Samuel Guillemot

Keywords:

This study focuses on legacy writing and the development of the life-history business (e.g. family ghostwriters and writing workshops). A theoretical model is proposed to study the underlying mental processes that lead the elderly to consume such services. This model was empirically tested on a sample of 392 individuals aged from 60 to 92 years. Results highlighted the following: the role of generativity and death preparation reminiscence on identity preservation issues in later life, the strong desire to contribute to collective memories (i.e., to reach people outside of the family circle), and the social nature of the consumption of services that could be considered as a means to share emotions. The results of this study will lead to a more in-depth understanding of consumer behavior regarding the transmission and preservation of the self at end of life, and may also help service providers to improve their products and services.

The more individuals age, the more they are confronted with traumatic events that will, sooner or later, threaten their identity. These events may be both objective (e.g. loss of loved ones, deterioration of physical capabilities) and subjective (e.g. feelings of vulnerability, shortening of the limited time horizon view). When faced with these immediate or forthcoming identity upheavals, the elderly may be tempted to preserve this identity and/or to transmit it to future generations. Consumer research shows that common strategies include taking on the role of caregiver to ensure inter-generational cohesion, or that of grandparent to transmit family history and heritage [START_REF] Schewe | Role transitions in older adults: A marketing opportunity[END_REF], using symbolic rituals [START_REF] Bonsu | Do not go cheaply into that good night: Death ritual consumption in asante ghana[END_REF], and/or transmitting possessions [START_REF] Curasi | Maybe it is your father's oldsmobile: The construction and preservation of family identity through the transfer of possessions[END_REF][START_REF] Price | Older consumers' disposition of special possessions[END_REF][START_REF] Wallendorf | My favorite things: A cross-cultural inquiry into object attachment, possessiveness, and social linkage[END_REF].

Legacy writing has experienced a boom since the above-mentioned studies were published. The fragmentation of traditional family ties, the geographic dispersion of generations within a family, solitude, and the isolation inherent in modern lifestyles all contribute to the weakening of lineage links [START_REF] Argentin | Parler de son temps : récits de vie et ateliers d'écritures[END_REF] and may explain the emergence of legacy writing motives. As mentioned by [START_REF] Hunter | Leaving a legacy: Toward a typology[END_REF], "the extremely mobile nature of contemporary society is leading to a greater need for attachment in some way to the places and events of our past [START_REF] Relph | Place and placelessness[END_REF]. This perhaps explains the upsurge of autobiographical writing, concern with life histories (…). This may not have been so important in previous generations because of the strength of oral traditions transmitted within geographically proximate families, but it certainly seems to have great contemporary significance".

The personal historian, or family history ghostwriter, has developed into a veritable lifehistory business that makes it easier for individuals to transmit their life story. The emergence of these biography services has been praised in some sectors. For example, in the media, the preservation of memories was recently noted by several newspapers (including the Washington Business Journal, The Wall Street Journal and The New York Times) as a profitable business opportunity; in the marketing industry, Legacy Multimedia of Houston was awarded the 2012 AMCP Videographer Award of Distinction for its videotape service; and from a public policy/association perspective, some Alzheimer's groups encourage people in the early stages of the disease to make an oral recording of their memories while they still can.

Through studying legacy writing, the aim of this paper is to gain insight into identity issues, in particular the transmission and preservation of the self in later life. It will examine the motivations behind legacy writing, the origins of these motivations, and the nature and impact of different legacy writing motivations on the consumption of biographical services. The study is organized as follows. Based on an interdisciplinary literature review, the various concepts and theoretical dimensions will be linked by determining identity issues in later life and the underlying motivations behind creating a life story. In this respect, the study shows how these legacy-writing motivations can be combined expressions of more profound concepts such as life review and generativity. This theoretical background allowed us to develop several hypotheses on how motivations and their antecedents influence legacy-writing behavior and desire to use biographic services. These hypotheses were tested via a quantitative survey conducted on 392 people aged between 60 and 92 years, the results of which will be discussed considering theoretical and managerial implications. Finally, study limitations will be described and avenues of future research suggested.

TRANSMISSION AND PRESERVATION OF THE SELF AT END OF LIFE

Legacy writing, whether it be filmed, recorded, or written, reflects the research conducted on the transmission and preservation of the self at end of life, and an overview of these studies will enable the important issues to be highlighted.

Special "possessions", extended self-paradigm

The identity paradigm used in studies on preservation and transmission of the self makes a distinction between the core-and the extended-self [START_REF] Belk | Possessions and the extended self[END_REF]. In this framework, several authors have highlighted the strategies that elderly individuals use to preserve their identity through "solidification of identity" [START_REF] Belk | Possessions and the extended self[END_REF][START_REF] Unruh | Death and personal history: Strategies of identity preservation[END_REF]) and placing symbolic value on "special" possessions, thus considering these objects as an extension of their personality [START_REF] Curasi | Maybe it is your father's oldsmobile: The construction and preservation of family identity through the transfer of possessions[END_REF][START_REF] Curasi | How individuals' cherished possessions become families' inalienable wealth[END_REF][START_REF] Price | Older consumers' disposition of special possessions[END_REF][START_REF] Wallendorf | My favorite things: A cross-cultural inquiry into object attachment, possessiveness, and social linkage[END_REF]. Therefore, the transmission of these objects corresponds to several motivations such as "enacting a kin-keeping role" (the person responsible for preserving family cohesion), or "achieving symbolic immortality". Special objects have various meanings at the end of life: the valuable object of recognition (e.g. a trophy symbolizing a reasonably successful athletic "career") enables the recollection of life moments and of particular events experienced in the past (e.g. a ring or a piece of jewelry symbolizing a particular relationship). When this object is offered as a present or a legacy to someone who will know how to preserve its meaning, for the giver, this is a way of being remembered [START_REF] Price | Older consumers' disposition of special possessions[END_REF]. It also enables the transmission of individual and family values and is a vehicle for intergenerational transmission [START_REF] Goldberg | Réaliser une boîte à souvenir[END_REF]. Furthermore, it has a therapeutic value and, in particular, serves as a point of anchorage and stability [START_REF] Wapner | Cherished possessions and adaptation of older people to nursing homes[END_REF].

Transmission and preservation of the self through self-extensions raises the issue of the loss of meaning that is linked with these objects. [START_REF] Price | Older consumers' disposition of special possessions[END_REF] state that deciding to part with an object in which we have invested a part of our identity stems from a complex thought process that associates the notion of finality, the meaning associated with the object, and the relationship with the object's recipient.

Legacy writing, "narrative identity paradigm"

Since [START_REF] Belk | Possessions and the extended self[END_REF], one of the major developments in consumer research on identity has been on the structuring of the consumer's sense of identity in the form of a narrative [START_REF] Escalas | Using narratives to discern self-identity related consumer goals and motivations[END_REF][START_REF] Fournier | Consumers and their brands: developing relationship theory in consumer research[END_REF][START_REF] Giddens | Modernity and self-identity, self and society in the late modern age[END_REF][START_REF] Thompson | Caring consumer: gendered consumption meanings and the juggling lifestyle[END_REF][START_REF] Thompson | Interpreting consumers: A hermeneutical framework for deriving marketing insights from the texts of consumers' consumption stories[END_REF][START_REF] Thompson | Trying to be cosmopolitan[END_REF]. According to [START_REF] Ahuvia | Beyond the extended self: loved objects and consumers' identity narratives[END_REF], "since the publication of [START_REF] Belk | Possessions and the extended self[END_REF], narrative theory, in which our sense of identity is structured as a story, has emerged as the dominant conceptualization of the self. This means that in addition to seeing one's identity as a list of attributes […] these attributes are linked in memory to key episodes in one's life, which in turn are strung together to form a story". For McAdams "the only conceivable form for a unified and purposeful telling of an individual life is a story" [START_REF] Mcadams | Personality, modernity, and the storied self: A contemporary framework for studying persons[END_REF], particularly when considering the problems of selfhood under the conditions of modernity and postmodernity [START_REF] Mcadams | Unity and purpose in human lives: The emergence of Identity as a life story[END_REF]. Therefore, it is not surprising to note that "the growing popularity of keeping journals, diaries and other autobiographical devices neatly parallel[s] the rise of modernity in the West [START_REF] Giddens | Modernity and self-identity, self and society in the late modern age[END_REF], for making sense of the modern self as it changes over time centrally involves the construction of self-narratives" (ibid).

As a result, if we take into account the "narrative self" identity paradigm, the preservation and transmission of identity may correspond to the writing and transmitting of a life story. Consequently, a deeper understanding of legacy writing behavior could lead to more in-depth knowledge about the identity issues experienced at the end of life.

THE DIFFERENT TYPES OF LEGACY WRITING MOTIVATIONS

Theoretical research indicates that legacy writing could be a means of putting the past into perspective, of rediscovering its original meaning, and of providing the "official version" of the story. A review of the multidisciplinary literature (sociological, psycho-sociological, gerontological, and autobiographical) on the subject allowed us to identify several underlying motivations for writing a life story. These motives can be considered to be either communal or agentic. [START_REF] Bakan | The duality of human existence: Isolation and communion in western man[END_REF] states that communal refers to friendship, love, and caring for others, whereas agency refers to self-mastery, status, and victory. After a detailed description of each of these motivations, we will consider them in light of the motivations behind the transmission of special objects.

