Tucker, J., Guess, A., Barberá, P., Vaccari, C., Siegel, A., Sanovich, S., Stukal, D. & Nyhan, B. “Social Media, Political Polarization, and Political Disinformation: A Review of the Scientific Literature”, Report prepared for the Hewle Foundation, 2018.

Manuel Anselmi, Populism, social polarization and hybrid regimes: the case of Venezuela. In: Flaminia Saccà. Globalization and Socio-political New trends. (2016) p. 89-103, ROMA: Eurilink Edizioni Srl, ISBN:978-88-97931-81-2

Jennifer McCoy, Tahmina Rahman, and Murat Somer. “Polarization and the Global Crisis of Democracy: Common Patterns, Dynamics and Pernicious Consequences for Democratic Polities” in Special Issue on Polarization and Democracy: A Janus-faced Relationship with Pernicious Consequences, American Behavioral Scientist, 62:1 (January 2018): 16-42.

Abramowitz, Alan I. 2011. U.S. Senate Elections in an Age of Polarization. In Burdett Loomis, ed., The U.S. Senate: From Delay to Dysfunction, Washington, DC: Congressional Quarterly Press.

“The Logic of Polarizing Populism: State Crises and Polarization in South America,” Samuel Handlin, American Behavioral Scientist, 2018. Special issue on Polarization and Democracy.

Abramowitz, Alan I. 2007. Don’t Blame Primary Voters for Polarization. The Forum: A Journal of Applied Research in Contemporary Politics, Issue 4, Article 4.

Fluorescence emission intensity from a culture of rat skeletal muscle tissue cells (L6 cell line; myoblasts) that were immunofluorescently labeled with primary anti-bovine alpha-tubulin mouse monoclonal antibodies followed by goat anti-mouse Fab fragments conjugated to Alexa Fluor 430.

Fluorescence emission intensity from a culture of bovine pulmonary artery endothelial cells stained with DAPI, which targets DNA in the cell nucleus, is presented in Figure 2(c). The absorption maximum of DAPI (4',6-diamidino-2-phenylindole) is 358 nanometers and the emission maximum occurs at 461 nanometers when the fluorochrome is bound to DNA. In addition, the specimen was simultaneously stained with BODIPY FL phallacidin (targeting actin; green emission) and MitoTracker Red CMXRos (targeting mitochondria; red emission). Note the absence of signal from the red (MitoTracker) fluorophore, but bleed-through from the green (BODIPY FL) probe, which appears as a weak cyan signal surrounding the nuclei. In addition, the nuclei appear less intense and with fluorescence emission shifted to longer wavelengths than comparable images with the Nikon violet and ultraviolet filter combinations.

Abramowitz, Alan I. 2014. Long-Term Trends and Short-Term Forecasts: The Transformation of U.S. Presidential Elections in an Age of Polarization. PS: Political Science and Politics: 47, April: 289-292.

Autofluorescence emission intensity from a thin section of fern strobilus (Cyrtomium falcatum) tissue. Endogenous autofluorescence in plant tissues arises from a variety of biomolecules, including lignins, chlorophyll, carotene, and xanthophyll.

Cyan fluorescent proteinsequence

Jensen, C. & J.P.F. Thomsen (2011). “Can Party Competition Amplify Mass Ideological Polarization over Public Policy? The Case of Ethnic Exclusionism in Denmark and Sweden, Party Politics, 19(5): 821–840.

Wojcieszak, Magdalena & Winter, Stephan & Yu, Xudong. (2020). Social Norms and Selectivity: Effects of Norms of Open-Mindedness on Content Selection and Affective Polarization. Mass Communication and Society. 10.1080/15205436.2020.1714663.

Impact of Customizability Technology on Political Polarization — Dylko, Ivan; Dolgov, Igor; Hoffman, William; Eckhart, Nicholas; Molina, Maria; Aaziz, Omar; Journal of Information Technology & Politics, 02 January 2018, Vol.15(1), pp.19-33.

Wojcieszak, M. (2015). Political Polarization. In G. Mazzoleni (Ed.) International Encyclopedia of Political Communication. ICA Wiley-Blackwell International Encyclopedia. London: Wiley-Blackwell.

Political elites and immigration in Italy: party competition, polarization and new cleavages — D Di Mauro, L Verzichelli, Contemporary Italian Politics, 2019, 1-14.

Suiter, Jane & Fletcher, Richard. (2020). Polarization and partisanship: Key drivers of distrust in media old and new?. European Journal of Communication. 026732312090368. 10.1177/0267323120903685.

Polarization is reproduced in all political and social contexts with an intensity that distinguishes it from mere two-party politics, according to Palonen who says “It is a totalizing system, as it aims to dominate the existing systems of differences and identities. Similar logic can be found in other polarized contexts, such as those in the USA or Italy. The situation constitutes a problem for democracy insofar as democracy is seen as the articulation, combination and promotion of political values, demands and preferences that direct policies and seek to find a ground beyond the political elites, not mere regular elections.”

Barberá, P. “Social Media, Echo Chambers, and Political Polarization”, forthcoming. Social Media and Democracy: The State of the Field, edited by Nate Persily and Joshua Tucker. Cambridge University Press.

Jennifer McCoy & Murat Somer, Special Issue on Polarization and Democracy: A Janus-faced Relationship with Pernicious Consequences, American Behavioral Scientist, 62:1, January 2018.

