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1.
Health Commun ; : 1-10, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373894

RESUMEN

Research has repeatedly demonstrated the ability of social networks, interpersonal discussion, and perceived social norms to shape health-related outcomes. There are still substantial gaps, however, in understanding the theoretical mechanism that holds these components together, as well as the boundary conditions of their effects. Employing ego-network analysis with a representative sample of Illinois residents (N = 711) and focusing on the context of COVID-19 vaccine adherence, this study constructs a comprehensive framework to examine the direct, indirect, and conditional relationships linking social capital within networks, factual knowledge, and vaccination. Overall, the results point to the ability of tight-knit networks to influence knowledge and behavior for better or worse, depending on the composition of the network and its conversational valence. Theoretical and practical implications are discussed.

2.
Proc Natl Acad Sci U S A ; 119(25): e2119086119, 2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35700358

RESUMEN

Retracted papers often circulate widely on social media, digital news, and other websites before their official retraction. The spread of potentially inaccurate or misleading results from retracted papers can harm the scientific community and the public. Here, we quantify the amount and type of attention 3,851 retracted papers received over time in different online platforms. Comparing with a set of nonretracted control papers from the same journals with similar publication year, number of coauthors, and author impact, we show that retracted papers receive more attention after publication not only on social media but also, on heavily curated platforms, such as news outlets and knowledge repositories, amplifying the negative impact on the public. At the same time, we find that posts on Twitter tend to express more criticism about retracted than about control papers, suggesting that criticism-expressing tweets could contain factual information about problematic papers. Most importantly, around the time they are retracted, papers generate discussions that are primarily about the retraction incident rather than about research findings, showing that by this point, papers have exhausted attention to their results and highlighting the limited effect of retractions. Our findings reveal the extent to which retracted papers are discussed on different online platforms and identify at scale audience criticism toward them. In this context, we show that retraction is not an effective tool to reduce online attention to problematic papers.

3.
Nature ; 605(7908): 38-39, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35478016
4.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34544861

RESUMEN

Unbiased science dissemination has the potential to alleviate some of the known gender disparities in academia by exposing female scholars' work to other scientists and the public. And yet, we lack comprehensive understanding of the relationship between gender and science dissemination online. Our large-scale analyses, encompassing half a million scholars, revealed that female scholars' work is mentioned less frequently than male scholars' work in all research areas. When exploring the characteristics associated with online success, we found that the impact of prior work, social capital, and gendered tie formation in coauthorship networks are linked with online success for men, but not for women-even in the areas with the highest female representation. These results suggest that while men's scientific impact and collaboration networks are associated with higher visibility online, there are no universally identifiable facets associated with success for women. Our comprehensive empirical evidence indicates that the gender gap in online science dissemination is coupled with a lack of understanding the characteristics that are linked with female scholars' success, which might hinder efforts to close the gender gap in visibility.


Asunto(s)
Autoria/normas , Sistemas en Línea/normas , Revisión de la Investigación por Pares/tendencias , Publicaciones/normas , Ciencia/normas , Sexismo/prevención & control , Femenino , Humanos , Masculino
5.
PLoS One ; 13(3): e0193007, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29590131

RESUMEN

Peer-to-peer lending is hypothesized to help equalize economic opportunities for the world's poor. We empirically investigate the "flat-world" hypothesis, the idea that globalization eventually leads to economic equality, using crowdfinancing data for over 660,000 loans in 220 nations and territories made between 2005 and 2013. Contrary to the flat-world hypothesis, we find that peer-to-peer lending networks are moving away from flatness. Furthermore, decreasing flatness is strongly associated with multiple variables: relatively stable patterns in the difference in the per capita GDP between borrowing and lending nations, ongoing migration flows from borrowing to lending nations worldwide, and the existence of a tie as a historic colonial. Our regression analysis also indicates a spatial preference in lending for geographically proximal borrowers. To estimate the robustness for these patterns for future changes, we construct a network of borrower and lending nations based on the observed data. Then, to perturb the network, we stochastically simulate policy and event shocks (e.g., erecting walls) or regulatory shocks (e.g., Brexit). The simulations project a drift towards rather than away from flatness. However, levels of flatness persist only for randomly distributed shocks. By contrast, loss of the top borrowing nations produces more flatness, not less, indicating how the welfare of the overall system is tied to a few distinctive and critical country-pair relationships.


