Proc Natl Acad Sci U S A
January 2025
There is a widespread perception that China's digital censorship distances its people from the global internet, and the Chinese Communist Party, through state-controlled media, is the main gatekeeper of information about foreign affairs. Our analysis of narratives about the Russo-Ukrainian War circulating on the Chinese social media platform Weibo challenges this view. Comparing narratives on Weibo with 8.
View Article and Find Full Text PDFHydrogels are hydrophilic 3-dimensional networks characterized by the retention of a large amount of water. Because of their water component, hydrogels are a promising method for targeted drug delivery. The water component, or "free volume", is a potential vehicle for protein drugs.
View Article and Find Full Text PDFMinimally invasive thoracic surgery has advanced the treatment of lung cancer since its introduction in the 1990s. Video-assisted thoracoscopic surgery (VATS) and robotic-assisted thoracic surgery (RATS) offer the advantage of smaller incisions without compromising patient outcomes. These techniques have been shown to be safe and effective in standard pulmonary resections (lobectomy and sub-lobar resection) and in complex pulmonary resections (sleeve resection and pneumonectomy).
View Article and Find Full Text PDFBackground And Aims: Water exchange (WE) and cap-assisted colonoscopy separately have been shown to reduce pain during insertion in unsedated patients. We hypothesized that compared with WE, WE cap-assisted colonoscopy (WECAC) could significantly lower real-time maximum insertion pain (RTMIP).
Methods: Veterans without escort were recruited, randomized, blinded, and examined at 3 U.
Proc Natl Acad Sci U S A
June 2024
Social media's pivotal role in catalyzing social movements is widely acknowledged across scientific disciplines. Past research has predominantly explored social media's ability to instigate initial mobilization while leaving the question of its capacity to sustain these movements relatively uncharted. This study investigates the persistence of movement activity on Twitter and Gab following a substantial on-the-ground mobilization event catalyzed by social media-the StoptheSteal movement culminating in the January 6th Capitol attack.
View Article and Find Full Text PDFWe study the effect of Facebook and Instagram access on political beliefs, attitudes, and behavior by randomizing a subset of 19,857 Facebook users and 15,585 Instagram users to deactivate their accounts for 6 wk before the 2020 U.S. election.
View Article and Find Full Text PDFCell shapes in tissues are affected by the biophysical interaction between cells. Tissue forces can influence specific cell features such as cell geometry and cell surface area. Here, we examined the 2-dimensional shape, size, and perimeter of pleural epithelial cells at various lung volumes.
View Article and Find Full Text PDFTargeted drug delivery to visceral organs offers the possibility of not only limiting the required dose, but also minimizing drug toxicity; however, there is no reliable method for delivering drugs to the surface of visceral organs. Here, we used six color tracers and the chick chorioallantoic membrane (CAM) model to investigate the use of the heteropolysaccharide pectin to facilitate tracer diffusion across the glycocalyceal charge barrier. The color tracers included brilliant blue, Congo red, crystal violet, indocyanine green, methylene blue, and methyl green.
View Article and Find Full Text PDFBackground: Changes in epithelial cell shape reflects optimal cell packing and the minimization of surface free energy, but also cell-cell interactions, cell proliferation, and cytoskeletal rearrangements.
Results: Here, we studied the structure of the rat pleura in the first 15 days after birth. After pleural isolation and image segmentation, the analysis demonstrated a progression of epithelial order from postnatal day 1 (P1) to P15.
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.
View Article and Find Full Text PDFMany critics raise concerns about the prevalence of 'echo chambers' on social media and their potential role in increasing political polarization. However, the lack of available data and the challenges of conducting large-scale field experiments have made it difficult to assess the scope of the problem. Here we present data from 2020 for the entire population of active adult Facebook users in the USA showing that content from 'like-minded' sources constitutes the majority of what people see on the platform, although political information and news represent only a small fraction of these exposures.
View Article and Find Full Text PDFWe studied the effects of exposure to reshared content on Facebook during the 2020 US election by assigning a random set of consenting, US-based users to feeds that did not contain any reshares over a 3-month period. We find that removing reshared content substantially decreases the amount of political news, including content from untrustworthy sources, to which users are exposed; decreases overall clicks and reactions; and reduces partisan news clicks. Further, we observe that removing reshared content produces clear decreases in news knowledge within the sample, although there is some uncertainty about how this would generalize to all users.