Agentic motivations of legacy writing

In the autobiographical literature, the quest for recognition is described as one of the pillars of personal writing, providing the narrator with an opportunity to focus the account on personal history [START_REF] May | L'autobiographie[END_REF]. First, the life history can give individuals the opportunity to express what has value in their life and to depict themselves in situations they feel proud of, such as a diploma, a career, a sporting achievement, or a life path [START_REF] Hubier | Littératures intimes : Les expressions du moi, de l'autobiographie à l'autofiction[END_REF]. Therefore, the life story enables an individual's knowledge, skills, and accomplishments to be identified [START_REF] Rubinstein | Reminiscence, personal meaning, themes, and the "object relations" of older people[END_REF]. The motive can be explicitly posthumous and the role of the story is to survive the author [START_REF] Zarca | Triple démarche pour une transformation de soi. Psychanalyse, socio-analyse et autobiographie[END_REF]. The life story enables the narrator to ensure that he/she will not be forgotten after death and to communicate what he/she would like to be remembered for [START_REF] Caradec | Vieillir après la retraite, approche sociologique du vieillissement[END_REF]. After death, there are no more opportunities to negotiate a new identity [START_REF] Bonsu | Do not go cheaply into that good night: Death ritual consumption in asante ghana[END_REF]. In this sense, elderly people tend to present themselves as they would like to be remembered [START_REF] Unruh | Death and personal history: Strategies of identity preservation[END_REF] and as the hero of a complete and unique life [START_REF] Tarman | Autobiography: The negotiation of a lifetime[END_REF], for example.

In addition, the literature highlights the liberating power of writing an account as it allows the narrator to express what has long been suppressed and serves as an outlet for malaise. In his time, Rousseau was one of the first illuminati to use his confessions to justify his conduct. Thus, the desire to confess, to give one's version of the facts, can be a driving force behind legacy writing. Similarly, the life story provides an opportunity to defend oneself against accusations deemed unfounded, to give one's version of the facts, to correct, or to deny [START_REF] Lejeune | Signes de vie: Le pacte autobiographique 2[END_REF].

Communal motivations of legacy writing

Legacy writing is not only about the narrator, it is also a way of communication; recalling lived experiences can be a form of socialization similar to social networking. Elderly people age with a disappearing world in mind and are, hence, the protectors of our collective identity. Therefore, it is the desire to transmit, demonstrate and share that shapes many life stories (Milion-Lajoinie, 1999). Two levels of communal motivations can be put forward: family and collective.

Family communal motivations refer to the need to transmit something before it disappears because finiteness is a menace to family memory. In this sense, the writing of a life story is described as a means of transmission enabling people to "pass on the baton" to younger members of a family or a community [START_REF] Sanchez | Discours oraux, discours écrits, les seniors et l'écriture de soi[END_REF]. Legacy writing is a support for individual memory, but also for family, collective, and transgenerational memory [START_REF] Gucher | Vieillir en mémoire paysanne: des lieux, des liens, continuité et permanence de sens et d'usage[END_REF]. Writing a life story is a way of remembering those who have died and of making their identity known to the younger generation [START_REF] Zanone | L'autobiographie[END_REF].

Collective communal motivations refer to the life story as a means of representing collective destiny because the narrator can recount witnessed or experienced events. The desire to bear witness shapes many life stories and as such, individual biographies become sources for tomorrow's sociologists, historians, or other researchers (Fabre, 2002;[START_REF] Lejeune | Signes de vie: Le pacte autobiographique 2[END_REF][START_REF] Lyons | La culture littéraire des travailleurs, autobiographies ouvrières dans l'Europe du XIX siècle[END_REF].

Considering that each type of motivation supposedly influences legacy writing behavior, we have formulated the following series of hypotheses: H1: Agentic legacy writing motivations have a positive influence on writing behavior H2a: Family communal legacy writing motivations have a positive influence on writing behavior H2b: Collective communal legacy writing motivations have a positive influence on writing behavior Additionally, we wish to gain further insight into the consumption of biographic services, which range from step-by-step guides (books or software) for writing/recording chapter one of the life story to the Autobiography/Memoir Class(room). Many previous studies have examined the role of behavioral intentions in predicting actual behavior and this previous research is primarily based on the Theory of Reasoned Action developed by [START_REF] Ajzen | Understanding attitudes and predicting social behavior[END_REF]. By considering the meta-analyses available on the intention-behavior relationship [START_REF] Hale | The theory of reasoned action[END_REF], the theory of reasoned action suggests that behavioral intentions are a good indicator of actual behavior. Therefore, the following hypothesis can be put forward:

H3: An individual engaged in a writing behavior has a positive intent to use biographic services

ANTECEDENTS OF THE LEGACY WRITING PROCESS

The key role of the "final life review" and reminiscence [START_REF] Price | Older consumers' disposition of special possessions[END_REF] use life review theories to explain "preservation" and "transmission of the self" behaviors. Life review is a normative process that all people undergo when they realize their life is coming to an end [START_REF] Butler | The life review: An interpretation of reminiscence in the age[END_REF] and implies a search for meaning through reflection on one's life experience [START_REF] Coleman | Uses of reminiscence: Functions and benefits[END_REF].

While life review or reminiscence are not age specific, some authors refer to a "final life review". This is the use of one's past to prepare for and come to terms with the idea of death (death preparation reminiscence - [START_REF] Webster | The reminiscence functions scale: A replication[END_REF]. Indeed, when end of life is approaching, individuals conduct a final "review" [START_REF] Mcadams | Unity and purpose in human lives: The emergence of Identity as a life story[END_REF]; the "story" is coming to its end and people become historians of their own life. There is the need to explain things, recall personal stories constructed throughout life, and establish the official account of one's life as a sort of anthology of the self. In retirement homes, geriatricians and other relevant specialists note that many elderly individuals are committed, to varying degrees, to the structuring of a coherent life story that they "write in their head" [START_REF] Argentin | Parler de son temps : récits de vie et ateliers d'écritures[END_REF][START_REF] Freyssenet | Psychopathologie quotidienne des petits vieux[END_REF][START_REF] De Givenchy | Ma vie est un vrai roman…[END_REF]Lalive d'Epinay, 2009). For McAdams, "the construction of coherent life stories is an especially challenging problem for adults living in contemporary modern and postmodern societies, wherein selves are viewed as reflexive projects imbued with complexity and depth, ever-changing and yet demanding a coherent framing". It is precisely this "final" life story that would allow individuals to find meaning and unity where [START_REF] Gergen | The saturated self: Dilemmas of identity in contemporary life[END_REF] sees only multiple selves and fractured stories.

The final life review process is a form of reminiscence that is easier for people who tend to use their memory to establish and clarify important dimensions of their personality, and who use memories to come to terms with the proximity of death and existential questions on end of life (death preparation reminiscence, [START_REF] Webster | The reminiscence circumplex and autobiographical memory functions[END_REF]. It is reasonable to think that these functions could cultivate different motives. Since identity is negotiated by ante mortem experiences [START_REF] Bonsu | Do not go cheaply into that good night: Death ritual consumption in asante ghana[END_REF], the following hypothesis (H4) can be put forward: H4a: Death preparation reminiscence has a positive influence on agentic legacy writing motivations H4b: Death preparation reminiscence has a positive influence on family communal legacy writing motivations H4c: Death preparation reminiscence has a positive influence on collective communal legacy writing motivations

The importance of generativity

The concept of generativity was first introduced over 50 years ago by Erik [START_REF] Erikson | Identity and the life cycle: Selected papers[END_REF] in his theory of the human life cycle. This theory of human development contains eight stages of human life, of which "generativity versus stagnation" is the seventh. One of the first experiences of generativity may be expressed through child-bearing and -rearing. However, a broader view of this concept includes different life settings such as the proclivity to volunteer and participate in community activities [START_REF] Mcadams | Generativity and adult development: How and why we care for the next generation[END_REF]. According to Erikson, Kotre (1999) defined generativity as the desire to live in such a way so that what is created will outlive one's own life. For [START_REF] Mcadams | The anatomy of generativity[END_REF], the concept of generativity consists of the following seven elements: "constellation of inner desire, cultural demand, conscious concern, belief, commitment, action and narration revolving around and ultimately justified in terms of the overall psychological goal of providing for the survival, well-being and development of human life in succeeding generations" (p. 9). More specifically, based on [START_REF] Bakan | The duality of human existence: Isolation and communion in western man[END_REF], McAdams considers there to be two inner desires that form the foundation of generativity: communal desires and agentic desires, the characteristics of which have been described above. [START_REF] Erikson | Identity and the life cycle: Selected papers[END_REF] original conception of generativity suggests that it is embedded in the last stages of life and as such, appertains to older individuals. However, [START_REF] Kotre | Make it count: How to generate a legacy that gives meaning to your life[END_REF] expanded the concept and freed it from a fixed chronological position. For Kotre, Erikson does not distinguish between different types of generativity and different aspects of generativity may come and go over the life course. Thus, "societal generativity", which is characterized by caring for younger adults, serving as a mentor, and generally contributing to the continuity of subsequent generations, begins around midlife and remains predominant until late adulthood [START_REF] Schoklitsch | Generativity and aging: A promising future research topic?[END_REF]. [START_REF] Vaillant | Aging well[END_REF] extended this: in his theory of adult development he introduces an intermediate stage between generativity (vs stagnation) and integrity (vs despair). It is the "keeper of the meaning" stage when focus is placed on the conservation and preservation of collective products and, consequently, on culture and institutions rather than on child development. [START_REF] Hunter | Leaving a legacy: Toward a typology[END_REF] refer to "cultural generativity" as a "vehicle that carries the meaning of life from one generation to another". Thus, faced with the end of one's existence, aging individuals will call upon their memories in a final life review process and will construct "a generative script […] to leave a legacy of the self to the next generation" [START_REF] Mcadams | A theory of generativity and its assessment through self-report, behavioural acts, and narrative themes in autobiography[END_REF]. "The generativity script functions to address the narrative need for the sense of an ending" (ibid). This is why [START_REF] Schoklitsch | Generativity and aging: A promising future research topic?[END_REF] considered narration to be especially important in old age. For McAdams & de St Aubin (1998, p 9): "A person's life story can itself be a kind of generative legacy, for the story itself is psychosocially created and maintained and sometimes offered to others (e.g. one's children or others who may benefit from knowing about one's life) as a lesson or gift".

