg2652, 2022 Oct 21.
Article in English | MEDLINE | ID: mdl-36260669

ABSTRACT

Text as data techniques offer a great promise: the ability to inductively discover measures that are useful for testing social science theories with large collections of text. Nearly all text-based causal inferences depend on a latent representation of the text, but we show that estimating this latent representation from the data creates underacknowledged risks: we may introduce an identification problem or overfit. To address these risks, we introduce a split-sample workflow for making rigorous causal inferences with discovered measures as treatments or outcomes. We then apply it to estimate causal effects from an experiment on immigration attitudes and a study on bureaucratic responsiveness.

4.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Article in English | MEDLINE | ID: mdl-35046018

ABSTRACT

Crisis motivates people to track news closely, and this increased engagement can expose individuals to politically sensitive information unrelated to the initial crisis. We use the case of the COVID-19 outbreak in China to examine how crisis affects information seeking in countries that normally exert significant control over access to media. The crisis spurred censorship circumvention and access to international news and political content on websites blocked in China. Once individuals circumvented censorship, they not only received more information about the crisis itself but also accessed unrelated information that the regime has long censored. Using comparisons to democratic and other authoritarian countries also affected by early outbreaks, the findings suggest that people blocked from accessing information most of the time might disproportionately and collectively access that long-hidden information during a crisis. Evaluations resulting from this access, negative or positive for a government, might draw on both current events and censored history.


Subject(s)
Access to Information , COVID-19/psychology , Information Seeking Behavior/physiology , Access to Information/legislation & jurisprudence , Access to Information/psychology , COVID-19/epidemiology , China/epidemiology , Humans , Political Systems , Politics , SARS-CoV-2 , Social Media/legislation & jurisprudence , Social Media/statistics & numerical data , Social Media/trends
5.
Nature ; 568(7753): 477-486, 2019 04.
Article in English | MEDLINE | ID: mdl-31019318

ABSTRACT

Machines powered by artificial intelligence increasingly mediate our social, cultural, economic and political interactions. Understanding the behaviour of artificial intelligence systems is essential to our ability to control their actions, reap their benefits and minimize their harms. Here we argue that this necessitates a broad scientific research agenda to study machine behaviour that incorporates and expands upon the discipline of computer science and includes insights from across the sciences. We first outline a set of questions that are fundamental to this emerging field and then explore the technical, legal and institutional constraints on the study of machine behaviour.


Subject(s)
Artificial Intelligence , Artificial Intelligence/legislation & jurisprudence , Artificial Intelligence/trends , Humans , Motivation , Robotics
6.
Science ; 345(6199): 1251722, 2014 Aug 22.
Article in English | MEDLINE | ID: mdl-25146296

ABSTRACT

Existing research on the extensive Chinese censorship organization uses observational methods with well-known limitations. We conducted the first large-scale experimental study of censorship by creating accounts on numerous social media sites, randomly submitting different texts, and observing from a worldwide network of computers which texts were censored and which were not. We also supplemented interviews with confidential sources by creating our own social media site, contracting with Chinese firms to install the same censoring technologies as existing sites, and--with their software, documentation, and even customer support--reverse-engineering how it all works. Our results offer rigorous support for the recent hypothesis that criticisms of the state, its leaders, and their policies are published, whereas posts about real-world events with collective action potential are censored.


Subject(s)
Blogging/legislation & jurisprudence , Communication , Crowding , Government Regulation , Social Media/legislation & jurisprudence , China , Humans
7.
Eur J Cardiothorac Surg ; 36(2): 236-42; discussion 242-3, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19394855