« Back to Glossary IndexPolitical Polarization Political polarization can refer to the divergence of political attitudes to ideological extremes. Almost all discussions of polarization in political science consider polarization in the context of political parties and democratic systems of government. In most two-party systems, political polarization embodies the tension of its binary political ideologies and partisan identities. Mass polarization or popular polarization occurs when an electorate’s attitudes towards political issues, policies, and celebrated figures are neatly divided along party lines. At the extreme, each camp questions the moral legitimacy of the other, viewing the opposing camp and its policies as an existential threat to their way of life or the nation as a whole. Many political scientists consider political polarization a top-down process, in which elite polarization leads to — or at least precedes — popular polarization. Political polarization, according to an article by Emilia Palonen, is a political tool — articulated to demarcate frontiers between ‘us’ and ‘them’ and to stake out communities perceived as moral orders. Palonen writes that “polarization is a situation in which two groups create each other through demarcation of the frontier between them. The dominant political frontier creates a point of identification and confrontation in the political system, where consensus is found only within the political camps themselves.” Polarization is reproduced in all political and social contexts with an intensity that distinguishes it from mere two-party politics, according to Palonen who says “It is a totalizing system, as it aims to dominate the existing systems of differences and identities. Similar logic can be found in other polarized contexts, such as those in the USA or Italy. The situation constitutes a problem for democracy insofar as democracy is seen as the articulation, combination and promotion of political values, demands and preferences that direct policies and seek to find a ground beyond the political elites, not mere regular elections.” Palonen says that in polarization there is no middle ground. One has to choose sides. The political opponent is turned into an enemy, with an illegitimate and threatening position. Polarization also requires consensus on both sides of the main frontier, there is little space for diversity. Political polarization produces strong leaders due to the lack of contestation from within the party or coalition. They in turn secure their position by strengthening the polarization. This has been the main rhetorical strategy of Viktor Orban, a key populist politician in post-Communist Hungary, the leader of the Fidesz party. In the political rhetoric identities, symbols and history carry different meanings for the two poles. According to Palonen, the two camps of the bipolar hegemony sustain themselves through their opposition to one another rather than through their content. Polarization can be seen as a system of dual consensus, reproducing the typical problems of consensus. “Usually, but not exclusively, populism is attributed to small radical parties, which often rally on nationhood and anti-elitism, and are very successful in using media in order to put their message through,” says Palonen. “Alternatively, one of the main parties is seen as a populist. In Hungary there are two,” reminds Palonen and adds that “Populism is a hegemonic formation. They profess black-and-white rhetoric on the people and the elite, the tendential empty stances on values and policies and a stark confrontation with the political adversary. Post-Communist politics in Hungary are politics of a bipolar hegemony and competing populism. A ‘hegemonic formation’ fixes a maximum amount of meanings together or blocks them out of it. In the political rhetoric identities, symbols and history carry meanings for the two poles. The two camps of the bipolar hegemony sustain themselves through their opposition to one another rather than through their content. Polarization can be seen as a system of dual consensus, reproducing the typical problems of consensus.” According to Palonen, polarization solves the initial problem of fragmentation, lack of unity, by instituting a frontier that sustains two communities as a bipolar hegemony. It requires constant rearticulation and, therefore, constant antagonism on that frontier… “Similar to the one-party system or consensus, polarization and bipolar hegemony bracket out less important demands and maintain an illusion of unity, rejecting anything that might shake internal cohesion,” she underlines.  On the other hand, a World Bank report shows that many countries in Europe and Central Asia (ECA) are witnessing significant political polarization. Increasing numbers of voters appear to be moving away from centrist positions, abandoning long-held political commitments, and losing faith in established parties and to some extent institutions… Many issues — including economic difficulties, ethnic rivalries, the refugee crisis, and geopolitical tensions — may be driving political polarization in ECA. The importance of each varies by country. There does appear to have been some shift across ECA away from traditional, more centrist political parties, as well as toward more populist political opinions, since the beginning of this century. According to an article by Samuel Handlin, extremely polarized politics in countries such as Bolivia, Ecuador and Venezuela emerged through a mechanism termed polarizing populism, in which political outsiders leveraged popular anti-systemic appeals to underwrite otherwise risky and highly controversial policy programs. The occurrence (or not) of polarizing populism in South America, in turn, can be explained by the conjunction of state crises before the left turn period and the strength of the extant infrastructure of left-wing political mobilization each country possessed as the post–Cold War era began, which shaped incentives for outsiders to build ideologically narrow or broad elite coalitions. Handlin says highly polarizing party systems in South America emerged through a mechanism of ‘polarizing populism,’ distinguished by two characteristics: i) Populist figures and movements emerged to challenge for, and often win, executive power. ii) These populist figures not only politicized a pro-systemic/anti-systemic dimension of politics, but they also advanced radical programmatic agendas greatly at odds with those of status quo opponents. Meanwhile, a central claim of Hadlin’s article is that polarizing populism is enabled by state crises. State crises refer to situations characterized by two necessary elements: i) States perform poorly: Basic institutions such as the public administration, the judiciary, and the police prove inefficient and highly corrupt in their conduct and provision of goods and services. ii) Citizens come to possess very little confidence in these basic state institutions and government in general.  