As such, even though the autobiography relates to a generative action, it is derived from a generative commitment (corresponding to certain legacy writing motives) underpinned by a generative interest which has future generations in mind (McAdams, Holly & Maruna, 1998).

Recent research in this field identifies several generative interest dimensions [START_REF] Urien | On the role of generativity and self-enhancement values in eco-friendly behavioral intentions and environmentally responsible consumption behavior[END_REF], two of which seem to be antecedents to the legacy writing motives of passing on and posterity: "Passing on" deals with the transmission of skills or know-how to the next generation and, therefore, it seems legitimate to formulate the following hypothesis (H5):

H5a: an individual's interest in transmitting elements (know-how, etc.) to future generations (the passing on component of generative interest) has a positive influence on family communal legacy writing motivations H5b: an individual's interest in transmitting elements (know-how, etc.) to future generations (the passing on component of generative interest) has a positive influence on collective communal legacy writing motivations "Posterity" relates to the posthumous memory of the self. In this case it may be linked to agentic motives (flattering and mending the ego, being remembered) by using a form of the relatively obscure generativity identified by [START_REF] Kotre | Intergenerational buffers: The damage stops here[END_REF]. This results in egocentric behaviors in which the individual considers him/herself to be a model, or which manifest themselves in forms of rejection or denunciation. From this, the following hypothesis (H6) can be suggested:

H6: an individual's interest in being remembered by future generations (the posterity component of generative interest) has a positive influence on agentic legacy writing motivations

HYPOTHESIS TESTING

The model that is to be tested takes into account all of the hypotheses, which range from related legacy writing antecedents to motivations, and up to behavioral intentions. In this section, we empirically test the model.

Measurement

This study used measuring tools that had previously been tested and validated. A part of the legacy writing motivations scale designed intentionally for an aging population [START_REF] Guillemot | Legacy writing among the elderly: Conceptual bases, dimensioning and a proposed scale for measuring motivations[END_REF] was used. The original scale is composed of 20 items divided into six dimensions representing different legacy writing motivations. We used 12 items of the original scale for the present study: six representing the agentic motivation (labeled flattering and mending the ego in the original scale) and six for communal motivations (labeled transmitting and bearing witness)

To measure the final life review process, the death preparation reminiscence dimension of the Reminiscence Functions Scale (RFS -Webster, 1997) was used.

The "posterity" and "passing on" dimensions of generative interest were studied using the Loyola Generative Scale (LGS -McAdams & de St Aubin, 1992)adapted by [START_REF] Urien | On the role of generativity and self-enhancement values in eco-friendly behavioral intentions and environmentally responsible consumption behavior[END_REF] and composed of three items for each of the two dimensions.

We then defined three items to represent legacy writing behavior as described in the literature: writing a memoir/autobiography, writing down memories, or writing a personal diary. The various types of responses represent a degree of growing commitment in writing behavior that range from "not interested" to "already involved in the writing process". The latter relates to the writing process itself, whether it is in progress or finished. Although the scale is not metric, the data may be estimated in a structural equations model as the modalities reflect a degree of growing commitment [START_REF] Byrne | Structural equation modeling with EQS: Basic concepts, applications, and programming[END_REF]. In such a case, estimation by the maximum-likelihood procedure with the [START_REF] Satorra | Scaling corrections for chi-square statistics in covariance structure analysis[END_REF] corrected coefficients of significance guarantees reliable results (DiStephano, 2002).

Finally, the intent to consume biographic services was operationalized using item measurements representing the most well-known learning (writing workshop, methodological workshop) and co-production (private biographer) services. All items used a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree) and a 4-point rating scale for intent to consume. The final list of items is presented in appendix 1.

Data Collection

Data were collected in France by self-administered questionnaires. France is representative of Western countries in terms of population aging. According to the French National Institute of Statistics and Economic Studies (Insee), the over-60 age group currently represents 23% of the population and should account for over one third of the population in 2060 [START_REF] Blanpain | Projections de population 2007-2060 pour la France métropolitaine[END_REF]. Before proceeding to the data collection process, it was necessary to ensure measurement scale stability in a French cultural context. This phase had already been carried out for the scales of legacy writing motivations and for generativity, and the same process was adopted for the reminiscence scale. Previously, this scale had been translated into French according to the "backtranslation" method and submitted to a sample of 169 persons aged 60 years and over. Treatment of data via exploratory and confirmatory factorial analyses indicated a stable structure by retaining seven items (four for the "identity" dimension and three for "death preparation"). Eliminating some items does not alter the nature of the structure as this is a reflexive measure indicator.

The final data collection contained 392 responses (table 1). The questionnaires were presented as being based on a "memories" theme and were distributed (with a stamped addressed envelope enclosed) in potential meeting places for retired persons: universities of the third age, associations, offices and pensioners' clubs. A return rate of over 42% was recorded, thus illustrating peoples' interest in the subject.

Validation of the Measurement Instrument

The objective of this section is to validate the measurement instrument using a confirmatory factor analysis, as per the procedure of Anderson and Gerbing (1988) and the structural equations method (EQS 6.1 software). Jöreskog's rhô coherence coefficients (are always superior to 0.7 (Table 2)a threshold which is commonly accepted as ensuring the reliability of measuring instruments (Fornell & Larker, 1981). Next, the convergent validity was verified when the links between the latent variable and its indicators were significant and when each indicator shared more variance with its construct than with its associated error term [START_REF] Steenkamp | The use of LISREL in validating marketing construct[END_REF]. These conditions are concretely filled if the z test associated to each of the factorial contributions is > 1.96 and when the average variance extracted (AVE) for each dimension is > 0.5. This is the case here (Table 2). Finally, discriminant validity is also ensured since the constructs are different both theoretically and empirically. Table 3 shows that the correlations between the two constructs are less than the square root of their AVEs (diagonal term), which means that indicators of a same dimension share more variance between them than with those of other dimensions.

RESULTS

The fit indices of the model (² =745; df = 309 (p = .00); CFI = .90; RMSEA = .062 [.056-.067]) are acceptable. All of the hypotheses are verified. The structural standardized coefficients are presented in figure 1.

Figure 1. Model Three main conclusions can be drawn from the empirical test. Firstly, our study theoretically highlights and empirically confirms that legacy writing motives are based on the capacity for structured reminiscence to confront existential questions about end of life and on a direction towards the next generation (based on the memory that individuals will leave behind and on aspects that they wish to transmit). Together, those exogenous variables explained 39% of the variance of agentic motivations, and also 39% of communal motivations (respectively 16% and 23% for the family and collective level).

Secondly, collective communal motivations have a relatively greater impact (.37) than family communal (.15) and agentic (.16) motivations on writing behavior (r²=.25).

Thirdly, the Lagrange test put forward significant effects that were not expected: the direct effect of both family (.19) and collective (.13) communal motivations on the desire to use biographic services (r²=.25).

DISCUSSION

Considering the narrative self-identity paradigm, preservation and transmission of the self correspond to the preservation and transmission of one's history, and we have shown that legacy writing could complement the role held by special objects in the extended-self paradigm. The study provides further insight into the antecedents of such identity issues, the key role of collective communal motivations in legacy writing behavior and the social nature of biographic services consumption.

A better understanding of the identity transmission and preservation process

The central question is whether these new developments can benefit research on preservation and transmission of the self in end of life. This study sheds light on several new elements in this respect: it shows how (i) the motives behind the creation of a life story originate and, in particular, clarify the roles of generativity and death preparation reminiscence, and (ii) that the type of motivations behind legacy writing are communal or agentic.

