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Denna kandidatuppsats undersöker de olika diskurser angående det övernaturliga som närvarar i Eden Robinsons roman Monkey Beach (2000) utifrån ett postkolonialt perspektiv. Det teoretiska ramverket består av Jo-Ann Episkenews indigenous storytelling, samt Michail Bachtins dialogicitetsbegrepp, där heteroglossi fungerar som utgångspunkt. Dessa har använts för att analysera hur Robinson använder sig av karaktärer för att gestalta olika epistemologier, och hur dessa relaterar till synen på det övernaturliga i romanen. Uppsatsens slutsats är att Monkey Beach är polyfon i sin gestaltning av de olika perspektiven på det övernaturliga; dessa perspektiv utgör olika diskurser, vilket gestaltas genom karaktärerna. Romanen utspelar sig inte i ett autonomt fiktivt universum; den fungerar som en motdiskurs till tidigare diskurser om urfolk i Kanada, vilket ger den både en avkoloniserande och kunskapsspridande funktion då den är skriven av en urfolksförfattare. / This undergraduate dissertation examines the various discourses surrounding the supernatural present in Eden Robinson’s novel Monkey Beach (2000) from a postcolonial perspective. The theoretical framework consists of Jo-Ann Episkenew’s Indigenous Storytelling, as well as Michail Bachtin’s concept of dialogism, with heteroglossia as its basis. These have been applied to the text to analyse how Robinson utilises characters to depict different epistemologies, and how they relate to the portrayal of the supernatural in the novel. The conclusion of this dissertation is that Monkey Beach is polyphonic in its portrayal of the various perspectives of the supernatural; these perspectives constitute different discourses, which are depicted through the characters. The novel does not take place in an autonomous fictional universe; it functions as a counter-discourse to previous discourses about Indigenous peoples in Canada, which gives it a decolonising and knowledge-disseminating function as it is written by an Indigenous author.

Im Jahre 1958, schlug Kenneth W. Robinson die Nutzung eines Korrektormagneten vor um den entdämpften radialen Betatronoszillationen im Cambridge electron accelerator entgegen zu wirken. Dieser Korrektormagnet sollte aus kurzen, alternierenden Dipolen mit einem starken Gradienten bestehen, sodass die Verluste durch Synchrotronstrahlung mit zunehmendem Trajektorienradius abnehmen. Diese Transversal-Gradienten-Wiggler werden auch "Robinson Wiggler" (RW) genannt. Die Metrology Light Source (MLS), welche Eigentum der Physikalisch-Technischen Bundesanstalt (PTB) ist und vom Helmholtz-Zentrum Berlin (HZB) entworfen und betrieben wird, ist ein Elektronen-Synchrotron, optimiert für die Produktion von Synchrotronstrahlung im Spektralbereich zwischen THz und EUV. Da die MLS eine gerampte Maschine ist, nimmt der gespeicherte Elektronenstrom mit der Zeit ab und die Strahllebensdauer ist von Bedeutung für die Nutzer der Synchrotronstrahlung. Es wird vorgeschlagen einen RW bei der MLS zu installieren um die Strahllebensdauer zu erhöhen. Mit RW wäre es möglich, Dämpfung aus der longitudinalen in die horizontale Ebene zu verschieben sodass sich die Energiebreite um einen Faktor 3 erhöht und die Emittanz sich um ungefähr einen Faktor 2 reduziert. Die Länge der Elektronenpakete wird dadurch stärker verlängert als die mittlere horizontale Paketbreite reduziert wird. So nimmt die Elektronendichte im Paket ab und die Verlustrate sinkt. Dies hat zu Folge dass sich die Lebensdauer verbessert und die Aktivierung von Komponenten reduziert wird. Mit erhöhter Energiebreite und verringerter Emittanz, wird der Beitrag der Dispersion zur horizontalen Quellgröße stärker. Durch geeignete Wahl der Magnetoptik kann die Brillianz am Quellpunkt erhöht werden bei gleichzeitiger Verbesserung der Lebensdauer. Simulationen zeigen dass die Lebensdauer an der MLS durch die Installation eines solchen RW um einen Faktor 2.3 ansteigt, was einem Zugewinn an integriertem Photonenfluss von 30 % entspricht. / In 1958, Kenneth W. Robinson proposed the usage of a magnetic correction device to reduce the antidamping of radial betatron oscillations in the Cambridge electron accelerator. The essence of this correction device are short, alternating dipoles with a strong gradient, such that the radiation loss decreases with increasing radius of trajectory. These transverse gradient wigglers are also called "Robinson Wigglers" (RW). The Metrology Light Source (MLS), owned by the Physikalisch-Technische Bundesanstalt (PTB) and designed and operated by Helmholtz-Zentrum Berlin (HZB), is an electron synchrotron, optimized for the production of synchrotron radiation in the THz to the EUV spectral region. Being a ramped machine, Top-Up operation is not possible. With a decaying beam current, the lifetime of the stored beam is of importance for the user community, for reasons of temporal stability and integrated