Ronald Kroeze
email: d.b.r.kroeze@vu.nl

Pol Dalmau
email: pol.dalmau@upf.edu

Frédéric Monier
email: frederic.monier@univ-avignon.fr

Introduction: Corruption, Empire and Colonialism in the Modern Era: Towards a Global Perspective

Scandal, corruption, exploitation and abuse of power have been linked to the history of modern empire-building. Colonial territories often became promised lands where individuals sought to make quick fortunes, sometimes in collaboration with the local population but more often at the expense of them.

discourses in parliaments and the press, and leading to reforms in colonial administrations. In spite of some valuable case studies and general essays on corruption and imperialism, historians have usually paid little systematic attention to these questions. This is not to say that colonial corruption is an overall neglected topic. The literature on colonialism refers to the issue of corruption as an element of colonial rule and the colonial economy. [START_REF]For example, for the Dutch-Indonesian case Jan Luiten van Zanden and Daan Marks pointed to corruption and other "extractive institutions[END_REF] Such studies reveal the recurrent and sometimes systematic existence of corruption in a colonial context, and how varied it is defined and understood in different studies. There is also a series of contributions dedicated to case studies of corruption in a colonial setting. Examples are studies of the Warren Hastings scandal or corruption in colonial Burma (present-day Myanmar) and colonial Nigeria for the British case, as well as the role of corruption with regard to French Algeria, the Spanish Philippines or the decline of the Dutch East India Company. [START_REF] Nicholas | The Scandal of Empire. India and the Creation of Imperial Britain[END_REF] Moreover, important studies on the history of empire often mention corruption, for example, as one of the reasons for the fall or reform of certain imperial regimes. [START_REF] Bayly | of difference"; Burbank and Cooper also, every now and then, point at the role of corruption in the history of empires as shown in Jane Burbank and Frederick Cooper, Empires in World History. Power and the Politics of Difference[END_REF] These accounts provide valuable insights as they point at the role of misuse of power and resources as part of the "politics of difference" of imperial rule, but barely reflect more in depth on the links between colonialism and corruption. In other words, corruption is treated more as a symptom (whether in colonial governance, the economy or the characteristics of an empire) than as a specific subject of enquiry.

Recent years have also seen a series of new publications on the history of corruption in Europe. These studies have shown that corruption as an idea and discourse, as well as a practice, played an important role in the history of modern politics and state-building processes. These works have highlighted the complexity of corruption in the modern era, for example, that corrupt practices continued to exist even though "modern" elites proclaimed they had freed their regimes from them. Moreover, in the late eighteenth and nineteenth centuries, accusations and debates about corruption served to initiate reform or, simply, as a pretext to undermine old structures and representatives of the so-called "Ancien Régime". [START_REF]Dénoncer la corruption. Chevaliers blancs, pamphlétaires et promoteurs de la transaprence à l'époque contemporaine[END_REF] Therefore, anticorruption campaigns could and were also used as political weapons, to get rid of opponents and to promote politicised institutional reforms. [START_REF] Ivo | Corruption and Anticorruption in the Era of Modernity and Beyond[END_REF] Additionally, several historians have argued that the understanding of corruption as well as the link between corruption and political reform entered a new phase somewhere towards the end of the eighteenth century. From that moment onwards, instead of simply being a word to be used for a great variety of deviations (sexual, moral, religious, administrative), corruption became more often defined in political terms as the misuse of public office or the general interest for private gain. Moreover, it became an absolutely non-tolerable phenomenon in the public arena. This does not mean, of course, that corruption ceased to exist; rather, corruption became a more serious and challenging problem in terms of political legitimacy. 6 As a result, a new political discourse developed in which corruption was portrayed as a remnant of "traditional" societies-in which "Ancien Régime" practices such as patronage and clientelism were rampant-that could be eliminated if the appropriate "modern" reforms were adopted.

Although, there is still debate among historians about how sharp the break with the past really was 7 -see also the contribution to this volume by Jens Ivo Engels and Frédéric Monier-these insights that have been framed in the context of European history can bring valuable perspectives to the history of colonialism and empire. For example, it can help us to locate the development and consequences of the idea that corruption was a problem of traditional regimes and that it belonged to a geographical "Other": the colony and its local culture and inhabitants. This argument was used by European colonial elites in the nineteenth and early-twentieth centuries to justify colonial rule: it was legitimate as it would end corruption and bring modernity, so it was argued. Indeed, if corruption had already been present in the Enlightenment's idea of "Oriental despotism", it now became part of the civilising discourse of nineteenth-century European colonialism. 8 As such, the study of colonial corruption allows the tackling of historiographical debates about the ideological fundaments of civilising discourses, modernisation programs and the legitimacy of colonial rule, which is an important theme in the history of colonialism (as well as in postcolonial and decolonisation studies, too). 9 Methodologically, this volume takes inspiration from the latest stream of publications about the history of corruption as well. These studies have underlined the importance of a contextual approach that understands corruption, not as something fixed and universal. Indeed, corruption is by its very (linguistic) meaning, disapproved as an immoral phenomenon, and corruption in modern history is often about a form of misuse of public resources for private or group gain, but the real meaning of "immoral", "misuse", "public resources" and "private gain", differs over time and place. One needs to analyse specific cases, scandals and debates, to understand corruption more precisely. This approach has proved highly valuable and has opened up new lines of research. In countries such as Germany, France and the Netherlands, scholars have devoted growing attention to a topic that had little tradition in the respective national historiographies. 10 In other cases, such as those of Southern Europe and Latin America, traditional narratives that linked corruption with backwardness in historical development have been replaced by new research questions and methods. Examples of these are the interest to trace the changing meanings of corruption in periods of transition, the eruption of scandals in the public sphere or the measures to curtail corruption practices. 11 The outcome of these new publications has been a renewed and thriving historiography that has benefitted from the creation of new international collaborative research teams. While these developments have decisively contributed to renewing the field, to the point that we can speak of a "new history of corruption", the nation-state has remained the predominant framework of reference. Moreover, most research questions have been posed from a European perspective.

This book is a first attempt, instead of a final analysis, to discuss the topic of corruption, empire and colonialism in a systematic manner and from a global comparative perspective. It does so through a set of original studies that examines the multi-layered nature of corruption in four different empires (Great Britain, Spain, the Netherlands and France) and their possessions in Asia, the Caribbean, Latin America and Africa. Readers interested in colonialism will find in this book a wide array of studies that examine the changing contours of corruption and the different responses that empires designed to confront it. Against the temptation of seeing colonial rule as being permanent and stable, corruption sheds light on periods of crisis and reform, pointing at crucial moments when imperial rule was called into question or redesigned. Corruption can thus be seen as an important characteristic of colonial rule as well as a catalyst for reform in the modern era, a phenomenon that illuminates the strategies that empires put forward in order to cope with historical change. In parallel to this, the emphasis on the links between colony and metropolis allows for opening up new perspectives of analysis in a traditionally state-driven historiography, and to unveil new spatial units of analysis, such as Atlantic and-above all-global history that have not yet been applied to the history of corruption.