From a managerial perspective, generativity and family communal motivations are already taken into account with marketing arguments such as "creating a memoir is a great way to connect generation and preserve memories". Conversely death preparation reminiscence and agentic motivations appear to be largely forgotten. However, numerous studies have shown that there are many advantages to coherently structuring one's life story. It not only has a positive influence on mood [START_REF] Fallot | The impact of mood on verbal reminiscing in late adulthood[END_REF], life satisfaction [START_REF] Cook | Effects of reminiscence on life satisfaction of elderly female nursing home residents[END_REF], well-being [START_REF] Haight | The therapeutic role of a structured life review process in homebound elderly subjects[END_REF], depression [START_REF] Bohlmeijer | Effects of reminiscence and life review on latelate depression: A meta-analysis[END_REF], and anxiety when facing death [START_REF] Jones | Life review following critical illness in young men[END_REF], but it also resolves memory problems (Hirsch & Mourtoglou, 1999). It gives the sensation of being in control of one's life as opposed to the sense of powerlessness felt when facing the loss of reference points and identity linked to the aging process. These arguments may be used by service providers in addition to generativity-related arguments.

The key role of collective communal motivations

The identified legacy writing motivations correspond to the motivations behind transmitting special objects at the end of life, but there is a difference between them: the collective communal motivation does not appear for special objects but it is central to the legacy writing process. Indeed, the impact of collective communal motivations on writing behavior is double the impact of agentic and family communal motivations (with reference to the empirical test). This result could be explained as follows: the act of explicitly laying out one's life story in writing makes it possible to ease the fear associated with the loss of meaning. It enables the writer to expand the circle of potential receivers, namely to people outside the family circle. A family's lack of interest can indeed be countered by the addition of other, sometimes unknown, readers who will know how to fully appreciate the meaning of the story.

Legacy writing appears to be a powerful way for individuals to satisfy their desire to contribute to collective memory. The narrator may represent a collective destiny by becoming, for example, the village historian or describing a bygone profession [START_REF] Lecarme | L'autobiographie[END_REF]. Legacy writing service providers could put narrators and researchers (e.g. geographers, historians or sociologists) interested in this type of testimony in touch with one another.

Consumption of services as a way of "sharing"

We found a direct link between communal motivation and the desire to use biographic service without the intent to engage in a writing behavior. Theoretically, this result is understandable: it could be derived from a request made by grandchildren or children wishing to gather family memories, or obtain information about certain events. This result reveals the social nature of legacy writing that has proved to be a means of sharing reminiscences with family and/or peers. Biographic services then become a mean of putting emotions, feelings, images, etc. into writing.

Biographic services are valued because they provide skills and a support for the life story and above all, because they create favorable conditions for sharing and exchange. For this reason, based on Rimé's theory of the Social Sharing of Emotion (2005), we recommend that providers develop group writing workshops. Indeed, consumers may place equal value on being listened to, criticized (for the sake of improvement) and reacting to the memories of others. Elderly individuals may have things that they would like to tell future generations, but also more simply, they have things they want to tell and share with other people.

LIMITATIONS AND AVENUES OF RESEARCH

The results of the study must be interpreted by taking several limitations into account and this highlights the need for future research. One of these limitations relates to the generalization of the results. It would be worthwhile repeating the study on other populations and, in particular, in other cultural or religious contexts. Extending the research should take into account the impact of environmental factors (financial resources, free time and how it is used, etc.) and potentially moderating variables (personality traits, tendency to procrastinate, level of self-esteem or sense of self-efficacy, etc.).

Table 1 .

 1 Summary profile of informants

	Gender		Age		Family
	Female	251	Age range	60-94	No children	45
	Male	141	Average age	68.40	Children, no grandchildren	75
					Children and grandchildren	272

Table 2 .

 2 Convergent Validity Testing

	Construct	Item	Standard Loading	Z Test Value	Joreskog rhô ()	Convergent validity rhô (vc)
	Legacy writing motivations
	Agentic motivations	AGE1	.75	>10	.87	.52
		AGE2	.81
		AGE3	.75
		AGE4	.55
		AGE5	.69
		AGE6	.75
	Family communal	FCM1	.63	>11	.78	.55
	motivations	FCM2	.79
		FCM3	.79
	Collective communal	CCM1	.74	>11	.80	.58
	motivations	CCM2	.83
		CCM3	.70
	Antecedents to legacy writing motivations
	Death Preparation	DPR1	.78	>15	.86	.67
	Reminiscence	DPR2	.87
		DPR3	.80
	Posterity Generativity PGE1	.82	>15	.85	.65
		PGE2	.76
		PGE3	.83
	Passing on Generativity POG1	.78	>8	.76	.52
		POG2	.76
		POG3	.60
	Effects of legacy writing motivations
	Writing behavior	WBE1	.88	>7	.79	.57
		WBE2	.89
		WBE3	.39
	Desire to consume	BSI1	.93	>10	.84	.64
	biographic services	BSI2	.83
		BSI3	.60

Table 3 .

 3 Correlations between Latent Constructs

		AGE FCM CCM DPR PGE POG WBE BSI
	AGE	.72
	FCM	.45	.74
	CCM	.49	.66	.76
	DPR	.44	.21	.24	.82
	PGE	.53	.22	.37	.31	.81
	POG	.35	.27	.33	.10	.59	.72
	WBR	.36	.40	.51	.31	.19	.24	.75
	BSI	.40	.39	.39	.37	.27	.22	.48	.80
	Note: AGE = AGentic Motivations, FCM = Family Communal
	Motivations, CCM = Collective Communal Motivations, DPR =
	Death Preparation Reminiscence, PGE = Posterity GEnerativity
	posterity, POG = Passing On Generativity, WBE = Writing behavior,
	BSI = Biographic Services Intention
	All significant at 5% level

Another important limitation is the individual's relationship with death. Like in other studies on special objects, it is considered here as an axiom, as a self-evident and unquestionable fact. It would thus be interesting to test the impact of certain sub-dimensions of individuals' attitudes towards death on the behavior of legacy writing, be it on the basis, motives, or act of writing. Effectively, the fear of death [START_REF] Florian | Fear of personal death and positive life regard[END_REF] contains certain sub-dimensions such as the loss of personal fulfillment, self-annihilation, the loss of social identity, consequences for loves ones, transcendental consequences, or even punishment after death. These sub-dimensions could have a general impact on the preservation and transmission of the self in ways that are yet to be determined, and more specifically, on the behaviors linked to legacy writing.

In this study, we contrasted special objects with legacy writing, but should they not be understood as complementary? This question is being raised more often with the rise of digital technology. Some objects that hold meaning, such as photographs or private correspondence, now tend to only exist in digital form, which means that memories are also captured and distributed by digital possessions (e.g. digital photos) [START_REF] Belk | The extended self in a digital world[END_REF]. Some services that are being developed (such as PartingWishes.com and MyWonderfulLife.com) recommend dealing with the digital legacy of e-mails, social media, and other online traces as well as declaring an executor of one's "digital estate" [START_REF] Belk | The extended self in a digital world[END_REF]Carroll & Romano, 2011).

APPENDIX. Measurement Instrument

Table A1. Life-story writing motivations measurement scale I would like to write my life story … (1 = strongly disagree, 5 = strongly agree)

Construct and Item

Cronbach's Alpha Agentic motivations

.86 -To talk about the interesting things I have done in my life -To highlight things I have done and am proud of -To highlight things about myself that others are not necessarily aware of -To help me clarify a period in my life -To tell the truth about certain things that happened in the past -To justify certain things I did in the past

Family communal motivations

.83 -To tell the younger generation about family members who have died -To transmit family values -For the younger members of the family who want to know about their roots

Social communal motivations

.84 -To leave a trace of the way we lived, so that future generations can picture our way of life -To leave a testimonial, because it is a sort of heritage you pass on to future generations -To preserve certain aspects of my culture that are disappearing Table A2. Generativity and Reminiscence measurement scale (1 = strongly disagree, 5 = strongly agree)

Construct and Item

Cronbach's Alpha Passing on Generativity

.74 -I have important skills that I try to teach others -I try to pass on the knowledge I gained through my experiences -I have made and created things that have an impact on other people Posterity Generativity

.84 -I think that I will be remembered for a long time after I die -Others would say that I have made unique contributions to society -I feel as though my contributions will exist after I die Death preparation reminiscence .85 -I remember my past because it helps me prepare for my own death -I remember my past because I feel less fearful of death after I finish reminiscing -I remember my past because it helps me to cope with thoughts of my own mortality


Regina Bernhaupt
email: r.bernhaupt@tue.nl

Social Media -A Systemic Change Perspective

Keywords: Social Media, Kpop, Systemic Change

Social media would not have been possible without the advances in the field of human-computer interaction (HCI). It was laying the basis for interactive systems early on when computers became personal, focused on how humans would not only work collaboratively, but how people could connect and socialize beyond boarders, be it organizational or geographical. Social media has changed society dramatically. From a systemic change perspective, the interplay between people and technology was moving from a single user interacting with a system, to groups of users interacting with a variety of connected systemsimpacting companies, organizations, communities and societies. This chapter gives a brief and simplified overview on the history of social media, followed by a systemic change oriented analysis how social media is changing the way people live, how they socialize and make friends. It then focusses on how societies change on national and international level using as an example the recent twitter activities of Kpop fans during the US presidential election campaign showing how new organizations and groups of people start to interact in ways that were unimaginable 15 years ago.

Introduction

Meet the Dutch couple, Sara Park and Jesse Jansen, and their 12 year old daughter Emma. Sara is communicating with her Korean parents via Kakao [START_REF] Kakaotalk | [END_REF], she started a trello board [START_REF] Trello | [END_REF] to organize the neighborhood activities and spends quite some time on Instagram following her favorite fashion brands.