However, polarizing populism required not just state crisis but also contextual conditions that induced outsiders to build elite coalitions on the left. The proesses by which populist outsiders build movements, especially the coalitions and alliances they forge, therefore become critical in determining whether populists will adopt pragmatic or polarizing positions, and therefore whether or not they will transform party systems in highly polarizing directions. Read More Jennifer McCoy & Murat Somer, Special Issue on Polarization and Democracy: A Janus-faced Relationship with Pernicious Consequences, American Behavioral Scientist, 62:1, January 2018. Webster, Steven W., and Alan I. Abramowitz. 2017. The Ideological Foundations of Affective Polarization in the U.S. Electorate. American Politics Research 45: 621- 647. Alan Abramowitz and Jennifer McCoy, “United States: Racial Resentment, Negative Partisanship and Polarization in Trump’s America,” in Annals of American Academy of Political and Social Sciences, 681:1(January 2019): 137-156.  Abramowitz, Alan I. 2010. The Disappearing Center: Engaged Citizens, Polarization and American Democracy. New Haven: Yale University Press. Jennifer McCoy and Murat Somer, “Toward a Theory of Pernicious Polarization and How it Harms Democracy: Comparative Evidence and Possible Remedies,” in Annals of American Academy of Political and Social Sciences, 681, no. 1 (January 2019): 234-271. Abramowitz, Alan I. 2014. Long-Term Trends and Short-Term Forecasts: The Transformation of U.S. Presidential Elections in an Age of Polarization. PS: Political Science and Politics: 47, April: 289-292. Abramowitz, Alan I. I. 2010. Transformation and Polarization: The 2008 Presidential Election and the New American Electorate. Electoral Studies, 29: 594-603. Abramowitz, Alan I., and Kyle L. Saunders. 2008. Is Polarization a Myth? Journal of Politics, 70: 542-555. Abramowitz, Alan I. 2007. Don’t Blame Primary Voters for Polarization. The Forum: A Journal of Applied Research in Contemporary Politics, Issue 4, Article 4. Abramowitz, Alan I. and Walter J. Stone. 2006. The Bush Effect: Polarization, Turnout, and Activism in the 2004 Presidential Election. Presidential Studies Quarterly, 36: 141-154. Abramowitz, Alan I. 2017. It Wasn’t the Economy, Stupid: Racial Polarization, White Racial Resentment, and the Rise of Trump. In Larry Sabato, Kyle Kondik and Geoff Skelley, eds., Trumped: The 2016 Election that Broke All the Rules. New York: Rowman and Littlefield. Abramowitz, Alan I. 2015. The New American Electorate: Partisan, Sorted and Polarized. In James Thurber, ed., American Gridlock: The Sources, Character and Impact of Political Polarization. New York: Cambridge University Press. Abramowitz, Alan I. 2015. How Race and Religion Have Polarized American Voters. In Daniel J. Hopkins and John Sides, eds., Political Polarization in American Politics. New York: Bloomsbury Academic. Abramowitz, Alan I. 2015. Partisan Nation: The Rise of Affective Polarization in the American Electorate. In John Green, Daniel Coffey and David Cohen, eds., The State of the Parties: The Changing Role of Contemporary American Parties, 7th edition. New York: Rowman and Littlefield. Abramowitz, Alan I. 2013. Voting in a Time of Polarization: Why Barack Obama Won the 2012 Presidential Election and What It Means. In Larry J. Sabato, ed., Barack Obama and the New America: The 2012 Election and the Changing Face of Politics. New York: Rowman and Littlefield. Abramowitz, Alan I. 2012. Grand Old Tea Party: Partisan Polarization and the Rise of the Tea Party Movement. In Lawrence Rosenthal and Christine Trost, eds., Steep: The Precipitous Rise of the Tea Party. Berkeley: University of California Press. Abramowitz, Alan I. 2012. American Political Parties in an Age of Polarization. In Mark D. Brewer and L. Sandy Maisel, eds., The Parties Respond: Changes in American Parties and Campaigns, 5th edition. Boulder, CO: Westview Press. Abramowitz, Alan I. 2011. U.S. Senate Elections in an Age of Polarization. In Burdett Loomis, ed., The U.S. Senate: From Delay to Dysfunction, Washington, DC: Congressional Quarterly Press. Abramowitz, Alan I., and Kyle L. Saunders. 1997. Party Polarization and Ideological Realignment in the U.S. Electorate, 1976-1994. In L. Sandy Maisel, ed., The Parties Respond, 3rd edition. Boulder, Colorado: Westview Press. Stone, Walter J., Ronald B. Rapoport and Alan I. Abramowitz. 1990. The Reagan Revolution and Party Polarization in the 1980s. In L. Sandy Maisel, ed., The Parties Respond: Changes in the American Party System. Boulder, Colorado: Westview Press. Manuel Anselmi, Populism, social polarization and hybrid regimes: the case of Venezuela. In: Flaminia Saccà. Globalization and Socio-political New trends. (2016) p. 89-103, ROMA: Eurilink Edizioni Srl, ISBN:978-88-97931-81-2 Barberá, P. “Social Media, Echo Chambers, and Political Polarization”, forthcoming. Social Media and Democracy: The State of the Field, edited by Nate Persily and Joshua Tucker. Cambridge University Press. Tucker, J., Guess, A., Barberá, P., Vaccari, C., Siegel, A., Sanovich, S., Stukal, D. & Nyhan, B. “Social Media, Political Polarization, and Political Disinformation: A Review of the Scientific Literature”, Report prepared for the Hewle Foundation, 2018. Castanho Silva, Bruno. (2017). Populist radical right parties and mass polarization in the Netherlands. European Political Science Review. 10. 1-26. 10.1017/S1755773917000066. Polarization and partisanship: Key drivers of distrust in media old and new? — J Suiter, R Fletcher; European Journal of Communication, 0267323120903685 “Populist polarization and the slow death of democracy in Ecuador”, Carlos de la Torre, Andrés Ortiz,. Democratization, 23 (2) 2016, 221-241, DOI:10.1080/13510347.2015.1058784 Firat, Rengin B. and Pascal Boyer. 