Coherence and Approach

The volume offers a variety of case studies, touching on the history of four different empires and their possessions in Asia, Africa, the Caribbean and Latin America. Coherence is provided, first of all, by the overall contextual approach of corruption-a method that has been applied in the most recent historiography on the topic, as discussed above. A contextual approach is important to find out the precise meanings: corruption has to be examined and explained through the very specific times and places where it was debated. Thus, the volume discusses examples of corruption and debates about how they were understood within the different time frames and geographical colonial settings of the moment, providing a variety of understandings of the roles corruption played. As will become clear, at times corruption was mainly about immoral forms of economic exploitation, while in other circumstances illegitimate forms of political or cultural dominance were at the heart of scandals and debates.

Second, coherence is provided by an overarching global comparative approach. Such standing is informed by the general literature on the history of empires from a global perspective, 12 including the books already published in the same book series as this volume. 13 Although there are many and not always coinciding understandings of global history, it can generally be defined on the basis of three elements. A global perspective seeks to explain the complexity of historical phenomena through the comparison between different parts of the world, but is also compatible with the interest to highlight the interconnections between these parts. This approach does not necessarily seek to write a "total history" of the whole planet, nor to merge all historical accounts into one single metanarrative. Rather, it seeks to break with the separate compartments that have traditionally characterised the writing of history by emphasising the similarities and the differences between diverse territories, cultures and societies, as well as by illuminating the connections that intertwined them. 14 A second aim of using a global history perspective is to challenge "traditional and sometimes obsolete national narratives". 15 In the field of corruption, one could think of narratives that recurrently present corruption as being particularly present in certain empires (such as the "backward" Spanish, Portuguese and Ottoman empires), while supposedly being less present in other ones. Often, however, the historical situation was more complicated-corruption was a phenomenon present in all empires, but manifested and changed across time in many different forms. Moreover, scholars in the past-including historians-helped to construct these stereotypical images and "black legends" for political, imperial and nationalist reasons. 16 A third related fundamental aim in the writing of global history is to challenge Western-centred master narratives by adding a new plurality of voices, sources and subaltern actors into historical analysis. 17 In practical terms, these theoretical assumptions and aims informed the authors of this volume to understand corruption as a problem inherent to the history of all empires, instead of a problem specific to supposedly "Southern", decrepit or decaying ones. Indeed, the four empires covered in this book (British, French, Spanish and Dutch) possessed a long experience of colonial rule, which in some cases stretched back to early modern times. When corruption was perceived as a recurring or systemic problem, it often led to moments of crisis and political conflict, that resulted in debates in the public sphere about normative values and the necessity of reform. On some occasions, the outcome was the implementation of legal and political programs that sought to re-design the foundations of empire, both in terms of legitimacy and practical rule. In some other cases, however, corruption served as a powerful pretext to justify the need to "civilise" indigenous societies, as Nicholas B. Dirks has shown for the case of the British empire. 18 The study of corruption thus brings dynamism to the history of empire, stressing contingency and change, while contributing to explain why they have been one of the most enduring political entities in world history. Taken together, the four empires covered in this book, alongside the colonies they possessed in Africa, Asia and the Caribbean, reveal how pervasive corruption was at the time, in addition to how different it was depending on where and when it took place. The focus on a wide number of cases allows the grappling of these two dimensions that are inherent to corruption. Namely, its universality as a problem common to all empires, as well as its complexity as a multi-layered phenomenon that was time and place dependent. Only a comparison between empires can serve as a safeguard against simplistic generalisations, which take a handful cases to draw shallow (and often ahistorical) conclusions, 19 and at the same time move beyond the exceptionalism of nation-centred approaches. For these reasons, all of the authors in this book emphasise transnational connections. Additionally, they make an effort to place their own case study and research questions in relation to other ones. Furthermore, although of course more sources and perspectives could have been included, the outcome is-as we hope-a cohesive volume with cross-references in each chapter that challenge nation-centred approaches, and which when taken together provide a global outlook. 20

Structure of the Volume

Although the chapters represent differences in approach that are mainly the result of the fact that the authors come from different fields and historiographical traditions, they all subscribe to the benefits of (a) challenging the European nation-state as the traditional frame to research the history of corruption; (b) a methodological approach that is characterised by a contextual understanding of corruption and (c) cross-referencing by linking different colonial settings in order to provide a global perspective.

In total, the volume consists of eleven chapters-and a concluding chapter at the end-that are ordered more or less chronologically, focusing on a period that covers the end of the eighteenth century up to the beginning of the twentieth century. This period in history, famously referred to as the "birth of the modern world", was an era in which large empires were formed and cemented, and where new ideas of human development (such as those about civilisation and progress) were developed and used to legitimise the hierarchical subordination of races and cultures across the globe. 21 In practice, however, the purpose of bringing "civilisation" to the new colonies often proved to be a much more difficult goal to achieve. Imperial powers did not only have to impose their control over immense extensions of territory, but also faced the challenge of subjecting widely heterogeneous populations. Furthermore, in such attempts they had to rely on a very limited number of imperial agents that on repeated occasions took advantage of their position, and of their distance from the metropolis, to make illicit gains. Cases of corruption, and how they were debated and managed both in the colony and the metropolis, therefore allow the examination of the forms of governance and tensions that were at the core of imperial rule. Informed by this and by the earlier introduced historiographical trends, we have structured the contributions to this book in two parts.

The contributions of Part I-Corruption and Narratives of Imperial Decline and Reform During the Age of Revolutions, c. 1800-discuss corruption as a problem for all empires in the decades around 1800, which was a period of global revolutions and major reforms. Contemporaries of the last decades of the eighteenth and first decades of the nineteenth centuries era often saw colonial corruption as a major reason for the declining power or economic failure of "their" empires, as was clearly apparent in the debates about the decline of the Spanish and the Dutch Republican VOC-empire. This discourse, however, was also very present in the case of the British and French empires. Colonial scandals and debates about corruption in the colony served to criticise the old regime and to initiate change in persons and structures. The historian Lauren Benton, for instance, has recently highlighted the importance that the scandals of this period had in reshaping the legal fundaments of the British empire. 22 Reflecting on the role of corruption in these empires from different geographical perspectives, therefore, appears as an untapped subject. Additionally, there is the need to re-examine the role that corruption played in the creation of national stereotypes (e.g. "Black Legends" in the Spanish case), attributing to a stereotypical image of decaying corrupt empires and reforming modern empires.

The contributions of Part II-Civilising Missions and "Oriental" Corruption During the Age of Modern Imperialism, c. 1900-focus on corruption in the decades around 1900, a period of extending the spheres of state power in different regions a process that was justified by the "civilising discourses". Cultural and moral arguments were central elements in justifying the seizure of new lands and the extraction of resources. 23 Several contributions show that corruption was a recurring element in the genesis, or in the reshaping, of civilising discourses around the year 1900. In some occasions, it was the supposed corrupt nature of indigenous peoples that featured prominently behind the ideologies of modern imperialism, while in others it was the shady dealings of colonial bureaucrats and modern entrepreneurs that justified the need for new ethical fundaments in ruling the colonies. The recurring and multifaceted presence of corruption in civilising discourses and in debates on the colonies, and their roles in reinforcing notions of "bringing modernity" and processes of "Otherness", are dimensions that the different chapters address as well.