Jesse is working at an international company for hardware technologies and social media is a central part of his daily work as well as family life. Jesse uses WhatsApp not only to reach out to his co-workers but organizes his cooking club activities and all the sharing of recipes, invites and of course all the joking, in a WhatsApp group for more than three years now.

Emma is not allowed to use Facebook, and her parents are strict on the set age limit of 13 to have a Facebook account. Emma does not mind, her main interest is to watch funny TikToc [24] videos and everything is anyway shared via WhatsApp messages with her friends, typically distributing Twitter and YouTube content and related discussions. When it comes to Emma rambling about Kpop, her parents are just rolling their eyes. For Emma the type of BLINK or ARMY 1 subgroup she ships 2 (and why the pink hair of her favorite idol was so much better than now the blue hair of the leader of the kpop group) are central for her daily communication. But Emma was surprised last week, when she was able to follow the political discussion her parents had with friends over dinner, when she knew more than her parents about the twitter groups that were spamming racist twitter channels and how ARMY had helped to book seats for an event with the US president to influence attendance [START_REF]Presidential Elections 2020[END_REF].

As the Park-Jansen family demonstrates, social media has become not only an integral part of business and family life, it is interwoven in local groups and neighborhoods, and now reaches beyond to impacting society on a broader level. There is a plethora of new services, platforms and possibilities to enable users to connect, share, discuss and communicate, allowing everyone to find and use their own personal mix. In this sense we have become even closer to McLuhans "the medium is the message" [START_REF] Mcluhan | Medium is the Message[END_REF].

In the following a brief overview on the history of social media is presented. Then the POISE-framework is presented, describing how social media can be analyzed and understood based on three relations between people, system and society. The chapter concludes with some recent examples on how social media has been influencing society and gives an outlook on future challenges when it comes to the design, implementation, evaluation, deployment and usage of social media.

2

History of Social Media

The 1980ies and 1990ies

The foundations for social media come from many fields, with, from a technological viewpoint, human-computer interaction its most central one. In the 1980s HCI focused a lot on how to allow people to interact efficiently and easily with computers, most often for individual users with one machine and followed by the support of users to communicate and interact in groups. Main forms of interaction styles at that time were of course textual, as in command line interfaces, and the first versions of graphical user interfaces like Apple's Lisa [27]. While history typically associates these early years of social communication as business-driven mainly operating on text and direct e-mail communication, there were already large communities using even basic text-based command-line interfaces to play games and develop games as groups. Games like [START_REF] Bartle | Hearts, Clubs, Diamonds, Spades: Players who suit MUDS[END_REF].

When it comes to how people communicated and shared information in terms of business as well as entertainment, most available channels were limited in reach (e.g. within an institution or group) and limited access was rather the norm. With the introduction of the world wide web (WWW) and its basic protocols HTML, URL and HTTP it became possible to provide information for a global audience. In 1993 there were about 50 https webservers worldwide, with about 700 websites available, ranging from the music television channel MTV to local news from the university at MIT. Most websites at that time could be found within universities. 3The commercialization of the WWW started in 1996, with an exponential growth in available websites and from 1998 to 2001 the dot.com boost. The main turning point for social media was the introduction of the Web 2.0, with its aim to allow new forms of sharing and exchanging content [START_REF]History of the WWW[END_REF].

Web 2.0 as the foundation of Social Media and its uptake

As Wikipedia summarizes, [23] most commonly, social media is understood to be interactive computer-mediated technologies that facilitate the creation or sharing of information, ideas, career interests and other forms of expression via virtual communities and networks. The common point for most of them in terms of technology is that they are based on the web 2.0, and use related protocols to distribute, share and display information on a broad variety of devices, including mobile phones.

As Figure 1 shows, the rise of social media started with the introduction of services like MSN, ebay and google. Similar services started in Asia like Baido or Tencent. With the introduction of Facebook, LinkedIn, YouTube, Twitter and Skype, five key social media channels were established that today are still amongst the top 10 used services. Figure 1 shows the introduction of similar services for Asia. With the addition of Whatsapp, Snapchat and Instagram around 2010, the major social media channels for worldwide usage had been established.

Social Media becoming an integral part of people's daily lives (2010 -2020)

In 2010 social media had around 1 billion active users, and within the past 10 years, this tripled to about 3 billion active social media users in 2020 [START_REF]Social Media Usage Statistics[END_REF]. The major social media companies Facebook, Twitter, LinkedIn and Youtube were accompanied by Snapchat with about 1 million daily active users in 2012. A broad range of other services have since then reached these milestones of more than 1 million active daily users, including Pinterest, Reddit, Tumblr, Medium, Flickr or Twitch. One of the latest social media platforms that was added to the mix is TikToc, founded in 2016, and since then the app was downloaded worldwide more than 2 billion times. Not all social media applications introduced in the last 10 years have been successful. One of the most prominent ones is Google + which disappeared most likely due to the privacy issues the platform had experienced.

From a non-US and European perspective there is a range of services that reach millions and billions of people in other parts of the world. For example, in China WeChat reaches about 1.2 billion and Tencent QQ has a user base of more than 650 million. In Korea, platforms like Kakaotalk is currently having more users than Facebook has in Korea.

The prediction for social media usage is that the growth trend will continue at least at the same pace. It has thus become unlikely that social media will disappear. On the contrary, social media will become an integral component when it comes to how society develops in the next 10 years.

3

Social Media in 2020: A Systemic Change Perspective

The Systemic Change Approach POISE

The POISE systemic change framework describes the relationship of People, Organization, Interactive System and Environment (Figure 2). The development of social media can be described using three relations (Figure 2, [START_REF] Ragosta | Concept Maps for Integrating Modeling Techniques for the Analysis and Re-Design of Partly-Autonomous Interactive Systems[END_REF]) analyzing and describing how social media has developed from supporting activities from personal and group related perspective to all activities within organizations, companies and society in general. In the original model persons (and people) were typically considered to be trained operators with validated qualifications, but today can be seen as individual users or a group of users, performing activities and tasks while interacting with a multitude of interactive systems or the Internet of Things (IoT).

Interactive systems are usually computer-based ones which present a certain level of automation and are supposed to fulfill requirements that enable users to perform activities and tasks. The computer will "disappear" in the future in the sense that it will be invisibly integrated in the physical system with which the human interacts, going even beyond the current IoT related interaction concepts.

The organization is usually a large entity composed of several organizational layers and can be extended to depict society in general. Furthermore, the organization deals with the context and the environment into which it is embedded.

The people node in Figure 2 includes aspects like the study of the human using and interacting with the system and what activities they perform when interacting with social media. The edge between people and organization/society typically is about learning and training about social media usage, its advantages and limitations. The node on organization/society includes the description of (business) processed and regulations, while the edge interactive system/organization is central for any engineering requirements of the system. The interactive system node includes all technological aspects ranging from network, to system design, and finally the edge of interactive system and people is central for how users can interact with the system and to what degree such systems enable and support users by introducing automation.

User vs System à Automation

Social media in the first place is an interaction of a user with an (interactive) system. The goal of the social media user is to perform an activity or to accomplish a task, be it to communicate, to inform, to educate or to be entertained. Tasks and activities range from a simple and specific activity like sending a text message to trying to change their mood by being entertained in general during a Sunday afternoon.

The overall experience a user has when interacting with social media is influenced by a range of software qualities including usability [11], user experience with subdimensions like aesthetics, emotion, meaning/value, social connectedness, identification or stimulation [START_REF] Bernhaupt | Evaluating user experience for interactive television: towards the development of a domain-specific user experience questionnaire[END_REF], or privacy, security and service quality.

A key aspect when it comes to the social media experience is the relation between system and user, and what tasks and activities are automated: what activities and functions can be performed by the user? What type of information is visible and transparent to the user and what things are done automatically by the system, like personalization or recommendations the system proposes? What data is automatically collected and what can be influenced by the user? When it comes to the design of a social media app, the degree of automation influences how the service will be perceived by the user in terms of usability and user experience, but more critically also in terms of privacy or service quality.

Usability & User Experience: Examples of such automation common in real applications are recommendation engines for targeted advertisement used by google or amazon. Once you have been buying a Christmas present for your parents, the system is still recommending similar articles, related to that present, even if you personally would not be interested in them. Another example is the repetition of a product advertisement that you have been buying recently, with the possible downside that the advertisement might indicate the product you have bought at a discounted price. Being offered the product you were buying with a 40% lower price can heavily influence the brand perception you have of a store or company.

Privacy:

The perception of the user to what extent their personal data is handled with the specific service (and connected to other services) with regards to automation. As example, Apple's iPhone does not allow a user to deactivate the transfer of location information of the device [START_REF]Apples Location Tracking[END_REF]. This shows how central the automation aspects are for the overall perception of privacy.

Service Quality: The 'filter bubble' originally coined by Pariser [START_REF] Pariser | The filter bubble: What the Internet is hiding from you[END_REF], describes the phenomenon that algorithms used for personalization of content can lead to an effect that a person only receives content that is similar to previous visited or selected content, thus creating a bubble around a user. This has recently become a central discussion for Facebook and the claim that Facebook is spreading fake news. The role of automation in filter bubbles is based on the algorithm implementation. The way users are interacting with the system can also play a central role [START_REF] Seargeant | Social media and the future of open debate: A user-oriented approach to Facebook's filter bubble conundrum[END_REF].