photon flux. It is proposed to install a RW at the MLS in order to improve the beam lifetime. With a RW, it is possible to transfer damping from the longitundinal to the horizontal plane in a way, that the energy spread increases by a factor of 3 and the emittance reduces by a factor of 2. Doing so, the bunch length is increased by a larger fraction than the average bunch width is decreased. Thereby the electron density is reduced which results in a lower loss rate of electrons. This improves the beam lifetime and reduces induced radioactivity of accelerator components and shielding. With an increased energy spread and a reduced emittance, the contribution of the dispersion to source size becomes more important. By carefully choosing the magnet optics, the brilliance at the source point can be improved simultaneously to increasing the lifetime. Simulations indicate that a RW is able to increase the lifetime in the standard user operation mode at the MLS by a factor of 2.3, corresponding to an increase in photon flux for one standard user run of approximately 30 %.

Franz Baermann Steiner [1909-1952], à la fois poeta doctus de langue allemande et anthropologue de langue anglaise, développe dans son oeuvre une pensée qui préfigure la théorie postcoloniale, d’une part par sa critique de l’eurocentrisme, de l’impérialisme colonial et de la violence épistémique occidentale, et d’autre part, à travers son ethnopoésie et la réécriture poétique du mythe robinsonien. La présente étude s'attache à analyser le discours postcolonial dans l’ensemble de son oeuvre qui comprend plus de 9500 aphorismes, quelques 300 poèmes et des écrits scientifiques. Présentant l’arrière-plan culturel et l’identité de Steiner, qui sont comparés à ceux des intellectuels postcolonialistes, l’étude examine d’abord les éventuelles structures coloniales dans l’Empire austro-hongrois, de la situation sociopolitique en Bohême et à Prague pendant la première République Tchèque. Ainsi elle révèle les éléments structurels qui ont favorisé l’éclosion du discours postcolonial chez Steiner : la position liminale et le caractère hybride de la communauté d’origine de Steiner – les juifs pragois germanophones –, l’impact discursif du sionisme culturel, son exil en Angleterre et, enfin, son appartenance à la Social Anthropology. Ensuite, elle retrace le discours aux accents postcoloniaux, depuis son origine dans ses aphorismes, dans son oeuvre anthropologique et poétique. La liminalité, notion centrale du postcolonialisme, est omniprésente dans l’oeuvre de l’auteur tant sur le plan méthodologique [positionnement discursif contestataire ou observateur] que thématique [esclavage, tabou, poète chaman, exil]. Malgré l’attachement de l’auteur à la pensée essentialiste, l'hybridité constitue un élément essentiel de son identité, irriguant toute son oeuvre. [Traduisibilité de faits culturels, ethnopoésie hybride, figure robinsonienne hybride]. / Franz Baermann Steiner [1909-1952], an exile from Prague, was a German poeta doctus who taught anthropology at the Oxford Institute after the Second World War. In his oeuvre, comprising more than 9500 aphorisms, over 300 poems and also anthropological writings, he sketches a critique of eurocentrism, colonial imperialism and epistemic violence, thus anticipating postcolonial theory. The first part of our thesis analyses how an assimilated Jew from Prague developed a discourse that takes up notions developed in the writings of Aimé Césaire and Edward Said. It therefore offers a complete analysis of his background in the Habsburg Empire from a post-colonial point of view, and an evaluation of the linguistic and social politics in Bohemia and Prague during the first Czech Republic. The study focuses, on the one hand, on the hybrid and liminal character of his milieu [i.e. German Jews in Prague] as well as the decisive discursive impact of cultural Zionism and, on the other hand, on his exile in England and the influence of British Social Anthropology. These are, from our point of view, the key elements of the post-colonial discourse emerging in Steiner’s writings. Taking his aphorisms as a starting point, our study then follows up the post-colonial thought in the entire oeuvre of the poet and anthropologist, underlining the various links between poetry, religion and science which are so characteristic of his original writings. The concept of liminality is present in all his writings on a methodological level [a liminal discursive positioning within the Western academic structures and an observant position in his poetry] and it also dominates the choice of themes [slavery, taboo, Shaman poet and exile]. Although Steiner never completely abandoned the essentialist vision of culture, the notion of hybridity is an essential factor of his identity, enriching his writings immensely [e.g. problem of cultural translatability, hybrid ethnopoetics and a new hybrid Robinson figure].