2015. “Coalitional Affiliation as a Missing Link Between Ethnic Polarization and Well-being: An Empirical Test from the European Social Survey.” Social Science Research, Vol. 53, pg. 148-161. Impact of Customizability Technology on Political Polarization — Dylko, Ivan; Dolgov, Igor; Hoffman, William; Eckhart, Nicholas; Molina, Maria; Aaziz, Omar; Journal of Information Technology & Politics, 02 January 2018, Vol.15(1), pp.19-33. Gulbrandsen, Trygve Jens & Hoffmann-Lange, Ursula (2007). Consensus or polarization? Business and Labour Elites in Germany and Norway, In Fredrik Engelstad & Trygve Jens Gulbrandsen (ed.), Comparative Studies of Social and Political Elites. Elsevier. ISBN 978-0-7623-1379-2. Samuel Handlin, State Crisis in Fragile Democracies: Polarization and Political Regimes in South America. Cambridge University Press, 2017. Somer, Murat, and Jennifer McCoy. “Transformations through Polarizations and Global Threats to Democracy.” The ANNALS of the American Academy of Political and Social Science 681, no. 1 (January, 2019): 8–22.  “The Logic of Polarizing Populism: State Crises and Polarization in South America,” Samuel Handlin, American Behavioral Scientist, 2018. Special issue on Polarization and Democracy. Murat Somer and Jennifer McCoy, “Introduction: Déjà vu? Polarization and Endangered Democracies in the 21st Century” in Special Issue on Polarization and Democracy: A Janus-faced Relationship with Pernicious Consequences, American Behavioral Scientist, 62:1, (January 2018): 3-15. Jennifer McCoy, Tahmina Rahman, and Murat Somer. “Polarization and the Global Crisis of Democracy: Common Patterns, Dynamics and Pernicious Consequences for Democratic Polities” in Special Issue on Polarization and Democracy: A Janus-faced Relationship with Pernicious Consequences, American Behavioral Scientist, 62:1 (January 2018): 16-42. Alban Lauka, Jennifer McCoy and Rengin B. Firat. “Mass Partisan Polarization: Measuring a Relational Concept” in Special Issue on Polarization and Democracy: A Janus-faced Relationship with Pernicious Consequences, American Behavioral Scientist, 62:1 (January 2018): 107-126. Where populist citizens get the news: An investigation of news audience polarization along populist attitudes in 11 countries — A Schulz; Communication Monographs, 2019, 86 (1), 88-111. Schmuck, D., Heiss, R., & Matthes, J. (2020). Drifting further apart? How exposure to media portrayals of Muslims affects attitude polarization. Political Psychology. Dynamics of Polarization in the Greek Case — Andreadis, Ioannis; Stavrakakis, Yannis; Mccoy, Jennifer (Editor); Somer, Murat (Editor); The ANNALS of the American Academy of Political and Social Science, January 2019, Vol.681(1), pp.157-172. Suiter, Jane & Fletcher, Richard. (2020). Polarization and partisanship: Key drivers of distrust in media old and new?. European Journal of Communication. 026732312090368. 10.1177/0267323120903685. Tucker, Joshua & Guess, Andrew & Barbera, Pablo & Vaccari, Cristian & Siegel, Alexandra & Sanovich, Sergey & Stukal, Denis & Nyhan, Brendan. (2018). Social Media, Political Polarization, and Political Disinformation: A Review of the Scientific Literature. SSRN Electronic Journal. 10.2139/ssrn.3144139. Jensen, C. & J.P.F. Thomsen (2011). “Can Party Competition Amplify Mass Ideological Polarization over Public Policy? The Case of Ethnic Exclusionism in Denmark and Sweden, Party Politics, 19(5): 821–840. P. Barberá, C. Vaccari, A. Valeriani (2017). ‘Social Media, Personalization of News Reporting, and Media Systems’ Polarization in Europe’. In M. Barisione, A. Michailidou (Eds), Social Media and European Politics: Rethinking Power and Legitimacy in the Digital Era. London: Palgrave Macmillan, ISBN: 978-1-137-59889-9, pp. 25-52. J. Tucker, A. Guess, P. Barbera, C. Vaccari, A. Siegel, S. Sanovich, D. Stukal, B. Nyhan (2018). Social Media, Political Polarization, and Political Disinformation: A Review of the Scientific Literature, commissioned by the Hewlett Foundation. Hameleers, M., & van der Meer, G. L. A. (2020). Misinformation and polarization in a high-choice media environment: How effective are political fact-checkers? Communication Research, 47, 227-250. https://doi.org/10.1177/0093650218819671 D.C. Trilling, M. van Klingeren & Y Tsfati (2016). Selective exposure, political polarization, and possible mediators: Evidence from the Netherlands. International Journal of Public Opinion Research.  Federico Vegetti, Zoltán Fazekas and Zsombor Méder. “Sorting your way out: perceived party posi- tions, political knowledge, and polarization.” 2017 Acta Politica, 52(4), 479–501. Political elites and immigration in Italy: party competition, polarization and new cleavages — D Di Mauro, L Verzichelli, Contemporary Italian Politics, 2019, 1-14. Wojcieszak, Magdalena & Winter, Stephan & Yu, Xudong. (2020). Social Norms and Selectivity: Effects of Norms of Open-Mindedness on Content Selection and Affective Polarization. Mass Communication and Society. 10.1080/15205436.2020.1714663. Wojcieszak, Magdalena & Garrett, R. Kelly. (2018). Social Identity, Selective Exposure, and Affective Polarization: How Priming National Identity Shapes Attitudes Toward Immigrants Via News Selection. Human Communication Research. 44. 10.1093/hcr/hqx010. Yang, JungHwan & Rojas, Hernando & Wojcieszak, Magdalena & Aalberg, Toril & Coen, Sharon & James, Curran & Hayashi, Kaori & Iyengar, Shanto & Jones, Paul & Mazzoleni, Gianpietro & Papathanassopoulos, Stylianos & Rhee, June & Rowe, David & Soroka, Stuart & Tiffen, Rodney. (2016). Why Are “Others” So Polarized? Perceived Political Polarization and Media Use in 10 Countries. Journal of Computer-Mediated Communication. 10.1111/jcc4.12166. Yang, J., Rojas, H., Wojcieszak, M., et al. (2016). Why are “others” so polarized? Perceived political polarization and media use in 10 countries. Journal of Computer-Mediated Communication, 21(5), 349- 367. Wojcieszak, M. (2011). Deliberation and Attitude Polarization. Journal of Communication 61, 596–617. Wojcieszak, M. (2015). Political Polarization. In G. Mazzoleni (Ed.) International Encyclopedia of Political Communication. ICA Wiley-Blackwell International Encyclopedia. London: Wiley-Blackwell. Press-party parallelism and polarization of news media during an election campaign: The case of the 2011 Turkish elections — A Çarkoğlu, L Baruh, K Yıldırım, The International Journal of Press/Politics, 2014, 19 (3), 295-317. Press-party parallelism and polarization of news media during an election campaign: The case of the 2011 Turkish elections — A Çarkoğlu, L Baruh, K Yıldırım, The International Journal of Press/Politics, 2014, 19 (3), 295-317. Related Articles: QAnon: A Conspiracy Cult or Quasi-Religion of Modern Times?Prof. Pappas: We need creative leaders with realistic agendas against populismReligious Populism, Cyberspace and Digital Authoritarianism in Asia: India, Indonesia, Malaysia, Pakistan, and TurkeyCivilizationist Populism in South Asia: Turning India SaffronCivilizational Populism Around the WorldRelated Terms:Term: Populist Radical RightTerm: Social MediaTerm: PopulismTerm: MediaTerm: The PeopleTerm: The EliteTerm: OutsidersTerm: Status Quo