I. Corruption and Narratives of Imperial Decline and Reform During the Age of Revolutions, c. 1800

More precisely, Part I comprises five chapters focusing on corruption and narratives of imperial decline and reform during the Age of Revolutions. In this age, corruption was understood as a problem concerning how overseas trade, imperial politics and economics worked. It was also the period of the birth of a more modern concept of corruption, with an emphasis on understanding corruption as a problem of the mixing up of the public and the private, politics and economics, individual and general interests. According to the modern ideal, these should be separated as much as possible. The contributions of this part deal with corruption caused by tensions between these sectors, as well as the narratives about declining old empires and the necessity of reform. Informed by these issues, Bartolomé Yun-Casalilla provides a long-term perspective by looking at the role of corruption in early modern empires. In contrast to traditional narratives that portrayed Iberian empires as obsolete entities that were particularly prone to corruption, he shows that the reality was far more complex. Next to the study of formal institutions, Yun-Casalilla emphasises the need to focus on informal institutions (such as the family and kinship relations), the role of space and the negotiated nature of power, in order to understand a phenomenon that was not yet referred to as "corruption" at the time. All of these reflections illuminate the long history of corruption in the colonies and serve as a valuable reminder against teleological narratives that view the fight against corruption as a sign of modernity.

Chapter 3 by Tanja Bührer, examines the impeachment of the first Governor General of the British East India Company, Warren Hastings, in February 1788. This contribution aims to explain why, disregarding a long-standing argument against "old corruption" in domestic administration and politics, a case of colonial corruption became the most spectacular public scandal in this crucial period of transition from premodern to modern times. For a better understanding of the empire's return home in scandal's guise, a multi-perspective approach of the customary separated fields of national and imperial history, as well as area studies, is applied. Bührer provides an entangled history of the British and French "Imperial Nation-States" and the South Indian "Princely State" Hyderabad. She argues that the specific metropolitan anxieties regarding colonial corruption were caused by its emergence from Anglo-Indian cross-cultural and Anglo-French inter-imperial interactions on the margins of the empire. These "alien" influences sharpened the awareness of presumably national concepts of good governance back home, and caused anticorruption interventions that went ahead of the domestic reforms.

In chapter 4, Anubha Anushree discusses attempts to regulate corruption by the British East India Company. She argues that by the beginning of the second decade of the nineteenth century, the East India Company started projecting corruption as an anomalous and temporary phenomenon that allowed it to formulate a collective and systemic paternal morality. The chapter first focuses on two crucial interlocutors of the first half of the nineteenth century-Thomas Babington Macaulay and William Bentinck-to situate the correspondence between an ascendant governmental moralism and corruption. She then continues by examining several understudied instances of corruption-namely, the cases of Thomas Metcalfe, Mordaunt Ricketts and Edward Colebrook-in order to examine how the early-nineteenth-century discourse of colonial corruption was constituted by a double strategy. On the one hand, corruption came to be increasingly "investigated" and re-described as a financial disorder, whereby the British were presented as "supine" and "passive". On the other hand, the investigations often sought to incriminate Indians and their relationships with these officers. The focus on finances and Indians allowed the British to contain the discourse of corruption, even as the term expanded to discipline a variety of official and quasi-official relationships between the British and the Indians that did not fit the normative character of the nineteenth-century public office.

Chapter 5 by Moisés Prieto, discusses America's "second discovery" in the early-nineteenth century. Inspired by Alexander von Humboldt, merchants, travellers, scientists and adventurers travelled through Latin America with different purposes. Their documents were not only supposed to provide mere entertainment or knowledge about local customs, flora and fauna, but contained historical essays on the recent past of those former colonies as well. Nepotism, favouritism, misappropriation, bribery and arbitrariness were witnessed by those travellers who tried to explain these phenomena in different ways. Prieto argues that colonial corruption should be understood in relation to the history of colonial rule-the distance from the motherland offered opportunities-although officeholders' passions, vices and pursuits of prestige were as important. After emancipation, the second aspect remained but understandings of corruption were further influenced by a new rationalistic view, typical for the Enlightenment and positivism that linked the absence of corruption to (an idea of) progress and vice versa.

In chapter 6, Mark Knights and Zak Leonard discuss two nineteenthcentury cases in the Gujarati princely state of Baroda that shed light on the politics of corruption. The first, running from the mid-1830s to mid-1850s, centred on allegations about the corrupt influence (known as "khutput") of a native clique on the East Indian Company hierarchy; the second, in 1893-1895, turned on allegations against Vasudev Sadashew Bapat, an allegedly corrupt official in a department dealing with sensitive land revenue issues. The authors show that the responses by the British authorities were different in the two cases. In the first, the Bombay hierarchy proved very resistant to challenging khutput despite the vigorous investigatory efforts of one of its own officials, James Outram. In the second, the British authorities were keen to intervene and brought the matter to trial. These differing approaches were nevertheless united by a common desire to maintain maximum influence over the nominally independent state.

II. Civilising Missions and "Oriental" Corruption

During the Age of Modern Imperialism, c. 1900

Continuing the reflection on cases of colonial corruption in the decades around 1800 that are discussed in Part I, the six contributions of Part II shift their perspectives to the last decades of the nineteenth and first decades of the twentieth centuries-the era of modern imperialism and the civilising missions. Ronald Kroeze relates debates of around 1800 to those of around 1900. Kroeze takes the Dutch-Indonesian histories of colonial state formation as a common base to define and test several hypotheses that are informed by debates in the historiography of corruption and (post-)colonialism. One is that corruption is never a neutral objective term and that when it is used in a colonial context it serves to set or challenge norms that underlay colonial power structures. Indeed, the Dutch-Indonesian case shows evidence of the link between corruption and the context of establishing a colonial empire: by both invoking scandals and asking for reform, as well as neglecting or denying corruption in other instances, elites (re)formulated norms in order to set or maintain power structures of colonial state-formation and economic exploitation. Kroeze also argues that cases of colonial corruption show how the metropole and colony were interlinked and influenced each other. For instance, political changes in the metropole, such as the growing influence of more morally outspoken Protestant and Liberal politicians, as well as experiences of misuse in the colony, together caused the emergence of the Dutch equivalent of the civilising mission: the "Ethical Policy". Despite these connections, corruption and moral campaigns against it, often served to strengthen already existing differences and dissimilarities.

Part II then continues with chapter 8, in which Didier Guignard focuses on a specific case of colonial corruption in the context of French Algeria: the Bruat case of 1877. He explains how Algerian rural society was exposed to land confiscations during the nineteenth century; the Bruat case shows how public agents and European politicians took advantage of their front-row seat in order to seize land for their own interests or for cronyism. More precisely, this contribution provides a micro-level analysis of the awarding of 100 hectares of land to a civil servant in Low Kabylia during the 1870s. As a member of the upper class in France, the mother of this civil servant played the role of mediator in negotiations with central authorities to "help" them bypassing legal interdictions. The chapter concludes with a reflection on the usefulness of the concept of colonial corruption.

In chapter 9, Pol Dalmau examines the deep-rooted presence of corruption in Spain's most prosperous colony in the Caribbean: Cuba. He shows how the booming economy of this sugar island in the global market ran parallel to a wide range of fraudulent practices that touched virtually all the levels of the colonial administration. Dalmau does not only provide evidence of this, but also argues that colonial corruption had an Atlantic dimension that can only be fully understood by examining the clientelistic networks that spanned the two sides of the Atlantic, and through an analytical approach that examines the metropolis and colony together. Hence, the chapter shows how Cuban elites made use of novels and other methods of political action to denounce corrupt practices back in the metropolis. Authorities in Madrid, however, often turned a deaf ear to these reports and considered that corruption was a minor price to be paid (and quite often, to benefit from) in order to maintain the integrity of the Spanish empire. The analysis of corruption in Cuba is thus used as a platform from which to examine the Atlantic dynamics of imperial rule, as well as the tensions and resistances that pervaded it.