Asunto(s)
Organización de la Financiación/economía , Financiación Personal/economía , Inversiones en Salud/economía , Grupo Paritario , Algoritmos , Humanos , Modelos Económicos , Pobreza/economía , Pobreza/prevención & control
6.
PLoS One ; 11(4): e0152536, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27096435

RESUMEN

Many large network data sets are noisy and contain links representing low-intensity relationships that are difficult to differentiate from random interactions. This is especially relevant for high-throughput data from systems biology, large-scale ecological data, but also for Web 2.0 data on human interactions. In these networks with missing and spurious links, it is possible to refine the data based on the principle of structural similarity, which assesses the shared neighborhood of two nodes. By using similarity measures to globally rank all possible links and choosing the top-ranked pairs, true links can be validated, missing links inferred, and spurious observations removed. While many similarity measures have been proposed to this end, there is no general consensus on which one to use. In this article, we first contribute a set of benchmarks for complex networks from three different settings (e-commerce, systems biology, and social networks) and thus enable a quantitative performance analysis of classic node similarity measures. Based on this, we then propose a new methodology for link assessment called z* that assesses the statistical significance of the number of their common neighbors by comparison with the expected value in a suitably chosen random graph model and which is a consistently top-performing algorithm for all benchmarks. In addition to a global ranking of links, we also use this method to identify the most similar neighbors of each single node in a local ranking, thereby showing the versatility of the method in two distinct scenarios and augmenting its applicability. Finally, we perform an exploratory analysis on an oceanographic plankton data set and find that the distribution of microbes follows similar biogeographic rules as those of macroorganisms, a result that rejects the global dispersal hypothesis for microbes.


Asunto(s)
Modelos Teóricos , Algoritmos , Comercio , Plancton , Probabilidad , Red Social , Biología de Sistemas
7.
PLoS One ; 9(10): e108857, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25295877

RESUMEN

Traditional measures of success for film, such as box-office revenue and critical acclaim, lack the ability to quantify long-lasting impact and depend on factors that are largely external to the craft itself. With the growing number of films that are being created and large-scale data becoming available through crowd-sourced online platforms, an endogenous measure of success that is not reliant on manual appraisal is of increasing importance. In this article we propose such a ranking method based on a combination of centrality indices. We apply the method to a network that contains several types of citations between more than 40,000 international feature films. From this network we derive a list of milestone films, which can be considered to constitute the foundations of cinema. In a comparison to various existing lists of 'greatest' films, such as personal favourite lists, voting lists, lists of individual experts, and lists deduced from expert polls, the selection of milestone films is more diverse in terms of genres, actors, and main creators. Our results shed light on the potential of a systematic quantitative investigation based on cinematic influences in identifying the most inspiring creations in world cinema. In a broader perspective, we introduce a novel research question to large-scale citation analysis, one of the most intriguing topics that have been at the forefront of scientific enquiries for the past fifty years and have led to the development of various network analytic methods. In doing so, we transfer widely studied approaches from citation analysis to the the newly emerging field of quantification efforts in the arts. The specific contribution of this paper consists in modelling the multidimensional cinematic references as a growing multiplex network and in developing a methodology for the identification of central films in this network.

8.
PLoS One ; 8(9): e73413, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24039936

RESUMEN

Recent development of high-throughput, multiplexing technology has initiated projects that systematically investigate interactions between two types of components in biological networks, for instance transcription factors and promoter sequences, or microRNAs (miRNAs) and mRNAs. In terms of network biology, such screening approaches primarily attempt to elucidate relations between biological components of two distinct types, which can be represented as edges between nodes in a bipartite graph. However, it is often desirable not only to determine regulatory relationships between nodes of different types, but also to understand the connection patterns of nodes of the same type. Especially interesting is the co-occurrence of two nodes of the same type, i.e., the number of their common neighbours, which current high-throughput screening analysis fails to address. The co-occurrence gives the number of circumstances under which both of the biological components are influenced in the same way. Here we present SICORE, a novel network-based method to detect pairs of nodes with a statistically significant co-occurrence. We first show the stability of the proposed method on artificial data sets: when randomly adding and deleting observations we obtain reliable results even with noise exceeding the expected level in large-scale experiments. Subsequently, we illustrate the viability of the method based on the analysis of a proteomic screening data set to reveal regulatory patterns of human microRNAs targeting proteins in the EGFR-driven cell cycle signalling system. Since statistically significant co-occurrence may indicate functional synergy and the mechanisms underlying canalization, and thus hold promise in drug target identification and therapeutic development, we provide a platform-independent implementation of SICORE with a graphical user interface as a novel tool in the arsenal of high-throughput screening analysis.