Fluorescence emission intensity from a culture of rat thoracic aorta (muscle) cells that were immunofluorescently labeled with primary anti-oxphos complex V inhibitor protein monoclonal antibodies (mouse) followed by goat anti-mouse Fab fragments conjugated to Pacific Blue.

Abramowitz, Alan I. 2015. Partisan Nation: The Rise of Affective Polarization in the American Electorate. In John Green, Daniel Coffey and David Cohen, eds., The State of the Parties: The Changing Role of Contemporary American Parties, 7th edition. New York: Rowman and Littlefield.

Abramowitz, Alan I. 2017. It Wasn’t the Economy, Stupid: Racial Polarization, White Racial Resentment, and the Rise of Trump. In Larry Sabato, Kyle Kondik and Geoff Skelley, eds., Trumped: The 2016 Election that Broke All the Rules. New York: Rowman and Littlefield.

Abramowitz, Alan I. I. 2010. Transformation and Polarization: The 2008 Presidential Election and the New American Electorate. Electoral Studies, 29: 594-603.

According to an article by Samuel Handlin, extremely polarized politics in countries such as Bolivia, Ecuador and Venezuela emerged through a mechanism termed polarizing populism, in which political outsiders leveraged popular anti-systemic appeals to underwrite otherwise risky and highly controversial policy programs. The occurrence (or not) of polarizing populism in South America, in turn, can be explained by the conjunction of state crises before the left turn period and the strength of the extant infrastructure of left-wing political mobilization each country possessed as the post–Cold War era began, which shaped incentives for outsiders to build ideologically narrow or broad elite coalitions.

Press-party parallelism and polarization of news media during an election campaign: The case of the 2011 Turkish elections — A Çarkoğlu, L Baruh, K Yıldırım, The International Journal of Press/Politics, 2014, 19 (3), 295-317.

Abramowitz, Alan I. 2015. How Race and Religion Have Polarized American Voters. In Daniel J. Hopkins and John Sides, eds., Political Polarization in American Politics. New York: Bloomsbury Academic.

Mass polarization or popular polarization occurs when an electorate’s attitudes towards political issues, policies, and celebrated figures are neatly divided along party lines. At the extreme, each camp questions the moral legitimacy of the other, viewing the opposing camp and its policies as an existential threat to their way of life or the nation as a whole. Many political scientists consider political polarization a top-down process, in which elite polarization leads to — or at least precedes — popular polarization.

Polarization and partisanship: Key drivers of distrust in media old and new? — J Suiter, R Fletcher; European Journal of Communication, 0267323120903685

Dynamics of Polarization in the Greek Case — Andreadis, Ioannis; Stavrakakis, Yannis; Mccoy, Jennifer (Editor); Somer, Murat (Editor); The ANNALS of the American Academy of Political and Social Science, January 2019, Vol.681(1), pp.157-172.

Abramowitz, Alan I. 2013. Voting in a Time of Polarization: Why Barack Obama Won the 2012 Presidential Election and What It Means. In Larry J. Sabato, ed., Barack Obama and the New America: The 2012 Election and the Changing Face of Politics. New York: Rowman and Littlefield.

CFP excitation Wavelength

The CFP fluorescence filter set is designed for optimum performance with cyan fluorescent protein excited by blue-violet wavelengths, in particular when utilized for dual labeling techniques in combination with enhanced yellow fluorescent protein. Although originally designed to detect emission from the protein fluorophore, this filter combination is essentially a bandpass emission blue-violet excitation set and can be utilized to examine a wide spectrum of specimens that absorb light in this spectral region.

D.C. Trilling, M. van Klingeren & Y Tsfati (2016). Selective exposure, political polarization, and possible mediators: Evidence from the Netherlands. International Journal of Public Opinion Research.

Federico Vegetti, Zoltán Fazekas and Zsombor Méder. “Sorting your way out: perceived party posi- tions, political knowledge, and polarization.” 2017 Acta Politica, 52(4), 479–501.

In the political rhetoric identities, symbols and history carry different meanings for the two poles. According to Palonen, the two camps of the bipolar hegemony sustain themselves through their opposition to one another rather than through their content. Polarization can be seen as a system of dual consensus, reproducing the typical problems of consensus. “Usually, but not exclusively, populism is attributed to small radical parties, which often rally on nationhood and anti-elitism, and are very successful in using media in order to put their message through,” says Palonen.

Cyan fluorescent proteinstructure

Stone, Walter J., Ronald B. Rapoport and Alan I. Abramowitz. 1990. The Reagan Revolution and Party Polarization in the 1980s. In L. Sandy Maisel, ed., The Parties Respond: Changes in the American Party System. Boulder, Colorado: Westview Press.