Gemma Rubí, in chapter 10, continues with the topic of corruption in Cuba, but focuses on Victor Balaguer-Spain's Minister of Overseas Affairs in different periods (1871, 1874 and 1886-1888). The fight against corruption carried out by public employees was a constant in the political career of Balaguer. From the Court of Auditors and from the Debt Inspection Commission, he devoted considerable efforts to pursuing it. Upon access to the position of Overseas Affairs' Minister, Balaguer ran into several powerful irregularities practiced by civil servants of the colonial administration in Cuba, which came to be the continuation of those that he had already found during his previous mandates. Rubí's contribution thus draws on the case of a reputed politician, in order to examine the motivations to fight political corruption in the colonies and the measures that were developed in such attempts.

In chapter 11, Jonathan Saha focuses on paperwork as a source of corruption in colonial Myanmar (formerly Burma) around 1900. He argues that the bureaucratic paperwork produced by colonial states was often embroiled in malfeasant practices. Take, for example, the paperwork that was used to regulate fishing in colonial Myanmar from the late-nineteenth century onwards. Certain littoral areas and deltaic waterways were designated as fisheries. Individuals could bid for leases to these fisheries in auctions. In non-leased open fisheries, people had to apply for licenses to fish. In addition, to mitigate against overfishing, licenses were required for the use of nets. However, the prescriptive nature of these documents did not always have the effects that they were intended to have. This chapter argues that by considering paperwork to be a particular type of commodity, we can better understand the prevalence of particular corrupt practices in the colonial context.

Xavier Huetz de Lemps, in the last contribution of Part II, takes contemporary discussions about the colonial roots of today's corruption as a starting point for an analysis of the role of corruption in the Philippines in the decades around 1900. He argues that corruption in post-colonial Philippines is deeply rooted in the long colonial history of the archipelago, but that this is less a matter of showing that corruption is a very ancient local phenomenon and more about understanding the reasons why corrupt practices passed from one political system to the other. During the Spanish period, embezzlement and abuse of power became unremarkable behaviours for Spanish civil servants and their Philippine subordinates. Beginning in 1898, the Americans gradually endowed the colony with modern democratic institutions. Yet, the US imperial contradictions and the skill of the Philippine political elites allowed the corruption to remain and to pervert the new institutions.

The final contribution to this volume is written by Jens Ivo Engels and Frédéric Monier, which should be read more as a reflection and an agenda for further research, than as a summary of each contribution. Engels and Monier challenge the reader by highlighting the role of lasting systems of gifts and patronage, and emphasise the influence of conflicting norms and political changes for the rise (and absences) of debates about colonial corruption in one context, but not in another. They, like other contributors did, stress the point not to treat "colonial corruption" as only about-and taking place in-the colony.

Notes

INTRODUCTION: CORRUPTION, EMPIRE …

R. KROEZE ET AL.

R. KROEZE ET AL.

et corruption politique à l'époque contemporaine (XIXe-XXe siècles), eds. Frédéric Monier and Jens Ivo Engels (Paris: Armand Colin, 2014), 31-50. 6. See Jens Ivo Engels, Die Geschichte der Korruption. Von der Frühen Neuzeit bis ins 20. Jahrhundert (Frankfurt: S. Fischer, 2014). 7. See Ronald Kroeze, Vitoria, Geltner, "Introduction: Debating Corruption and Anticorruption in History," in Anticorruption in History. From Antiquity to the Modern Era, eds. Ronald Kroeze, André Vitoria and Guy Geltner (Oxford: Oxford University Press 2018), 1-17. 8. On the Enlightenment and the notion of "Oriental" despotism, see: Joan Pau-Rubiés, "Oriental Despotism and European Orientalism: Botero to Montesquieu," Journal of Early Modern History 9, nos. 1-2 (January 2005): 109-190. 9. For an example of a study that examines the role of colonialism, decolonisation processes and "modernity", see Frederick Cooper, Colonialism in Question: Theory, Knowledge, History (Berkeley: University of California Press, 2005). On the language of civilisation, see: Brett Bowden, The Empire ofcivilisation: The Evolution of an Imperial Idea (Chicago: University of Chicago Press, 2009); Martti Koskenniemi, The Gentle Civiliser of Nations. The Rise and Fall of International Law, 1870-1960 (Cambridge: Cambridge University Press, 2009). 10. Examples include: Kroeze, Vitoria and Geltner, Anticorruption in History; Engels, Die Geschichte der Korruption; F. Monier, O. Dard and A. Fahrmeir, eds., Scandales et Corruption. 11. Christopher Rosenmüller and Stephan Ruderer, eds., Dádivas, dones y dineros. Aportes a una nueva historia de la corrupción en América Latina desde el Imperio español a la modernidad (Madrid: Iberoamericana Verveurt, 2016); Borja de Riquer, Joan Lluís Pérez Francesc, Gemma Rubí, Lluís Ferran Toledano and Oriol Luján, eds., La corrupción política en la España contemporánea. Un enfoque interdisciplinar (Barcelona: Marcial Pons, 2018); Pol Dalmau and Isabel Burdiel, eds., La imagen pública del poder. Escándalos y causas célebres en Europa (siglos XIX-XX), Historia y Política, 39, 2018 (special issue). 12. John Darwin, After Tamerlane: the Rise and Fall of Global Empires, 1400-2000 (New York: Bloomsbury, 2008); Jane Burbank and Frederick Cooper, Empires in World History. Power and the Politics of Difference (Princeton: Princeton University Press, 2010); Peter Crooks and Timothy Parsons, eds., Empires and Bureaucracy in World History: From the Late Antiquity to the Twentieth Century (Cambridge: Cambridge University Press, 2016). 13. Manuel Pérez Garcia and Lucio De Sousa, eds., Global History and New Polycentric Approaches: Europe, Asia and the Americas in a World Network System (Singapore: Palgrave Macmillan, 2018); Bartolomé Yun-Casalilla, 16 R. KROEZE ET AL. Iberian World Empires and the Globalization of Europe, 1415-1668 (Singapore: Palgrave Macmillan, 2019). 14. Bayly, The Birth of the Modern World, 1; Sebastian Conrad, What Is Global History? (Princeton, NJ: Princeton University Press, 2016), 67-70; Richard Drayton and David Motadel, "Discussion: The Futures of Global History," Journal of Global History 13, no. 1 (March 2018): 3. 15. Manuel Pérez García, "Introduction: Current Challenges of Global History in East Asian Historiographies," in Global History and New Polycentric Approaches: Europe, Asia and the Americas in a World Network System, eds. Manuel Pérez García and Lucio De Sousa (Singapore: Palgrave Macmillan, 2018), 2; Jorge Luengo and Pol Dalmau, "Writing Spanish History in the Global Age," Journal of Global History 13, no. 3 (November 2018): 425-445. 16. For the case of the Spanish Empire, see: Richard Kagan, "Prescott's Paradigm: American Historical Scholarship and the decline of Spain," American Historical Review 101, no. 2 (April 1996): 423-46; For that of the Ottoman, Aslı Çırakman, From the "Terror of the World" to the "Sick Man of Europe". European Images of the Ottoman Empire and Society from the Sixteenth Century to the Nineteenth (New York: Peter Lang, 2002). 17. Dipesh Chakrabarty, Provincializing Europe. Postcolonial Thought and Historical Difference (Princeton: Princeton University Press, 2000); Dominic Sachsenmaier, "Global History and Critiques of Western Perspectives," Comparative Education 42, no. 3 (August 2006): 451-470. 18. Dirks, Scandal of Empire. 19. Alan L. Karras, Smuggling. Contraband and Corruption in World History (Lanham: Rowman & Littlefield Publishers, 2010). 20. Sven Beckert and Dominic Sachsenmaier, eds., Global History, Globally: Research and Practice Around the World (London: Bloomsbury Academic, 2018). 21. Bayly, The Birth of the Modern World; Thomas McCarthy, Race, Empire and the Idea of Human Development (New York: Cambridge University Press, 2009). 22. Lauren Benton, Rage for Order. The British Empire and the Origins of International Law, 1800-1850 (Cambridge: Harvard University Press, 2016). 23. McCarthy, Race, Empire and the Idea; Martin Thomas and Richard Toye, Arguing about Empire: Imperial Rhetoric in Britain and France, 1882-1956 (Oxford: Oxford University Press, 2017).