<p>Den här studien har sitt fokus inom krimnalromangenren. Det finns två huvudlinjer. Först koncentrerar studien sig på vilka strategier två kvinnliga protagonister är tvungna att anta för att nå yrkesmässig framgång i en mansdominerad miljö. För att var mer specifik så undersöks Chief Medical Examiner Kay Scarpetta från serien om Scarpetta av Patricia Cornwell och D.S Annie Cabbot från serien om Inspector Banks av Peter Robinson och deras förhållande till auktoritet, makt, äktenskap och moderskap. Fin-de-Siècle ger den underliggande definitionen av kön genom sin skeva syn på vad som anses vara normen för kvinnlighet. Kvinnan förväntades då att centrera sin existens inom hemmets sfär som den perfekta hustrun och modern. Hon ansågs dessutom vara olämpliga för en yrkeskarriär då hennes hälsa var alltför vacklande och tänkandet dominerat av känslor snarare än förnuft.</p><p>I denna uppsats argumenteras för att spår av detta sätt att tänka om kvinnan fortfarande står att finna i de aktuella romanerna. Protagonisterna tvingas därför att öppet utmana dessa normer för att nå framgång.</p><p>I överesnstämmelse med argument presenterade av Judith Halberstam i <em>Female Masculinity</em>, ger studien dessutom exempel på hur de valda protagonisterna blir bestraffade på grund av sin ovilja att följa den etablerade normen av kvinnlighet. Bestraffningen tar sig tre uttryck: psykologiskt genom att protagonisterna kritiseras, ignoreras och undervärderas; yrkesmässigt, genom att ifrågasättas rättsligt och genom anklagelser om allvarlig inkompetens, samt fysiskt genom att bli offer för sexuella övergrepp. Eftersom protagonisterna agerar enligt de traditionella normerna finns en indikation på att dessa normer fortfarande lever.</p><p>Som slutsats anges att även om hundra år har passerat sedan fin-de-siècle och etablerandet av de könsnormer som här nämns agerar protagnisterna enligt dessa. Karakteriseringen av Scarpetta och Cabbot är dessutom beroende av den tradition som finns etablerad inom kriminalgenrenvilket begränsar uttrycket av kön. Studien föreslår att kategoriseringen av kön i två kategorier enbart: män och kvinnor, är alltför snäv och att könsdefinitionen behöver utökas. I studien framkommer att de kvinnliga protagonisterna anses vara icke-typiska kvinnor eller homosexuella genom sitt sätt att utmana den traditionella synen på kvinnlighet.</p> / <p>This study maintains a focus within the genre: crime fiction.  There are two main strands. First, there is an exploration of what strategies are adopted by two female protagonists to achieve professional success in a male dominated setting. More specifically, it investigates Chief Medical Examiner Kay Scarpetta from the Scarpetta-series by Patricia Cornwell and D.S Annie Cabbot from the Inspector Banks series by Peter Robinson and their relationship to authority, power, marriage and children. The Fin-de-Siècle provides the basis for the under-lying definition of gender through its skewed formulation of female norms. Women were to centre their existence within the domestic domain of life as perfect wives and mothers. Furthermore, they were considered unsuitable for professional commitments due to fragile health and domination of emotions over reason. In this essay it is argued that, in these novels, traces of these expectations regarding the nature of womanhood are still current and that the protagonists have to challenge these openly to reach success.</p><p>Secondly, in agreement with claims by Judith Halberstam in her work <em>Female Masculinity, </em>the study exemplifies how the selected protagonists are portrayed as punished because of their disobedience to the pre-established norm of womanhood. This punishment takes three forms: psychologically, by being devalued, criticised and ignored; professionally, by being legally questioned and accused of severe incompetence and physically by being victims of sexual assault.</p><p>The conclusion states that, in spite of a century having past since the establish-ment of the norms of womanhood referred to here, the female protagonists act accordingly which indicates that these norms are still current. Furthermore, the portrayal of Scarpetta and Cabbot is dependent on the genre in which they belong which limits the possible expression of gender. It is suggested that the gender categories: men and women are too narrow and that the definition of woman needs to be extended.Within the characterisation of the two prota-gonists in the study there is evidence that they are considered atypical women or homosexuals because of their opposing the traditional views of womanhood.</p>