Autofluorescence emission intensity from a thin section of fern strobilus (Cyrtomium falcatum) tissue is demonstrated in Figure 2(f). Endogenous autofluorescence in plant tissues arises from a variety of biomolecules, including lignins, chlorophyll, carotene, and xanthophyll. In the blue-violet region, chlorophyll has an absorption band with a high extinction coefficient and produces a significant amount of fluorescence when excited with wavelengths between 400 and 440 nanometers. Note the absence of spectral bleed-through from autofluorescence emission in the green and red spectral regions with the CFP filter combination.

Cyan fluorescent proteinsize

Murat Somer and Jennifer McCoy, “Introduction: Déjà vu? Polarization and Endangered Democracies in the 21st Century” in Special Issue on Polarization and Democracy: A Janus-faced Relationship with Pernicious Consequences, American Behavioral Scientist, 62:1, (January 2018): 3-15.

Figure 2(e) illustrates the emission intensity from a culture of rat kangaroo kidney epithelial cells (PtK2 line) that were immunofluorescently labeled with primary anti-cytokeratin (an intermediate filament protein) mouse monoclonal antibodies followed by goat anti-mouse Fab fragments conjugated to Marina Blue. The absorption maximum of Marina Blue is 365 nanometers and the emission maximum occurs at 460 nanometers. In addition, the specimen was simultaneously stained for mitochondria with MitoTracker Red CMXRos. Note the absence of signal from the red fluorophore with this bandpass emission filter combination. It should also be mentioned that the lack of significant absorption for Marina Blue in the blue-violet region results in a comparatively weak signal with the CFP filter set.

Yellowfluorescent protein

Cyan Fluorescent Proteinspectrum

Palonen says that in polarization there is no middle ground. One has to choose sides. The political opponent is turned into an enemy, with an illegitimate and threatening position. Polarization also requires consensus on both sides of the main frontier, there is little space for diversity. Political polarization produces strong leaders due to the lack of contestation from within the party or coalition. They in turn secure their position by strengthening the polarization. This has been the main rhetorical strategy of Viktor Orban, a key populist politician in post-Communist Hungary, the leader of the Fidesz party.

Where populist citizens get the news: An investigation of news audience polarization along populist attitudes in 11 countries — A Schulz; Communication Monographs, 2019, 86 (1), 88-111.

P. Barberá, C. Vaccari, A. Valeriani (2017). ‘Social Media, Personalization of News Reporting, and Media Systems’ Polarization in Europe’. In M. Barisione, A. Michailidou (Eds), Social Media and European Politics: Rethinking Power and Legitimacy in the Digital Era. London: Palgrave Macmillan, ISBN: 978-1-137-59889-9, pp. 25-52.

Yang, JungHwan & Rojas, Hernando & Wojcieszak, Magdalena & Aalberg, Toril & Coen, Sharon & James, Curran & Hayashi, Kaori & Iyengar, Shanto & Jones, Paul & Mazzoleni, Gianpietro & Papathanassopoulos, Stylianos & Rhee, June & Rowe, David & Soroka, Stuart & Tiffen, Rodney. (2016). Why Are “Others” So Polarized? Perceived Political Polarization and Media Use in 10 Countries. Journal of Computer-Mediated Communication. 10.1111/jcc4.12166.

Schmuck, D., Heiss, R., & Matthes, J. (2020). Drifting further apart? How exposure to media portrayals of Muslims affects attitude polarization. Political Psychology.

Handlin says highly polarizing party systems in South America emerged through a mechanism of ‘polarizing populism,’ distinguished by two characteristics: i) Populist figures and movements emerged to challenge for, and often win, executive power. ii) These populist figures not only politicized a pro-systemic/anti-systemic dimension of politics, but they also advanced radical programmatic agendas greatly at odds with those of status quo opponents.

Nuclei in a mouse kidney thin tissue section (Figure 2(d)) were targeted with the nucleic acid probe DAPI, which has an excitation maximum at 358 nanometers and an emission maximum at 461 nanometers when bound to DNA in cell cultures and tissue sections. In addition, the cryostat section in Figure 2(d) was also simultaneously stained with Alexa Fluor 488 wheat germ agglutinin (glomeruli and convoluted tubules) and Alexa Fluor 568 phalloidin (filamentous actin and the brush border). Note the absence of signal from the red (Alexa Fluor 568) fluorophore, but the significant amount of bleed-through into the cyan emission filter from the green (Alexa Fluor 488) probe. With an ultraviolet excitation bandpass emission filter set, the darker nuclei in the specimen would appear bright blue and the signal from Alexa Fluor 488 would be largely absent.

Nikon offers a wide range of fluorescence filter cubes with high fluorescence acquisition efficiency to support imaging of a large variety of fluorophores and fluorescent proteins.

“Populist polarization and the slow death of democracy in Ecuador”, Carlos de la Torre, Andrés Ortiz,. Democratization, 23 (2) 2016, 221-241, DOI:10.1080/13510347.2015.1058784

Wojcieszak, Magdalena & Garrett, R. Kelly. (2018). Social Identity, Selective Exposure, and Affective Polarization: How Priming National Identity Shapes Attitudes Toward Immigrants Via News Selection. Human Communication Research. 44. 10.1093/hcr/hqx010.

The excitation bandpass of the CFP combination does not generally excite yellow fluorescent protein (excited at 513 nanometers), and by employing a bandpass emission filter, yellow fluorescence is excluded from detection when the CFP filter set is used. It should be noted that some signal from enhanced green fluorescent protein may be detected with this filter set, and therefore that fluorochrome is not a good candidate for dual labeling with the cyan protein variant. The CFP filter combination is recommended when studying the following fluorophores: ACMA, acridine homodimer, Astrazon Yellow, Atabrine, catecholamine, CFP, Chromomycin A, Genacryl Brilliant Yellow, Genacryl Yellow, Sevron Yellow, SYTO 42 (and 43, 44, 45), and SYTOX Blue. The images presented in Figure 2 demonstrate the performance of this filter combination with a variety of blue-violet-absorbing fluorescence probes targeted at different intracellular locations.