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P M Ajith
email: ajith.pm@kau.in

C R Rini

Comparison of Hydroponic and Conventional Grafting Techniques in Black Pepper (Piper nigrum L.)

Keywords: Black pepper, graft, soil-less, Piper colubrinum, hydroponic

The most devastating disease affecting black pepper (Piper nigrum L.) is Phytophthora foot rot against which none of the varieties is resistant. This difficulty has been overcome by the horticultural technique of grafting P. nigrum on the resistant root stock viz. P. colubrinum-a marshy wild relative of black pepper .The conventional technique of grafting P. nigrum on P. colubrinum takes nine months to one year for developing a graft ready to be planted in the field and is labour and irrigation intensive. Hydroponic soil-less methods based on the marshy adaptation of P.colubrinum and which require lesser labour and water have been explored to address the issues with the conventional method. An experiment in complete randomised design with five grafting methods and six replications was conducted at Pepper Research Station, Panniyoor,Kannur, Kerala, India during 2019-20 to compare the conventional grafting technique with hydroponic techniques. Instant grafting of the scion portion on the non -rooted root stock portion and rooting of the root stock hydroponically once the grafting procedure is completed has been found to produce field ready grafts in 95 days with the lowest graft loss of 6.8 per cent and water use efficiency of 117.7 per cent.

INTRODUCTION

Black pepper (Piper nigrum L.), the historic 'King of Spices' has been used as spice since 4 th century B.C. [START_REF] Jibat | Characterization of Phytophthora capsici foot rot disease of black pepper in Ethiopia[END_REF]. The most devastating disease affecting black pepper is Phytophthora foot rot against which no variety has been found to be resistant [START_REF] Hao | De novo transcriptome sequencing of black pepper (Piper nigrum L.) and an analysis of genes involved in phenylpropanoid metabolism in response to Phytophthora capsici[END_REF]. This difficulty has been overcome by the horticultural technique of grafting P. nigrum on root stocks of the wild related marshy species Piper colubrinum L. which is resistant not only to Phytophthora but also to nematodes causing root knot in black pepper [START_REF] Krishnamoorthy | Improvement of black pepper[END_REF]. The technique of grafting of P. nigrum on P. colubrinum has been very successful and has been well standardized and well known [START_REF] Vanaja | Graft recovery of Piper nigrum L. runner shoots on Piper colubrinum Link. root stocks as influenced by varieties and month of grafting[END_REF]. In the conventional method, two to three node cuttings of P. colubrinum of approximately 15 cm length are planted in poly bags of appropriate size to get them rooted. It takes approximately six to nine months for the cuttings of P. colubrinum to get rooted properly and reach a height of around 65 cm and appropriate girth of around 1 cm diameter at 45 cm height where cleft grafting is done in the popular method (Fig. 1). Grafting at a height of around 50 cm is inevitable to avoid splashing of soil and debris that contain spores of Phytophthora and also to get more aerial roots growing from the root stock to the ground [START_REF] Krishnamoorthy | Improvement of black pepper[END_REF].

Once grafting is completed, it takes another three months for the grafts to grow well with 5-6 well developed leaves so that they can be planted in the field. In total, it takes nine months to one year for developing a graft with a graft union height of 45 cm or higher which is ready to be planted in the field. The conventional method is a slow process which requires greater quantities of irrigation water and is labour intensive. It is required to find out faster and efficient alternatives to the conventional method with lesser irrigation water requirement. Besides this, the potting medium in poly bags often harbour pathogenic fungal spores and nematodes which unintentionally invade farmers' fields once these grafts are planted in their field. Transportation of grafted plants is cumbersome and costly due to the bulky nature of potting medium. Adaptation of P.colubrinum to marshy habitat which indicates its ability to root and thrive in water has never been exploited in graft production (Fig. 2). Hence a trial was undertaken to compare the performance of soil-less hydroponic methods of grafting with the conventional and other possible alternatives.

MATERIALS AND METHODS

The trial was undertaken at Pepper Research Station, Panniyoor, Kannur, Kerala, India during 2019-20.The experiment consisted of 5 treatments (Table 1).

The experimental design was completely randomised design (CRD) with 6 replications. Only orthotropic shoots of P. colubrinum were used as root stock and runners (basal adventitious shoots) of P.nigrum variety 'Panniyur 1' were used as scion in the experiment. The size of the poly bags used was 20 cm x 15 cm and potting medium was 1:1:1 mixture of sand, soil and dry farm yard manure. Irrigation water required to bring the potting medium in poly bags to saturation point was calculated as per Imakumbili [START_REF] Imakumbili | Making water stress treatments in pot experiments: An illustrated step-by-step Guide[END_REF]. Two hundred millilitres of water once daily was applied to each poly bag to bring it to saturation. In hydroponic treatments, 500 ml clean tap water was taken in 1 litre containers and only the basal two nodes of the root stock were submerged in water. Water in the container was replaced with fresh tap water once in 10 days. All the treatments were kept in a closed poly house nursery, under natural day light. The temperature inside the poly house seasonally varied from 28 °C to 35 °C and relative humidity varied from 85% to 98%. Data was recorded on days to bud activation on root stock, days to root initiation, number of roots on root stock 60 days after planting/submergence, length of roots on root stock 60 days after planting/submergence (cm), days taken for grafting on root stock, days to get field-ready grafted plants, water requirement per field-ready graft (L), per cent loss of grafted plants and water use efficiency. Days taken for grafting on rootstock was recorded as the number of days taken by P.colubrinum cutting to grow and reach a height of around 65 cm and appropriate girth of around 1 cm diameter at 45 cm height where cleft grafting could be done properly .Grafts with minimum graft union height of 45 cm and with 5-6 well developed leaves on the scion were considered to be ready to be planted in the field. Water requirement per graft was calculated by dividing the total volume of irrigation water applied to the treatments by the number of replications in case of treatments where root stocks were planted in poly bags. Water requirement per graft in case of hydroponic treatments was calculated as the total volume of water to be kept in containers for keeping the

RESULTS AND DISCUSSION

Days to bud activation on root stock ranged from 7.5 to 15 (Table 2).