System vs Organization à Requirements

For social media to be successful a key component is the functionality different services and applications offer. When it comes to the interactive system, it is not only about the user's perspective on what is automated, but how what type of data is presented and used when it comes to different perspectives, like the organizational view. The need of an organization or company for example will be to use social media and the data generated with it, to track with as much detail as possible what and how users are interacting with their system, while on a personal basis the individual users might prefer that less personal relevant information is made available. Requirements for social media applications are thus key when it comes to the implementation aspects of the different software qualities, and how to balance between them. Will it be more beneficial to enhance the overall user experience by personalizing the service for the user by using location information of the smart phone, or is it more important to ensure the users privacy? Is it more important to have a better word completion prediction using the users movement and holding patterns of a remote control to identify the user, or do we respect the security and privacy concerns of the user, and expect that such data might be mis-used by an insurance company, say, as it allows it to predict early detection of specific diseases [START_REF] Bernhaupt | Authenticating the TV User by Biometric Continuous Measurements[END_REF].

Key aspects when it comes to requirements for social media are transparency and how to enable and ensure transparency [START_REF] Matei | Transparency in social media[END_REF], and privacy (from a technical perspective), the use, for example, of differential privacy algorithms and aspects like security, reliability or dependability. What will be central in the coming years is not how to solve each of these challenges, but how to address multi-properties and balance them [START_REF] Palanque | Beyond usability for safety critical systems: how to be sure (safe, usable, reliable, and evolvable)?[END_REF]. Is it more important to have a good user experience, or is a focus on privacy more important? Is it necessary or worth it to focus on dependability to ensure social media will not influence ongoing elections?

Or do we allow the users (and society) to handle the balancing? And simply teach and train the users, instead of solving it from a technical perspective?

People vs Organization à Learning/Training

Computer Supported Collaborative Work (CSCW) is focusing on how to design and develop technologies to support groups of users, and how interactive digital systems affect work. On a more general level, there are entire research fields focusing on how digital media and social media are influencing communication, education, entertainment and business in general.

The third angle of the system change framework is focusing on what aspects we should be focusing on when it comes to learning and training people and how to interact with social media. This can range from simple education on how to use e-banking systems for the elderly to ensure that there will be no digital gap in society, to higher level goals, on how to develop regulations to ensure social media providers are reactive enough when it comes to hate speech, fake news or country-depending un-appropriate content (for example the German NetzDG).

For the next 10 years, recent developments including some country-wide lockdowns will shift the focus even more on the necessity to understand the role of social media when it comes to society in general and how for example to enhance resilience of citizens. Recent events including the Covid 19 pandemic, for example, have already been bringing a considerable shift in the perception of how entertainment like social media entertainment and games can be highly beneficial when it comes to coping strategies, and a deeper understanding will be of profound interest when it comes to societal strategies ranging from architecture (work and life at home vs. office work) to transport (cars currently are considered safer than trains, contrary to goals we might have when it comes to sustainability).

Using the POISE Framework as Analysis Guideline for Systemic Change

The POISE framework and its three defining edges can be a guiding framework when it comes to the analysis of social media and its societal impact on a systemic change level. The POISE model should be a guide, where the components like learning, requirements, processes or automation aspects are not individual, but they are interwoven and dependent on each other. The balance between these aspects allows to balance between the different software qualities that should be achieved for the social media systems and services. The POISE model has the advantage that it encompasses the micromesa-macro approaches of systemic change approaches.

Social Media Changing Society: A Twitter Case Study

Twitter, the micro blogging and social media service, started in 2007. Users typically send short text messages called tweets to each other. These tweets initially were maximum 140 letters, and today have up to 280 letters. Twitter is commonly used for information sharing, it is a key medium for companies, businesses and people in politics and entertainment to accompany their social media strategies. There is a number of statistics that can help understand this type of social media. Among the top 50 persons with most followers are former President Obama, Ellen DeGeneres and a number of other people in entertainment like Justin Bieber or Katy Perry. From a content perspective the 20 tweets that were most shared belong to President Obama, with the Korean pop boyband BTS having 10 most shared tweets among these 20. The majority of the 20 most shared tweets is from 2020. The tweet with the most received likes in 24 hours is again from BTS (June 2020).

Twitter and twitter activities today are not only related to marketing, information sharing or public complaints. There are groupings within followers structures that are influencing societal events. In June 2020, the followers of the BTS called ARMY have been actively spamming a number of accounts to support the activities of the Black-Lives-Matters Campaign [8] by spamming accounts with BTS memes. This is a central example how political activism and influences have changed from traditional media and geographical influence to social media with international activism in a US election campaign. A possible explanation of the strength of these kpop twitter followers is that their interaction ration compared to number of followers is extremely high [9].

A second example for such activity from June 2020 is the reservation of tickets for Trumps election campaign which was disturbed by Twitter activists and TikToc users [16]. The goal of the campaign was to have (in most cases teenagers) reserve tickets for a campaign event in Tulsa, and then not using them. The strategy was very successful and even acknowledged by the Trump election campaign team.

These examples lead us back to our Dutch couple and Emma, who was surprised that her understanding of politics was better than her parents. Today social media enables very different user groups to access information worldwide, shifting traditional media approaches and campaigns to new ways of outreach and influence for society on a more general basis.

Conclusion and Future Challenges

The goal of this chapter was to give a brief overview of social media history, and to show how the impact of social media can be analyzed using the POISE framework. The POISE framework connects traditional computer science-oriented approaches and theories based on socio-technical systems with the potential to address social media influence on the larger societal level. This chapter was written in times of change and, given the current drastic changes in society, it becomes clear that, in the foreseeable future, social media will become an integral part of our daily lives, given the necessity to connect and socialize more digitally and virtually than through personal contact. Since the introduction of social media and its rise since 1995 digitalization has changed the world. Figure 3 shows a comparison of the impact of such trends using the Pope as an example. While in 2005 usage of smart phones was very limited, the pictures for 2013 speak a different language, showing the uptake of social media. Today the pope is having the most influential twitter account in the religious world (@Pontifex, @Pon-tifex_es and @Pontifex_it), and as the picture in Figure 3 right-side shows, this has become key to reach followers, given the limitations in personal interaction in 2020. Future challenges will be the design and development of interactive systems and more general social-technical systems and services that allow the integration of different social media channels with existing systems to lay a basis for next generation services based on cross-usages of IoT based infrastructures. ICT professionals, both researchers and practitioners, and professional societies must contribute to a responsible development and implementation of such technologies and services.

Fig. 1 .

 1 Fig. 1. Overview of social media applications, platforms and services from 1995 onwards [28]

Fig. 2 .

 2 Fig. 2. The POISE Research Framework for People, Organization, Interactive System and Environment extends a standard socio-technical system model from the 1960ies [6]

Fig. 3 .

 3 Fig. 3. Demonstration of changes in the last 15 years following the Pope with audiences in 2005, 2013 and without audience in 2020

BLINK fans following and supporting the Korean Pop group Blackpink[START_REF] Blackpink | [END_REF], ARMY fans following and supporting the Korean Pop Group BTS[7]

2 Shipping: initially derived from the word relationship, is the desire by fans for two or more people, either real-life people or fictional characters (in film, literature, television, etc.) to be in a romantic relationship [21].

Personal note: I would like to take this opportunity to apologize to the course instructor of networks and distributed systems in my computer science education in 1995, asking us to set-up our own personal website. I commented, it was useless time spent having a personal website. He was right, I was wrong.


Sandrine Marchand

Denis Frasca

Claire Dahyot-Fizelier

Céline Breheret

Olivier Mimoz

William Couet
email: william.couet@univ-poitiers.fr

William Pr

Couet

Lung Microdialysis Study of Levofloxacin in Rats following Intravenous Infusion at Steady-State Running Title: Microdialysis study of levofloxacin in lung

A microdialysis distribution study of levofloxacin in the lung and muscle of rats was conducted from a single point determination after intravenous infusion at steady-state. This approach was presented as an interesting alternative to investigate antibiotics tissue distribution.