The high-performance Nikon CFP (cyan fluorescent protein) filter combination differs from the other three complements in the blue-violet group by employing a bandpass emission filter, whose 40-nanometer passband (460-500 nanometers) restricts detection to fluorochromes emitting in the cyan-blue spectral region. Ultraviolet, visible, and near-infrared transmission spectral profiles for this filter set are illustrated below in Figure 1. A narrow 20-nanometer excitation passband minimizes autofluorescence and is intended to avoid excitation of certain fluorochromes commonly utilized for dual labeling experiments in conjunction with cyan fluorescent protein. Although primarily designed for imaging of fluorescent proteins, this bandpass emission combination is useful for obtaining images of specimens having multiple labels when one of the fluorophores is efficiently excited in the blue-violet spectral region.

Cyan fluorescent proteinexcitation emission

Abramowitz, Alan I. 2015. The New American Electorate: Partisan, Sorted and Polarized. In James Thurber, ed., American Gridlock: The Sources, Character and Impact of Political Polarization. New York: Cambridge University Press.

According to Palonen, polarization solves the initial problem of fragmentation, lack of unity, by instituting a frontier that sustains two communities as a bipolar hegemony. It requires constant rearticulation and, therefore, constant antagonism on that frontier… “Similar to the one-party system or consensus, polarization and bipolar hegemony bracket out less important demands and maintain an illusion of unity, rejecting anything that might shake internal cohesion,” she underlines.

Alan Abramowitz and Jennifer McCoy, “United States: Racial Resentment, Negative Partisanship and Polarization in Trump’s America,” in Annals of American Academy of Political and Social Sciences, 681:1(January 2019): 137-156.

J. Tucker, A. Guess, P. Barbera, C. Vaccari, A. Siegel, S. Sanovich, D. Stukal, B. Nyhan (2018). Social Media, Political Polarization, and Political Disinformation: A Review of the Scientific Literature, commissioned by the Hewlett Foundation.

Abramowitz, Alan I. and Walter J. Stone. 2006. The Bush Effect: Polarization, Turnout, and Activism in the 2004 Presidential Election. Presidential Studies Quarterly, 36: 141-154.

Press-party parallelism and polarization of news media during an election campaign: The case of the 2011 Turkish elections — A Çarkoğlu, L Baruh, K Yıldırım, The International Journal of Press/Politics, 2014, 19 (3), 295-317.

Firat, Rengin B. and Pascal Boyer. 2015. “Coalitional Affiliation as a Missing Link Between Ethnic Polarization and Well-being: An Empirical Test from the European Social Survey.” Social Science Research, Vol. 53, pg. 148-161.

Abramowitz, Alan I. 2010. The Disappearing Center: Engaged Citizens, Polarization and American Democracy. New Haven: Yale University Press.

Castanho Silva, Bruno. (2017). Populist radical right parties and mass polarization in the Netherlands. European Political Science Review. 10. 1-26. 10.1017/S1755773917000066.

Fluorescence emission intensity from a culture of rat kangaroo kidney epithelial cells (PtK2 line) that were immunofluorescently labeled with primary anti-cytokeratin (an intermediate filament protein) mouse monoclonal antibodies followed by goat anti-mouse Fab fragments conjugated to Marina Blue.

Alban Lauka, Jennifer McCoy and Rengin B. Firat. “Mass Partisan Polarization: Measuring a Relational Concept” in Special Issue on Polarization and Democracy: A Janus-faced Relationship with Pernicious Consequences, American Behavioral Scientist, 62:1 (January 2018): 107-126.

Yellowfluorescent proteinexcitation emission

Jennifer McCoy and Murat Somer, “Toward a Theory of Pernicious Polarization and How it Harms Democracy: Comparative Evidence and Possible Remedies,” in Annals of American Academy of Political and Social Sciences, 681, no. 1 (January 2019): 234-271.

Somer, Murat, and Jennifer McCoy. “Transformations through Polarizations and Global Threats to Democracy.” The ANNALS of the American Academy of Political and Social Science 681, no. 1 (January, 2019): 8–22.

Fluorescence emission intensity from a culture of bovine pulmonary artery endothelial cells stained with DAPI, which targets DNA in the cell nucleus.

On the other hand, a World Bank report shows that many countries in Europe and Central Asia (ECA) are witnessing significant political polarization. Increasing numbers of voters appear to be moving away from centrist positions, abandoning long-held political commitments, and losing faith in established parties and to some extent institutions… Many issues — including economic difficulties, ethnic rivalries, the refugee crisis, and geopolitical tensions — may be driving political polarization in ECA. The importance of each varies by country. There does appear to have been some shift across ECA away from traditional, more centrist political parties, as well as toward more populist political opinions, since the beginning of this century.

“Alternatively, one of the main parties is seen as a populist. In Hungary there are two,” reminds Palonen and adds that “Populism is a hegemonic formation. They profess black-and-white rhetoric on the people and the elite, the tendential empty stances on values and policies and a stark confrontation with the political adversary. Post-Communist politics in Hungary are politics of a bipolar hegemony and competing populism. A ‘hegemonic formation’ fixes a maximum amount of meanings together or blocks them out of it. In the political rhetoric identities, symbols and history carry meanings for the two poles. The two camps of the bipolar hegemony sustain themselves through their opposition to one another rather than through their content. Polarization can be seen as a system of dual consensus, reproducing the typical problems of consensus.”

Anna Scordato and Stanley Schwartz - Bioscience Department, Nikon Instruments, Inc., 1300 Walt Whitman Road, Melville, New York, 11747.

Abramowitz, Alan I. 2012. American Political Parties in an Age of Polarization. In Mark D. Brewer and L. Sandy Maisel, eds., The Parties Respond: Changes in American Parties and Campaigns, 5th edition. Boulder, CO: Westview Press.