The earliest bud activation on root stock was recorded for T2 (P. nigrum grafted on 45 cm long P. colubrinum and the root stock put in water) which was on par with T1 and T3 and the last to record bud activation was T5 (P. nigrum grafted on 45 cm long P. colubrinum and planted in poly bag).T2 recorded significant earliness for root initiation on root stock while the last to root was T5 which was on par with T1.Root stocks planted in potting mixture generally took more time for root initiation. The highest number and length of roots 60 days after planting/submergence was recorded for T2 (Figs. 8 and9).This trait can be supposed to impart greater anchorage once planted in soil and greater nutrient absorption ability to T2 during the early months of graft union. Fourty five centimetre long P.colubrinum cutting put in water (T4) became ready for grafting around one month earlier than T1 even though the earliest bud initiation on root stock was observed in T1. This could be attributed to the early root initiation and better root length in T4. Control (T3) took the highest number of days (206.7) for producing sufficient growth for getting 45 cm long root stock. Instant grafting was possible for T2 and T5 only. Bud activation on scion after grafting was the earliest in T2 which was on par with T4.T2 produced field-ready grafted plants in 95 days while T3 (control) took 287.3 days and T4 took 124.2 days. Irrigation water requirement per field-ready graft was the lowest for T2 (4.75L) and the highest for the conventional method (57.46 L).Though instant grafting was possible in T2 and T5, percent loss of grafts was the highest and the most significant in T5.This could be due to the failure of nonrooted root stock to supply water to the scion and consequent wilting of scion. Per cent loss of grafts was the least for T2 (6.8%). [START_REF] George | Grafting studies for production of bush pepper[END_REF] Has reported a maximum per cent survival of 93.33% among Piper species. In general, early bud activation on scion and lesser per cent loss of grafts were observed when the basal nodes of root stocks were put in water rather than anchored in potting mixture. Water use efficiency was the highest for T2 (117.7%) and the least for the conventional method (8.8%).

Soil -less method of grafting P.nigrum on P.colubrinum and keeping the lower nodes of root stock in water was found to produce the highest number of field-ready grafted plants in the minimum time. This method has the additional advantages of high water use efficiency, freedom from daily irrigation and, thus saving irrigation water and labour. Inadequate water availability and labour scarcity have been indicated as two constraints faced by black pepper farmers [START_REF] Krishnamoorthy | Improvement of black pepper[END_REF] and this soil-less grafting method has great relevance under such challenges [START_REF] Imakumbili | Making water stress treatments in pot experiments: An illustrated step-by-step Guide[END_REF].

CONCLUSION

Instant grafting of P. nigrum on P. colubrinum root stock of sufficient length followed by submerging the basal two nodes of the root stock in water was found to produce the highest number of grafts in much shorter time than in the conventional method. This soil-less, water use efficient method also saves irrigation water and labour.

Fig. 1 .Fig. 2 .FigFig. 8 .

 128 Fig. 1. Cleft grafting in P. nigrum

Table 1 . Treatments Sl.No. Treatment Description of treatment

 1

	Figure No.

Table 2 . Growth parameters and recovery of grafts under different systems of grafting in black pepper

 2

	Trea	Days to	Days to	Number of	Length of roots	Days		Days to	Days to	Water	Per cent	Water
	tme	bud	root	roots on root	on root stock	taken	bud	field ready	requirement	loss of	use
	nts	activation	initiatio	stock 60 days	60 days after	for		activation	grafted	per field ready	grafts	efficien
		on root	n	after	planting/subme	grafting	on scion	plants	graft(L)		cy
		stock		planting/subm	rgence(cm)			after					(%)
				ergence				grafting
	T1 T2 T3 T4 T5	7.5 c 9.3 c 9.5 c 11.8 b 15 a	13.7 a 5.7 c 13.3 ab 11.8 b 14.5 a	7.0 a 7.3 a 3.5 c 5.8 b 7.0 a	7.3 c 16.1 a 7.7 c 12.3 b 4.6 d	85.8 b -206.7 49.2 c -	a	17.5 b 12.5 c 17.7 b 13.8 c 19.8 a	184.5 95.0 d 287.3 124.2 -	b a c	36.9 4.75 57.46 6.21 -	22.8(28.6)* b 6.8(14.9) d 15.3(22.9) c 12.2(20.4) c 94.0 (76.4) a	12.6 117.7 8.8 84.8 -
	CD	2.2	1.6	1.1	0.7	12.8		1.9	6		-	3.4	-
	(5%)
	CV	17.5	11.5	14.4	6.3	9.1		10.1	2.9		-	8.9	-

*Figures in parantheses indicate transformed values

ACKNOWLEDGEMENT

The author wishes to acknowledge the help rendered in grafting by Ms. Zuharabi M, Skilled Assistant, Pepper Research Station, Panniyoor, Kannur, India.

COMPETING INTERESTS

Authors have declared that no competing interests exist.


Geoffray Bonnin

Danilo Dessì

Gianni Fenu

Martin Hlosta

Mirko Marras
email: mirko.marras@acm.org

Harald Sack

Guest Editorial of the FGCS Special Issue on Advances in Intelligent Systems for Online Education

Introduction

The education sector is increasingly relying on online learning. Educational and training institutions are being motivated to endorse online learning strategies thanks to its technical, economic, and operational feasibility. This has become even more important after the lockdown caused by the breakout of COVID-19, when even universities revised their educational strategy, moving to online teaching. Learners and teachers are benefiting from the flexibility, accessibility, and costs of learning and teaching online. Nonetheless, moving education online is bringing unprecedented challenges. For instance, learners may feel isolation online, massive content alternatives often overload learners and teachers who look for educational resources, and institutions are being challenged to ensure academic integrity in online exams. The increasing amount of learning-related data and high performance computing are enabling intelligent systems that can successfully support stakeholders. Bringing this intelligence to online education leads to a wide range of advantages, e.g., avoiding manual error-prone tasks or providing learners with personalized guidance [START_REF] Chen | Artificial intelligence in education: A review[END_REF].

As artificial intelligence research and development is getting more mature, and the corresponding outputs are being deployed at scale in real-world contexts, the crucial role of using automated systems, as an additional support for stakeholders during decision making processes, becomes more evident nowadays.

Current research has greatly expanded our understanding on such artificial intelligence, but there are less investigations on how it applies to online education. Data, methods, tools, and applications in this area are still limited, though they promise to proliferate in the next years. Further, more research and questions remain to be answered to bridge technological, social, pedagogical, and ethical aspects within intelligent systems.

This special issue brings together high-quality original research results reporting advances in the state of the art of online education systems empowered by artificial intelligence, cover-35 ing different levels of the experimental pipeline, including but not limiting to data collection, computational models, and applicative systems. The rest of this article is structured as follows: Section 2 briefly presents the articles included in this special issue, and Section 3 provides concluding remarks.