View Article and Find Full Text PDFDoes Facebook enable ideological segregation in political news consumption? We analyzed exposure to news during the US 2020 election using aggregated data for 208 million US Facebook users. We compared the inventory of all political news that users could have seen in their feeds with the information that they saw (after algorithmic curation) and the information with which they engaged. We show that (i) ideological segregation is high and increases as we shift from potential exposure to actual exposure to engagement; (ii) there is an asymmetry between conservative and liberal audiences, with a substantial corner of the news ecosystem consumed exclusively by conservatives; and (iii) most misinformation, as identified by Meta's Third-Party Fact-Checking Program, exists within this homogeneously conservative corner, which has no equivalent on the liberal side.
View Article and Find Full Text PDFWe investigated the effects of Facebook's and Instagram's feed algorithms during the 2020 US election. We assigned a sample of consenting users to reverse-chronologically-ordered feeds instead of the default algorithms. Moving users out of algorithmic feeds substantially decreased the time they spent on the platforms and their activity.
View Article and Find Full Text PDFBackground: Tracheobronchoplasty (TBP) is a definitive anatomic intervention for patients with severe symptomatic expiratory central airway collapse. Although stent evaluations have been described for surgical workup, current literature does not address if improvement during stent evaluation is sustained after TBP. We compared health-related quality of life (HRQOL) and functional status responses after airway stenting to those post-TBP.
View Article and Find Full Text PDFBackground And Aims: The 2012 and 2020 US Multi-Society Task Force postpolypectomy guidelines have recommended progressively longer surveillance intervals for patients with low-risk adenomas (LRAs). These guidelines require data from past colonoscopies. We examined the impact of the 2012 guidelines for second surveillance on clinical practice, including the availability of prior colonoscopy data, with the aim of informing the implementation of the 2020 guidelines.
View Article and Find Full Text PDFIntroduction: Currently, cold snare polypectomy (CSP) without submucosal injection is recommended for removing polyps < 10 mm. Use of viscous submucosal agents has not been previously evaluated in CSP. We investigate the potential role of EverLift™ (GI Supply, Pennsylvania) in CSP.
View Article and Find Full Text PDFIntroduction: Optimizing complete resection during colonoscopy is important because residual neoplastic tissue may play a role in interval cancers. The US Multi-Society Task Force recommends diminutive (≤5 mm) and small (6-9 mm) polyps be removed by cold snare polypectomy (CSP). However, evidence is less clear whether CSP retains significant advantage over cold forceps polypectomy (CFP) for polyps ≤3 mm.
View Article and Find Full Text PDFRepression research examines the causes and consequences of actions or policies that are meant to, or actually do, raise the costs of activism, protest, and/or social movement activity. The rise of digital and social media has brought substantial increases in attention to the repression of digital activists and movements and/or to the use of digital tools in repression, which is spread across many disciplines and areas of study. We organize and review this growing welter of research under the concept of digital repression by expanding a typology that distinguishes actions based on actor type, whether actions are overt or covert, and whether behaviors are shaped by coercion or channeling.
View Article and Find Full Text PDFBackground And Aims: There is a lack of convenient, sensitive, noninvasive strategies for screening and surveillance for colorectal neoplasia. An assay combining the results of circulating epithelial cells (CECs) and somatic mutations of cell-free DNA adjusting for age/sex using a unique algorithm is evaluated in patients requiring colonoscopy.
Methods: A prospective single-site 458-subject study (asymptomatic: 43% screening/43% surveillance, enriched with 65 symptomatic subjects undergoing colonoscopy) was conducted.
Background: Magnetic sphincter augmentation (MSA) is an effective treatment for gastroesophageal reflux disease (GERD). However, the impact of obesity on MSA outcomes is unknown. The objective of this study was to evaluate the effectiveness of MSA in patients with GERD and obesity.
View Article and Find Full Text PDFDigital experiences capture an increasingly large part of life, making them a preferred, if not required, method to describe and theorize about human behavior. Digital media also shape behavior by enabling people to switch between different content easily, and create unique threads of experiences that pass quickly through numerous information categories. Current methods of recording digital experiences provide only partial reconstructions of digital lives that weave - often within seconds - among multiple applications, locations, functions and media.
View Article and Find Full Text PDFIn 2015, the American Society for Gastrointestinal Endoscopy (ASGE) and American College of Gastroenterology (ACG) Task Force on Quality in Endoscopy deemed adenoma detection rate (ADR) the most important quality measure for colonoscopy. There has been much interest in factors that can increase ADR. To date, however, few studies have looked at what intra-procedural endoscopist practices are associated with improving ADR.
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