Several different methodological approaches are available to asses the distribution of antibiotics in the lung of animals or patients [START_REF] Kiem | Interpretation of antibiotic concentration ratios measured in epithelial lining fluid[END_REF]. It is now recognized that drug concentrations in whole tissue homogenates are difficult to interpret and therefore not informative [START_REF] Mouton | Tissue concentrations: do we ever learn?[END_REF]. In human the most popular experimental approach to characterize antibiotics distribution in lungs relies on bronchoalveolar lavages (BAL) [START_REF] Conte | Intrapulmonary pharmacokinetics and pharmacodynamics of meropenem[END_REF][START_REF] Conte | Intrapulmonary pharmacokinetics and pharmacodynamics of high-dose levofloxacin in healthy volunteer subjects[END_REF][START_REF] Conte | Intrapulmonary pharmacodynamics of high-dose levofloxacin in subjects with 12 chronic bronchitis or chronic obstructive pulmonary disease[END_REF] and micro-BAL was recently proposed [START_REF] Boselli | Reliability of mini-bronchoalveolar lavage for the measurement of epithelial lining fluid concentrations of tobramycin in critically ill patients[END_REF]. Microdialysis is an appealing technique that was increasingly used over the last years to investigate antibiotics distribution in the extracellular fluid (ECF) of various tissues including lung, both in rats and humans [START_REF] Dahyot | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of Acinetobacter baumannii-infected rats[END_REF][START_REF] Hutschala | In vivo measurement of levofloxacin penetration into lung tissue after cardiac surgery[END_REF][START_REF] Liu | Interstitial tissue concentrations of cefpodoxime[END_REF][START_REF] Marchand | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of noninfected rats[END_REF][START_REF] De La Peña | Penetration of cefaclor into the interstitial space fluid of skeletal muscle and lung tissue in rats[END_REF][START_REF] Zeitlinger | Lung microdialysis--a powerful tool for the determination of exogenous and endogenous compounds in the lower respiratory tract[END_REF]. One of the major advantages of microdialysis over BAL or micro-BAL is that it allows multiple determinations in the same subject and therefore full description of the drug concentrations versus time profile following its administration. However in human lung microdialysis studies are limited to patients with elective thoracic surgery and in rats they require maintenance of the animal anaesthetized with open chest surgery [START_REF] Dahyot | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of Acinetobacter baumannii-infected rats[END_REF][START_REF] Marchand | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of noninfected rats[END_REF]. As a consequence for antibiotics with long elimination halflives, it may be difficult to maintain study duration for a period of time long enough to properly characterize major pharmacokinetic parameters such as total drug concentrations versus time area under curves (AUCs). Comparison of total unbound AUCs in lung ECF and plasma may provide important information such as indirect evidence for the involvement of active efflux transport systems [START_REF] Dahyot | Application of basic pharmacokinetic concepts to analysis of microdialysis data: Illustration with imipenem muscle distribution[END_REF]. These systems, including Pglycoprotein (P-gp), are present in brain and are responsible for lower unbound AUCs in brain ECF than in plasma as previously demonstrated with several anti-infectious drugs using microdialysis [START_REF] Edwards | GF120918, A Pglycoprotein modulator, increases the concentration of unbound amprenavir in the central nervous system in rats[END_REF][START_REF] Granero | Analysis of ceftriaxone and ceftazidime distribution in cerebrospinal fluid of and cerebral extracellular space in awake rats by in vivo microdialysis[END_REF][START_REF] De Lange | In vitro and in vivo investigations on fluoroquinolones; effects of the P-glycoprotein efflux transporter on brain distribution of sparfloxacin[END_REF][START_REF] Marchand | Dose ranging pharmacokinetics and brain distribution of norfloxacin using microdialysis in rats[END_REF]. The presence of P-gp in lung is suspected [START_REF] Endter | P-glycoprotein (MDR1) functional activity in human alveolar epithelial cell monolayers[END_REF][START_REF] Leslie | Multidrug resistance proteins: role of P-glycoprotein, MRP1, MRP2, and BCRP (ABCG2) in tissue defense[END_REF][START_REF] Scheffer | Multidrug resistance related molecules in human and murine lung[END_REF][START_REF] Steimer | Monolayers of porcine alveolar epithelial cells in primary culture as an in vitro model for drug absorption studies[END_REF] and therefore potentially responsible for restricted drug tissue distribution, although this has never been documented, at least to our knowledge. In order to do that it should be possible to compare total unbound AUCs in lung tissue ECF and plasma following single dose administration, but interestingly comparing unbound drug concentrations following intravenous infusion at steady-state would provide exactly the same information [START_REF] Dahyot | Application of basic pharmacokinetic concepts to analysis of microdialysis data: Illustration with imipenem muscle distribution[END_REF]. The advantage of steady-state conditions is to require a single concentration determination in plasma and tissue, which is much more simple and probably more accurate than determining AUCs after single dose administration. The feasibility and optimization of such an alternative approach is now being tested using levofloxacin (LVX) as a representative antibiotic.

Experiments were done in accordance with the Principles of Laboratory Animals Care (NIH Publication #85-23, revised 1985) using male Sprague Dawley rats (Janvier Laboratories, Le Genest-St-Isle, France), weighing 316 ± 49 g. The day before experiments (D-1), between 9:00 pm and 11:00 am, rats were anesthetized with airisoflurane mixture and equipped with a vein femoral catheter for LVX administration and with microdialysis CMA/20 probes (polycarbonate, cutoff 20000 Da, membrane length 10 mm, CMA microdialysis, Phymep, Paris, France) in blood and muscle for drug concentrations determinations, as previously described [START_REF] Marchand | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of noninfected rats[END_REF]. After rats wake up and six to seven hours post surgery, infusion of a commercial solution of LVX (5 mg.mL -1 , Sanofi Aventis, Paris, France) was started at a rate of 1.0 mg.h -1 , maintained overnight to reach steady-state and until the end of experiment. On the morning of day zero (D0) rats were anesthetized, tracheotomized, mechanically ventilated and torachotomized for lung microdialysis probe insertion (LMP 5.35.35, polyether sulfone, cut off: 6000 Da, membrane length: 10mm, outer diameter: 0.6 mm, Microbiotech, Stockholm, Sweden) as previously described [START_REF] Marchand | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of noninfected rats[END_REF]. Probes recoveries were estimated by the retrodialysis by calibrator method. A solution of ciprofloxacin (CIP) (2 µg.mL -1 ) was perfused into the three probes at a flow rate of 2 µL.min -1 for 15 min. A flow rate equal to 0.5 µL.min -1 was then maintained for 60 min before starting dialysates collection, and until the end of the experiment. Dialysates were collected from blood, muscle and lung probes every 45 min over 270 min, corresponding to 6 samples. The relative recovery by loss of the calibrator (CIP) was calculated for each interval of collect according to the following equation: RL CIP = (Cin -Cout)/ Cin, where Cin and Cout correspond to the CIP concentrations in perfusate and in dialysates collected. Actual LVX concentrations were estimated by correcting measured concentrations in dialysates by the recovery by loss of CIP determined during the same interval of collect. For each rat and medium ECF concentrations at steady-state are presented as a mean ± S.D value derived from the 6 consecutive determinations. The in vitro recoveries by gain and by loss of CIP and LVX were evaluated from three probes (two CMA 20 probes and one linear probe) during 240 min at a flow rate of 1 µL.min -1 and concentrations equal to 3 µg.mL -1 . In vivo recoveries by loss of CIP and LVX were compared in 3 dedicated rats: A, B and C. A mixture of the 2 compounds, each at a concentration of 2 µg.mL -1 , was perfused in each probe at a flow rate of 0.5 µL.min -1 during 270 min and dialysates were collected by fractions every 45 min. Simultaneous analyse of LVX and CIP in dialysates were performed by HPLC as previously described [START_REF] Marchand | Dose ranging pharmacokinetics and brain distribution of norfloxacin using microdialysis in rats[END_REF]. Dialysates were injected directly after dilution in phosphate buffer (pH=7) (1/1, vol/vol). Both compounds were analyzed at the same wavelengths: λex=285 nm, λem=490 nm. The between-day variability of the assay was characterized each day of the analysis and was respectively less than 20% and 10% at two concentrations levels (0.125 and 1 µg.mL -1 ).

Steady-state conditions preclude the retrodialysis by drug method to estimate probes recoveries, and considering that our objective was to conduct an experiment within a limited period of time, the retrodialysis by calibrator method was the best method for that. CIP had been previously validated as an appropriate calibrator for another fluoroquinolone antibiotic, norfloxacin (NOR) [START_REF] Marchand | Dose ranging pharmacokinetics and brain distribution of norfloxacin using microdialysis in rats[END_REF]. It was therefore tested again as a potential calibrator for LVX. In vitro recoveries by gain and by loss of CIP and LVX were not statistically different (data not shown). Differences between LVX and CIP in vivo recoveries by loss in blood, muscle and lung, were always lower than 7%, with only an exception for Rat C in lung (Table 1).

Individual values of CIP recoveries by loss determined in rats receiving LVX (Rats 1-8) are presented in Table 2. These values were generally consistent with those obtained during the validation phase (Rats A-C), although relatively higher recoveries were occasionally observed especially in blood. Recovery by loss of CIP in lung was 3 to 4 folds lower on average than in muscle or blood (Table 2), again consistent with observations made in Rats A-C, as well as with previous experiments [START_REF] Dahyot | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of Acinetobacter baumannii-infected rats[END_REF][START_REF] Marchand | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of noninfected rats[END_REF]. These relatively low recoveries in lung are most likely due to the different nature and cut-off of the membrane compared to CMA/20 probes. The between rats variability in lung probes recoveries, with extreme values ranging between 9.2 ± 3.6% and 31.5 ± 7.5% was also larger than in other media (Table 2). Altogether these data suggest that CIP may be considered as an appropriate calibrator for LVX, although discrepancies between the estimated recovery by loss of the calibrator and the actual recovery of the tested compound may occasionally occur, especially in lung, possibly leading to outliers values in the estimated LVX concentrations.