Content of This Special Issue

The submissions received in the context of this special issue are peer-reviewed on the basis of relevance for the special issue, novelty, originality, significance, technical quality and correctness, quality and clarity of presentation, quality of 45 references and reproducibility. In the end, this special issue contains 12 articles that advance the state-of-the-art, considering different tasks, ranging from community analysis, student risk and success prediction to course recommendation, cognitive state analysis and classification, and teaching content anal-50 ysis and classification. These articles target a wide range of educational scenarios, including massive open online courses (MOOCs) and higher university. The richness of the research in this special issue shows how learning analytics and educational technologies research have many different perspectives that join 55 in one goal: understanding and improving student learning.

Community Analysis and Detection. The authors in this special issue address the analysis and detection of communities in educational settings from several perspectives.

The article "Maximal Cliques Based Method For Detecting 60 And Evaluating Learning Communities in Social Networks", by Adraoui et al. [START_REF] Adraoui | Maximal cliques based 260 method for detecting and evaluating learning communities in social networks[END_REF], examines the efficacy of using a Maximal Cliques based method for detecting learning communities, including a dynamic evaluation (social interactions of learners) and a static evaluation (e.g., using demographic information).

65

The idea behind the authors' approach involves the evaluation of learners by communities, instead of using their individual production. The detection of communities proved to be relevant in order to support all the stakeholders (e.g., teachers and administrators) in understanding learners' needs and to finally 70 improve the educational process. The reliability and efficiency of the approach are shown using three real-world scenarios. Ruipérez-Valiente et al., in their article "Data-driven Detection and Characterization of Communities of Accounts Collab-orating in MOOCs" [START_REF] Valiente | Data-driven detection and characterization of 265 communities of accounts collaborating in moocs[END_REF], propose a clustering-based approach for the detection and characterization of different collaboration types in MOOCs based on student interactions with the learning platform, without having prior knowledge about the existence of such collaborations. The authors also investigate the behavioral characteristics of the detected communities of accounts (e.g., fruitful, free-riding, and illicit collaboration). Experiments on two MOOCs show that the proposed approach is a viable way for automatically identifying community of accounts and that, while collaborations in MOOCs are generally positive for the learning process, not all the identified students' collaborations can be considered as good or beneficial (e.g., collaborating in dishonest ways to facilitate course completion).

In their article "Learning Behaviours Data in Programming Education: Community Analysis and Outcome Prediction with Cleaned Data", Tan Mai et al. [START_REF] Mai | Learning behaviours data in programming education: Community analysis and outcome prediction with cleaned data[END_REF] focus on identifying communities of learners based on their behaviour in the event logs, instead of analysing the behaviour of each individual student. A further analysis contrast the behaviour of the communities and the final results of students. The experiments are conducted on two university programming courses with around 400 students 95 show that similar behaviour groups have similar performance measure by the final grade. While high performing communities are characterised by more practical related activities, low performing ones mostly passively engage with the course lesson materials. 100 Student Success and Dropout Prediction. This special issue sheds light on advances in the formalization, design, and development of models for student success and dropout prediction.

In their article "Student Success Prediction using Student Exam Behaviour", Kuzilek et al. [START_REF] Kuzilek | Student success prediction using student exam behaviour[END_REF] study the impact of us-105 ing temporal information from exam-taking behaviour on student's success prediction. They propose a new method for encoding students' exam states and use these encoded states as input of different typical predictive models. The experiments show that their proposed approach not only leads to a signifi-110 cant improvement in terms of performance prediction, but also allows to identify critical exam-taking patterns. Prenkaj et al., in their article "Hidden Space Deep Sequential Risk Prediction on Student Trajectories" [START_REF] Prenkaj | Hidden space deep sequen-275 tial risk prediction on student trajectories[END_REF], present an endto-end deep-learning approach based on raw time series and embedded information (e.g., navigational, forum-based, videobased and homework-based e-tivities) to address the student dropout prediction task. The proposed neural architecture exploits autoencoders to mitigate feature sparsity and stacked embedded gated recurrent units to extract latent information and 120 temporal dependencies even in presence of long temporal gaps. Experiments show that the proposed approach has superior performances in capturing long-term behavioral dependencies and outperforms a range of state-of-the-art shallow and deep learning baselines on two standard benchmarking datasets of on-125 line courses (XuetangX and KDDCup15) and a novel released dataset on online university degrees (Unitelma).

The article "Deep Cognitive Diagnosis Model for Predicting Students' Performance", by Gao et al. [START_REF] Gao | Deep cognitive diagnosis model for predicting students' performance[END_REF], proposes a new generative model of the relations between problems and skills, with 130 the aim of improving students' performance prediction and educational recommendations. The authors represent skills and problems as vectors whose dimensions correspond to difficulty and keywords, and rely on students' mastery of skills and skill interaction to model the problems' proficiency. They then com-135 pare their proposed model with two classical cognitive diagnosis models, two latent factor models and two deep learning based models on two datasets, showing that the proposed model has a better predictive performance and interpretability. with the concept of provider fairness for demographic groups of teachers that share the same continent of provenience. The authors consider the notion of fairness based on equity, which compare the share of recommendations of a group with its representation in the data. They assess the presence of disparities 160 on data coming from a MOOC platform by applying state-ofthe-art collaborative filtering approaches (ranging from pointwise to pair-wise as well as from memory-based to model-based algorithms). The authors find out that there are disparities in the visibility and exposure at expenses of smaller demographic 165 groups. These disparities are mitigated with a novel multi-class approach that regulates the visibility and exposure given to each group, without affecting recommendation effectiveness for the learners, and thus allowing cross-continent provider fairness.

Course

Cognitive State Analysis and Classification. Two articles of 170 this special issue focus on supporting a better understanding of students' cognitive states from diverse viewpoints.

Abate et al., in their article "Attention Monitoring for Synchronous Distance Learning" [10], introduce a system for providing indicators on the didactic efficacy of the lecture to the 175 teacher, avoiding the need of activating learner cameras while using a video conference system for synchronous distance lectures. A software module runs in background and locally on the learners' computers for tracing their blinks, gaze and expressions (no sensitive information is shared through the network), 180 while another software module automatically analyzes and aggregates information in a user interface provided to the teacher, including a heat-map that highlights the parts of the slide the learners are focusing on the most and the distribution of the classified expressions. Experiments with volunteers, ranging 185 from university students to employees engaged in training ac-tivities, result in positive feedback in terms of gaze tracking and evaluation questionnaires, from both learner and teacher sides.

The article "Classifying Students based on Cognitive State in Flipped Learning Pedagogy", by Shaw and Patra [START_REF] Shaw | Classifying students based on cognitive state in flipped learning pedagogy[END_REF], investigates students' learning while preparing for a lesson in a flipped classroom scenario by analysing their cognitive state based on their brain signals. Focusing on the EEG signal, the authors designed a method, based on a siamese neural network, that can classify students into three categories according to their attention. Experiments show that this approach outperforms other state-of-the-art classification methods. Once these sensors are more spread , this approach can help teachers identify students who are not paying enough attention and not learning despite putting effort into studying.

200

Teaching Content Analysis and Classification. Finally, the papers of this special issue investigate the automated analysis and classification of teaching material and strategies.