Asunto(s)
Receptores ErbB/genética , Redes Reguladoras de Genes , MicroARNs/genética , Proteómica/métodos , Transducción de Señal , Algoritmos , Línea Celular Tumoral , Receptores ErbB/metabolismo , Regulación de la Expresión Génica , Humanos
9.
Bioinformatics ; 29(19): 2503-4, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23846745

RESUMEN

SUMMARY: Interactions between various types of molecules that regulate crucial cellular processes are extensively investigated by high-throughput experiments and require dedicated computational methods for the analysis of the resulting data. In many cases, these data can be represented as a bipartite graph because it describes interactions between elements of two different types such as the influence of different experimental conditions on cellular variables or the direct interaction between receptors and their activators/inhibitors. One of the major challenges in the analysis of such noisy datasets is the statistical evaluation of the relationship between any two elements of the same type. Here, we present SICOP (significant co-interaction patterns), an implementation of a method that provides such an evaluation based on the number of their common interaction partners, their so-called co-interaction. This general network analytic method, proved successful in diverse fields, provides a framework for assessing the significance of this relationship by comparison with the expected co-interaction in a suitable null model of the same bipartite graph. SICOP takes into consideration up to two distinct types of interactions such as up- or downregulation. The tool is written in Java and accepts several common input formats and supports different output formats, facilitating further analysis and visualization. Its key features include a user-friendly interface, easy installation and platform independence. AVAILABILITY: The software is open source and available at cna.cs.uni-kl.de/SICOP under the terms of the GNU General Public Licence (version 3 or later).


Asunto(s)
Diseño de Software , Algoritmos , ADN/metabolismo , Modelos Estadísticos , ARN/metabolismo , Distribución Aleatoria
10.
PLoS One ; 7(4): e34740, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22493713

RESUMEN

Members of social network platforms often choose to reveal private information, and thus sacrifice some of their privacy, in exchange for the manifold opportunities and amenities offered by such platforms. In this article, we show that the seemingly innocuous combination of knowledge of confirmed contacts between members on the one hand and their email contacts to non-members on the other hand provides enough information to deduce a substantial proportion of relationships between non-members. Using machine learning we achieve an area under the (receiver operating characteristic) curve (AUC) of at least 0.85 for predicting whether two non-members known by the same member are connected or not, even for conservative estimates of the overall proportion of members, and the proportion of members disclosing their contacts.


Asunto(s)
Apoyo Social , Inteligencia Artificial , Humanos , Distancia Psicológica , Curva ROC
11.
Mol Syst Biol ; 8: 570, 2012 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-22333974

RESUMEN

The EGFR-driven cell-cycle pathway has been extensively studied due to its pivotal role in breast cancer proliferation and pathogenesis. Although several studies reported regulation of individual pathway components by microRNAs (miRNAs), little is known about how miRNAs coordinate the EGFR protein network on a global miRNA (miRNome) level. Here, we combined a large-scale miRNA screening approach with a high-throughput proteomic readout and network-based data analysis to identify which miRNAs are involved, and to uncover potential regulatory patterns. Our results indicated that the regulation of proteins by miRNAs is dominated by the nucleotide matching mechanism between seed sequences of the miRNAs and 3'-UTR of target genes. Furthermore, the novel network-analysis methodology we developed implied the existence of consistent intrinsic regulatory patterns where miRNAs simultaneously co-regulate several proteins acting in the same functional module. Finally, our approach led us to identify and validate three miRNAs (miR-124, miR-147 and miR-193a-3p) as novel tumor suppressors that co-target EGFR-driven cell-cycle network proteins and inhibit cell-cycle progression and proliferation in breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Carcinoma/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Genes erbB-1/fisiología , MicroARNs/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma/metabolismo , Carcinoma/patología , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes/fisiología , Ensayos Analíticos de Alto Rendimiento , Humanos , Redes y Vías Metabólicas/genética , MicroARNs/fisiología , Modelos Biológicos , Unión Proteica/genética , Proteómica/métodos , Transcriptoma/genética , Transcriptoma/fisiología , Células Tumorales Cultivadas
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