Individual steady-state unbound concentrations of LVX in each medium are presented on Figure 1. The between rats as well as the between medium variability was rather limited and average unbound steady-state concentrations in the various rats and medium compared favorably with only one exception (lung data in Rat 3). Errors bars corresponding to standard deviations associated to these estimated average concentrations (n=6) were most often higher in lung than in other medium, illustrating the greater uncertainty on concentrations estimates in this tissue compared to plasma or muscle. This observation which is again consistent with previous findings [START_REF] Dahyot | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of Acinetobacter baumannii-infected rats[END_REF][START_REF] Marchand | Microdialysis study of imipenem distribution in skeletal muscle and lung extracellular fluids of noninfected rats[END_REF] is probably a consequence of the lower lung probes recoveries. Because flow rate was already quite low (0.5 µL.min -1 ), it does not seem possible to substantially increase lung probes recoveries by further reducing the flow. Using different probes with increased recovery should potentially be of greater benefit. ECF steady-state unbound tissue to blood concentrations ratios were respectively equal to 1.00 ± 0.15 in muscle and 1.06 ± 0.40 in lung, suggesting passive tissue distribution of LVX [START_REF] Dahyot | Application of basic pharmacokinetic concepts to analysis of microdialysis data: Illustration with imipenem muscle distribution[END_REF]. These values are in partial agreement with data previously obtained in human and published mostly by researchers from the same group [START_REF] Bellmann | Tissue pharmacokinetics of levofloxacin in human soft tissue infections[END_REF][START_REF] Hutschala | In vivo measurement of levofloxacin penetration into lung tissue after cardiac surgery[END_REF][START_REF] Zeitlinger | Relevance of soft-tissue penetration by levofloxacin for target site bacterial killing in patients with sepsis[END_REF][START_REF] Zeitlinger | A pilot study testing whether concentrations of levofloxacin in interstitial space fluid of soft tissues may serve[END_REF]. The first LVX microdialysis distribution study in human was conducted in the skeletal muscle tissue of patients with sepsis [START_REF] Zeitlinger | Relevance of soft-tissue penetration by levofloxacin for target site bacterial killing in patients with sepsis[END_REF]. Unbound plasma concentrations were derived from measured total plasma concentrations assuming an average fraction bound equal to 35%. Ratio of the tissue to plasma unbound AUCs from time 0 to 8h (AUC 0-8 ) was used to characterize LVX distribution and was estimated to 0.85. The second study was conducted in subcutaneous adipose tissue using similar procedure, except that AUCs were estimated from time 0 to 10h and plasma protein binding was assumed to be equal to 25% [START_REF] Bellmann | Tissue pharmacokinetics of levofloxacin in human soft tissue infections[END_REF].

Average tissue to plasma unbound AUCs ratios were again close to unity (1.1 ± 0.6 for healthy and 1.2 ± 1.0 for inflamed subcutaneous adipose tissue). The third article describes the first microdialysis distribution study in lung [START_REF] Hutschala | In vivo measurement of levofloxacin penetration into lung tissue after cardiac surgery[END_REF] and lead to the conclusion that LVX penetration in this tissue was lower than in muscle [START_REF] Zeitlinger | Relevance of soft-tissue penetration by levofloxacin for target site bacterial killing in patients with sepsis[END_REF] or subcutaneous adipose tissue [START_REF] Bellmann | Tissue pharmacokinetics of levofloxacin in human soft tissue infections[END_REF]. However in this study unbound AUCs of LVX in lung were compared to total plasma AUCs, with a mean ratio equal to 0.6. Therefore after correcting plasma AUC for protein binding as previously done by these authors, and considering that 30% of LVX is bound in plasma, one would obtain a mean tissue to plasma unbound AUCs ratio equal to 1.9, that is actually higher than the previously reported values close to unity [START_REF] Bellmann | Tissue pharmacokinetics of levofloxacin in human soft tissue infections[END_REF][START_REF] Zeitlinger | Relevance of soft-tissue penetration by levofloxacin for target site bacterial killing in patients with sepsis[END_REF]. The last study was then conducted to clarify the apparently conflicting data between muscle or subcutaneous tissue and lung [START_REF] Zeitlinger | A pilot study testing whether concentrations of levofloxacin in interstitial space fluid of soft tissues may serve[END_REF]. Unfortunately distinct subjects were enrolled in the study with muscle and subcutaneous distribution being investigated in healthy volunteers and lung distribution in patients undergoing elective lung surgery.

Furthermore unbound tissue concentrations determined by microdialysis were again compared with total plasma concentrations making AUCs ratios interpretation difficult, especially since LVX plasma protein binding may vary between healthy volunteers and patients. But interestingly in this last study total AUCs were used to characterize LVX tissue distribution. Unfortunately microdialysate samples were collected over a 8 h period of time, which considering the delayed peak in tissue (between 1h and 3h) and the relatively long elimination half-life of LVX (estimated to 5-6h in this study), does not allow precise estimation of total AUCs. This study lead to the conclusion that LVX levels in the ECF of soft tissues cannot serve as a surrogate for predicting its pharmacokinetics in lung [START_REF] Zeitlinger | A pilot study testing whether concentrations of levofloxacin in interstitial space fluid of soft tissues may serve[END_REF], whereas the results of our study that was conducted in rats but measuring LVX concentrations in both tissues of each animal, suggest the opposite.

Microdialysis tissue distribution studies following single doses administrations should rely on the comparison between total unbound AUCs in tissue and plasma [START_REF] Dahyot | Application of basic pharmacokinetic concepts to analysis of microdialysis data: Illustration with imipenem muscle distribution[END_REF], but as exemplified by this series of studies conducted with LVX this is not always done, and it may be difficult to accurately estimate these total AUCs. On many occasions AUCs between two consecutive administrations at steady-state should be equal to total AUCs after single doses, but they may not be more practical to estimate. Therefore comparison of tissue ECF and plasma unbound concentrations following intravenous infusion at steady-state appears as an interesting alternative to characterize drug tissue distribution, in particular to look for active efflux transport phenomenon. Although a single concentration measurement in tissue and plasma would be enough from a theoretical standpoint, six consecutive series of determinations were conducted for this initial study. Yet this was without major benefit since these individual values were always consistent and the number of determinations should be reduced for the next studies. Yet as opposed to microdialysis studies conducted with multiple drug determinations after single dose administrations, the major limitation of this proposed approach based on single points as a surrogate for predicting its pharmacokinetics in lung. Int. J. Antimicrob.

Agents. 29 : 44-50.

TABLE 1 .

 1 In vivo recoveries by loss of CIP and LVX (mean ± SD, n=6) perfused as a Ringer solution (CIP / LVX mixture at 2 µg.mL -1 each) at a flow rate of 0.5 µL.min-1 during 270 min, in the blood, muscle and lung probes of 3 rats (A-C)

		In vivo recoveries by loss (%) (n=6)
		Blood	muscle	Lung
	LVX	43.6 ± 5.6	38.9 ± 1.7	11.4 ± 3.8
	Rat A
	CIP	42.9 ± 5.9	35.9 ± 1.5	11.3 ± 3.8
	LVX	48.0 ± 3.0	36.8 ± 0.7	12.8 ± 3.0
	Rat B
	CIP	49.1 ± 3.1	36.1 ± 1.8	10.9 ± 4.0
	LVX	51.0 ± 2.1	36.1 ± 3.9	6.9 ± 2.4
	Rat C
	CIP	56.6 ± 2.0	39.1 ± 4.4	11.9 ± 2.4

TABLE 2 .

 2 In vivo recoveries by loss of CIP (mean ± SD, n=6) perfused as a Ringer solution (2 µg.mL -1 , 0.5 µL.min -1 ) in the blood, muscle and lung probes of 8 rats receiving an intravenous infusion of LVX (1.0 mg.h -1 ) at steady state .

		CIP in vivo recoveries by loss (n=6)
		blood	muscle	lung
	Rat 1	44.6 ± 3.1	45.0 ± 3.9	31.5 ± 7.5
	Rat 2	41.0 ± 3.6	38.4 ± 4.4	9.4 ± 2.5
	Rat3	32.6 ± 2.2	48.4 ± 2.9	22.8 ± 10.0
	Rat 4	74.6 ± 1.1	30.8 ± 1.4	18.8 ± 3.5
	Rat 5	38.4 ± 1.1	45.0 ± 1.4	10.4 ± 3.3
	Rat 6	46.3 ± 4.3	46.6 ± 2.4	12.1 ± 8.2
	Rat 7	73.4 ± 1.2	48.5 ± 1.7	15.9 ± 3.9
	Rat 8	73.4 ± 1.3	48.5 ± 1.8	15.9 ± 3.1

Rat 2 Rat 3 Rat 4 Rat 5 Rat 6 Rat 7 Rat 8 Levofloxacin unbound steady state concentrations (µg.mL -1 ) muscle blood lung Rat 1 Rat 2 Rat 3 Rat 4 Rat 5 Rat 6 Rat 7 Rat 8 Levofloxacin unbound steady state concentrations (µg.mL -1 ) muscle blood lung

determination at steady-state, is that it does not provide any information on the tissue rate of distribution, that can be modified in the presence of various patho-physiological conditions such as altered blood flow.

In conclusion lung microdialysis investigations following drug infusion at steady-state appear as an interesting alternative to the same type of experiments conducted after single dose administration for the characterization of lung distribution of antibiotics.