In their article "Is it a Good Move? Mining Effective Tutoring Strategies from Human-Human Tutorial Dialogues", 205 Lin et al. [START_REF] Lin | Is it a good move? mining effective tutoring strategies from human-human tutorial dialogues[END_REF] investigate automated approaches for detecting both effective and ineffective tutoring strategies, by mining a large-scale dialogue corpus of online human-human tutoring. First, the authors adopt a widely-used educational dialogue act scheme to describe the action behind the utterance (e.g., ask-210 ing/answering a question, providing hints). Then, they apply a sequence analysis on the inferred actions to identify prominent patterns closely related to students' problem-solving performance. Lastly, they use these labelled tutorial actions as input to a well-established machine learning approach to predict students' problem-solving strategies. Experiments on a large dataset of tutoring sessions contribute to a better understanding of tutors' as well as students' behavior in human-human online tutoring and show that the proposed approach can be practically used to locate (un)successful dialogues in an automated way.

Gasparetti, in his article "Discovering Prerequisite Relations from Educational Documents through Word Embeddings" [START_REF] Gasparetti | Discovering prerequisite relations from educational documents through word embeddings[END_REF], presents a novel method to discover prerequisites in documents, taking advantage of latent representations for their identification in a binary classification setting. The proposed methodology employs various machine learning algorithms and is tested on four different datasets which vary in terms of covered subjects and amount of instances. The results indicate that, although the underlying architecture is simple, the proposed approach achieves an accuracy close to complex deep learning ar-230 chitectures based on recurrent neural networks and transformers.

Conclusions

Intelligent systems empowered by data mining and machine learning and tailored to online education are fostering increasingly intense research to ensure that these systems can support stakeholders in an effective, efficient, adaptive and timely way. The articles included in this special issue cover a range of interesting topics and highlight important next steps in this active and rapidly evolving field of research and development. We hope that the readers will find this selection of articles informative and helpful in keeping themselves up-to-date on the current challenges and directions, and that the content of these articles can contribute to timely drive their future research progresses.

  40

  Recommendation. The design and evaluation of intel-140 ligent systems able to recommend courses of interest to students are the focus of two articles in this special issue. The article "ACMF: An Attention Collaborative Extended Matrix Factorization Based Model for MOOC Course Service via a Heterogeneous View", by Sheng et al. [8], focuses on the 145 problem of personalized course recommendation in a MOOC environment. The authors propose a new model, based on recent methodologies from the domains of graph learning and recommender systems, that captures structures and semantics. The experiments compare the proposed model against a number 150 of node-embedding baselines and recommendation methods on two datasets. The results show a good robustness against data sparsity and imbalance. The article "Enabling Cross-continent Provider Fairness in Educational Recommender Systems" [9] by Gomez et al., deals

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Preprint submitted to Journal of L A T E X Templates October 13, 2021

Acknowledgments

245

We thank all the authors for considering this special issue as an outlet to publish their research results in the area of intelligent systems for online education. We express our deepest gratitude to all the reviewers who devoted much of their precious time providing useful and thoughtful comments on the articles

submitted to this special issue. We warmly thank the Editor-in-Chief, the Special Content Editor, and the journal office team of FGCS, for their kind support, advice, and encouragements throughout the management of this special issue.


Olivier Pourret

Daniel Enrique Ibarra

The rise of preprints in Earth Sciences

A research article's preprint is its initial draft shared online, which is frequently (but not always) done before

EGUsphere (data accessed on January 02 2023). Some other regional preprint services also exist as well as more general ones (e.g. Irawan et al., 2022); a list can be found at https://asapbio.org/preprint-servers [START_REF] Kirkham | Systematic examination of preprint platforms for use in the medical and biomedical sciences setting[END_REF].

Preprints have numerous, well-established advantages for both researchers and the general audience (e.g., [START_REF] Bourne | Ten simple rules to consider regarding preprint submission[END_REF][START_REF] Sarabipour | On the value of preprints: An early career researcher perspective[END_REF]Pourret and Irawan, 2022).

Preprints, for instance, allow:

• The quick dissemination of research findings, which is important for time-sensitive studies (such as those conducted after natural disasters), for early-career researchers applying for jobs, or for any academic applying for grants or a promotion, given that journal-led peer review can take months or even years;

• Increased visibility and accessibility for research outputs due to the preprint's free uploading and viewing, especially for individuals who do not have access to paywalled journals or who have restricted access because of remote working (such as during lockdowns);

• Peer feedback that goes above and beyond what is offered through journal-led peer review, increasing the likelihood of collaboration through community input and discussion;

• Researchers to set priority (or a precedent) for their findings to reduce the possibility of being "scooped";

• Dismantling of silos that traditional journals sustain by exposing us to a wider range of research than we might otherwise encounter and providing a home for works that do not clearly have a traditional peer-review publication as their intended destination;

• Openness and transparency in research, with a focus on enhancing the overall standard, reliability, and reproducibility of findings. Despite these benefits, some authors point out that preprints without peer review raise a host of issues that may vary by discipline and publication type (e.g. [START_REF] Meinert | Thoughts on scientific publishing[END_REF]. In particular, they may come with a caveat that interpretations are subject to change and that they may or may not lead to actual peer reviewed publication. [START_REF] Pourret | On the Potential of Preprints in Geochemistry: The Good, the Bad, and the Ugly[END_REF] pointed out that the increased dissemination effect has the potential to be used to promote non-reproducible scholarship or fake news and adds an extra potential burden on readers.

Preprints may have some other disadvantages, including information overload, insufficient quality assurance, political influence, and outsized impact (e.g. [START_REF] Smart | The evolution, benefits, and challenges of preprints and their interaction with journals[END_REF].

Based on policies collated on Sherpa Romeo (https://v2.sherpa.ac.uk/romeo/) of the Earth Sciences journals, a majority of those journals do accept manuscripts preprinted prior to or during submission.

Overall, preprints have played a crucial role in advancing science for the benefit of humanity during the pandemic, according to the medical and scientific communities as well as the general people [START_REF] Besançon | Open science saves lives: lessons from the COVID-19 pandemic[END_REF]. They are now included in some major bibliographic databases. Even if not always allowed by some funding agencies (e.g. Australian Research Council, [START_REF] Lanati | Research Funding Bodies Need to Follow Scientific Evidence: Preprints Are Here to Stay[END_REF], preprints are now a recognized step in the publication of scientific research and will continue to be used.

Figure 1 .

 1 Figure 1. Cumulative numbers of preprints from EarthArXiv, ESS Open Archive and

  For example, preprints are now included in the flow chart publication of the open access platform of European funded projects Open Research Europe. Indeed, preprints are assisting in the modernization of our disciplines by reducing structural hurdles that prevent taxpayers, who frequently support knowledge development, from accessing science and knowledge, as well as by making research findings rapidly available to anybody who might benefit from them. The preprint landscape is moving fast, in early December 2022 PLOS announced in a press release partnership with EarthArXiv. Additionally, PLOS, in partnership with Dataseer, has just released the first Open Science Indicators dataset, which uses large-scale Natural Language Processing to analyze published research articles to identify and track Open Science practices (Public Library of Science, 2022). The first three indicators included are: data sharing, code sharing, and preprint posting. Importantly, these metrics are not intended to rate or rank journals or publishers, but rather to set benchmarks, monitor changes over time, and better understand the research community's use of Open Science practices such as preprinting. Nevertheless, preprints are certainly here to stay!