Samuel Handlin, State Crisis in Fragile Democracies: Polarization and Political Regimes in South America. Cambridge University Press, 2017.

Political polarization, according to an article by Emilia Palonen, is a political tool — articulated to demarcate frontiers between ‘us’ and ‘them’ and to stake out communities perceived as moral orders. Palonen writes that “polarization is a situation in which two groups create each other through demarcation of the frontier between them. The dominant political frontier creates a point of identification and confrontation in the political system, where consensus is found only within the political camps themselves.”

Meanwhile, a central claim of Hadlin’s article is that polarizing populism is enabled by state crises. State crises refer to situations characterized by two necessary elements: i) States perform poorly: Basic institutions such as the public administration, the judiciary, and the police prove inefficient and highly corrupt in their conduct and provision of goods and services. ii) Citizens come to possess very little confidence in these basic state institutions and government in general.  However, polarizing populism required not just state crisis but also contextual conditions that induced outsiders to build elite coalitions on the left. The proesses by which populist outsiders build movements, especially the coalitions and alliances they forge, therefore become critical in determining whether populists will adopt pragmatic or polarizing positions, and therefore whether or not they will transform party systems in highly polarizing directions.

Webster, Steven W., and Alan I. Abramowitz. 2017. The Ideological Foundations of Affective Polarization in the U.S. Electorate. American Politics Research 45: 621- 647.

Abramowitz, Alan I., and Kyle L. Saunders. 1997. Party Polarization and Ideological Realignment in the U.S. Electorate, 1976-1994. In L. Sandy Maisel, ed., The Parties Respond, 3rd edition. Boulder, Colorado: Westview Press.

A culture of rat skeletal muscle tissue cells (L6 cell line; myoblasts) were immunofluorescently labeled with primary anti-cdc6 (human) mouse monoclonal antibodies followed by goat anti-mouse Fabfragments conjugated to Marina Blue. Cdc6 is expressed in actively replicating cells to function during eukaryotic replication initiation, and is essential for DNA synthesis.

Presented in Figure 2(a) is the fluorescence emission intensity from a culture of rat thoracic aorta (muscle) cells that were immunofluorescently labeled with primary anti-oxphos complex V inhibitor protein monoclonal antibodies (mouse) followed by goat anti-mouse Fab fragments conjugated to Pacific Blue. The absorption maximum of Pacific Blue is 410 nanometers and the emission maximum occurs at 455 nanometers. In addition, the specimen was simultaneously stained for F-actin with Alexa Fluor 488 (green) conjugated to phalloidin, and for DNA with SYTOX Orange. Note the absence of signal from both the orange and green fluorophores (SYTOX localized in the nucleus would appear green under these observation conditions). In many cases, SYTOX Orange stains a variety of cytoplasmic elements in addition to DNA, although this is not evident in the image.

Hameleers, M., & van der Meer, G. L. A. (2020). Misinformation and polarization in a high-choice media environment: How effective are political fact-checkers? Communication Research, 47, 227-250. https://doi.org/10.1177/0093650218819671

Figure 2(b) demonstrates fluorescence emission from a culture of rat skeletal muscle tissue cells (L6 cell line; myoblasts) that were immunofluorescently labeled with primary anti-bovine alpha-tubulin mouse monoclonal antibodies followed by goat anti-mouse Fab fragments conjugated to Alexa Fluor 430. The absorption maximum of Alexa Fluor 430 is 431 nanometers and the emission maximum occurs at 541 nanometers. Although the intracellular microtubule network is heavily stained using this protocol, the bandpass filter in the CFP combination does not pass a large amount of fluorescence emission from Alexa Fluor 430, and produces only a weak signal that is concentrated near the nucleus. In addition, the specimen was simultaneously stained for F-actin with Alexa Fluor 488 conjugated to phalloidin, and for mitochondria with MitoTracker Red CMXRos. Note the absence of signal from the red (MitoTracker) and green (Alexa Fluor 488) fluorophores.

Gulbrandsen, Trygve Jens & Hoffmann-Lange, Ursula (2007). Consensus or polarization? Business and Labour Elites in Germany and Norway, In Fredrik Engelstad & Trygve Jens Gulbrandsen (ed.), Comparative Studies of Social and Political Elites. Elsevier. ISBN 978-0-7623-1379-2.

Political polarization can refer to the divergence of political attitudes to ideological extremes. Almost all discussions of polarization in political science consider polarization in the context of political parties and democratic systems of government. In most two-party systems, political polarization embodies the tension of its binary political ideologies and partisan identities.

Yang, J., Rojas, H., Wojcieszak, M., et al. (2016). Why are “others” so polarized? Perceived political polarization and media use in 10 countries. Journal of Computer-Mediated Communication, 21(5), 349- 367.

Abramowitz, Alan I. 2012. Grand Old Tea Party: Partisan Polarization and the Rise of the Tea Party Movement. In Lawrence Rosenthal and Christine Trost, eds., Steep: The Precipitous Rise of the Tea Party. Berkeley: University of California Press.

John D. Griffin, Nathan S. Claxton, Matthew J. Parry-Hill, Thomas J. Fellers, Kimberly M. Vogt, Ian D. Johnson, Shannon H. Neaves, Omar Alvarado, Lionel Parsons, Jr., Michael A. Sodders, Richard L. Ludlow, and Michael W. Davidson - National High Magnetic Field Laboratory, 1800 East Paul Dirac Dr., The Florida State University, Tallahassee, Florida, 32310.

Tucker, Joshua & Guess, Andrew & Barbera, Pablo & Vaccari, Cristian & Siegel, Alexandra & Sanovich, Sergey & Stukal, Denis & Nyhan, Brendan. (2018). Social Media, Political Polarization, and Political Disinformation: A Review of the Scientific Literature. SSRN Electronic Journal. 10.2139/ssrn.3144139.