ABSTRACT

BACKGROUND: The mitral annulus (MA) is a dynamic structure that joins the left atrium (LA) and left ventricle (LV), but it is unknown whether MA motion is coupled to the LA or the LV or neither of the two. Since a well orchestrated coordination of LA, MA and LV septal-lateral (S-L) dynamics is essential for efficient valve closure, we assessed their functional coupling in an experimental ovine model. To assess the coupling under a wide range of physiological conditions, data were acquired in normal and acutely volume depleted hearts. METHODS: In 10 sheep, radiopaque markers were placed in LA, MA and LV base (LVbase). Twelve weeks postoperatively, 4-D marker coordinates were obtained by stereo videofluoroscopy (60 frames/s) before (CTRL) and during acute inferior vena caval occlusion (VCO). Septal-lateral dimensions were calculated as distances between corresponding marker pairs in the LA, MA and LVbase 5 frames before end-diastole (ED-84 ms) and at end-diastole. Dynamics during late diastole are described as changes from ED-84 ms versus end-diastole. To study the functional coupling between LA, MA and LVbase we calculated slopes during late diastole from simple linear regressions on an animal-by-animal basis. RESULTS: During late diastole in CTRL, the LA and MA both shortened along the S-L dimension (32.9 +/- 6.6 mm vs 31.0 +/- 5.5 mm, p = 0.026 and 27.3 +/- 3.7 mm vs 24.6 +/- 4.1 mm, p = 0.005, respectively) whereas the LVbase lengthened (56.2 +/- 9.3 mm vs 57.3 +/- 9.3 mm, p = 0.012). VCO abolished septal-lateral dynamics of LA and LVbase during late diastole (27.8 +/- 4.3 mm vs 27.4 +/- 3.9 mm, p = 0.155 and 49.4 +/- 7.7 mm vs 49.5 +/- 7.5 mm, p = 0.752, respectively) while the MA still shortened (19.0 +/- 2.9 vs 18.0 +/- 2.8, p = 0.042). Under CTRL conditions LA dynamics were linearly dependent from MA dynamics (average coefficient 0.57, p = 0.001), suggesting that LA and MA are functionally coupled. With acute volume depletion, MA dynamics were linearly independent from both, LA and LV (average coefficient 0.28, p = 0.159 and 0.58, p = 0.192, respectively). CONCLUSION: Whereas MA and LA dynamics are coupled during late diastole in hearts with normal LV volumes, presystolic mitral annular septal-lateral shortening is independent from LA and LV dynamics with acute volume depletion. A better understanding of mitral annular dynamics and their functional coupling may help improve mitral valve repair strategies.


Subject(s)
Hypovolemia/physiopathology , Mitral Valve/physiopathology , Myocardial Contraction/physiology , Acute Disease , Animals , Diastole/physiology , Disease Models, Animal , Heart Atria/physiopathology , Heart Ventricles/physiopathology , Hemodynamics/physiology , Male , Sheep , Systole/physiology
8.
Clin Endocrinol (Oxf) ; 67(3): 358-62, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17555502

ABSTRACT

BACKGROUND: AcroQol is a disease-generated questionnaire, developed to assess quality of life (QOL) in patients with acromegaly. We have previously demonstrated severely impaired QOL in patients with acromegaly and the value of AcroQol in measuring QOL in a cross-sectional study compared with the non-disease-specific generic tools 'Psychological general wellbeing schedule' (PGWBS) and EuroQol (EQ-5D), and the disease-specific signs and symptoms score (SSS). AIM, SUBJECTS AND METHODS: We re-evaluated these tools in a longitudinal study of 56 of the previously reported patients (33 male, mean age 55 +/- 15 years), in order to determine change in QOL over time and the effect of different treatment modalities. Data were analysed using Spearman's correlation tests. RESULTS: Baseline median IGF-I was 354 ng/ml (range 48-899) and at re-evaluation 217 ng/ml (60-594) (P < 0.001) [median time interval 608 days (113-1136)]. Analysis of change in IGF-I levels and AcroQol scores demonstrated a significant negative correlation (i.e. a reduction in IGF-I being associated with improved overall QOL (r = -0.36, P = 0.006). Significant negative correlations were also seen in the physical (r = -0.33, P = 0.01), psychological (r = -0.37, P = 0.005) and appearance (r = -0.42, P = 0.001) AcroQol subdomains. No correlations were seen between change in IGF-I and change in overall PGWBS score or subdomains, SSS or EQ-5D. CONCLUSIONS: In summary, of the tools studied we have demonstrated AcroQol to be uniquely capable of detecting changes in QOL associated with treatment-induced improvement in the main biochemical marker of disease activity in patients with acromegaly. Further studies are required to evaluate the long-term biological significance of the changes seen in AcroQol.


Subject(s)
Acromegaly/drug therapy , Acromegaly/psychology , Dopamine Agonists/therapeutic use , Quality of Life , Somatostatin/therapeutic use , Acromegaly/surgery , Adult , Aged , Combined Modality Therapy , Female , Health Status , Hormones/therapeutic use , Human Growth Hormone/analogs & derivatives , Human Growth Hormone/therapeutic use , Humans , Insulin-Like Growth Factor I/metabolism , Male , Middle Aged , Radiotherapy , Surveys and Questionnaires , Treatment Outcome
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