Den här studien har sitt fokus inom krimnalromangenren. Det finns två huvudlinjer. Först koncentrerar studien sig på vilka strategier två kvinnliga protagonister är tvungna att anta för att nå yrkesmässig framgång i en mansdominerad miljö. För att var mer specifik så undersöks Chief Medical Examiner Kay Scarpetta från serien om Scarpetta av Patricia Cornwell och D.S Annie Cabbot från serien om Inspector Banks av Peter Robinson och deras förhållande till auktoritet, makt, äktenskap och moderskap. Fin-de-Siècle ger den underliggande definitionen av kön genom sin skeva syn på vad som anses vara normen för kvinnlighet. Kvinnan förväntades då att centrera sin existens inom hemmets sfär som den perfekta hustrun och modern. Hon ansågs dessutom vara olämpliga för en yrkeskarriär då hennes hälsa var alltför vacklande och tänkandet dominerat av känslor snarare än förnuft. I denna uppsats argumenteras för att spår av detta sätt att tänka om kvinnan fortfarande står att finna i de aktuella romanerna. Protagonisterna tvingas därför att öppet utmana dessa normer för att nå framgång. I överesnstämmelse med argument presenterade av Judith Halberstam i Female Masculinity, ger studien dessutom exempel på hur de valda protagonisterna blir bestraffade på grund av sin ovilja att följa den etablerade normen av kvinnlighet. Bestraffningen tar sig tre uttryck: psykologiskt genom att protagonisterna kritiseras, ignoreras och undervärderas; yrkesmässigt, genom att ifrågasättas rättsligt och genom anklagelser om allvarlig inkompetens, samt fysiskt genom att bli offer för sexuella övergrepp. Eftersom protagonisterna agerar enligt de traditionella normerna finns en indikation på att dessa normer fortfarande lever. Som slutsats anges att även om hundra år har passerat sedan fin-de-siècle och etablerandet av de könsnormer som här nämns agerar protagnisterna enligt dessa. Karakteriseringen av Scarpetta och Cabbot är dessutom beroende av den tradition som finns etablerad inom kriminalgenrenvilket begränsar uttrycket av kön. Studien föreslår att kategoriseringen av kön i två kategorier enbart: män och kvinnor, är alltför snäv och att könsdefinitionen behöver utökas. I studien framkommer att de kvinnliga protagonisterna anses vara icke-typiska kvinnor eller homosexuella genom sitt sätt att utmana den traditionella synen på kvinnlighet. / This study maintains a focus within the genre: crime fiction.  There are two main strands. First, there is an exploration of what strategies are adopted by two female protagonists to achieve professional success in a male dominated setting. More specifically, it investigates Chief Medical Examiner Kay Scarpetta from the Scarpetta-series by Patricia Cornwell and D.S Annie Cabbot from the Inspector Banks series by Peter Robinson and their relationship to authority, power, marriage and children. The Fin-de-Siècle provides the basis for the under-lying definition of gender through its skewed formulation of female norms. Women were to centre their existence within the domestic domain of life as perfect wives and mothers. Furthermore, they were considered unsuitable for professional commitments due to fragile health and domination of emotions over reason. In this essay it is argued that, in these novels, traces of these expectations regarding the nature of womanhood are still current and that the protagonists have to challenge these openly to reach success. Secondly, in agreement with claims by Judith Halberstam in her work Female Masculinity, the study exemplifies how the selected protagonists are portrayed as punished because of their disobedience to the pre-established norm of womanhood. This punishment takes three forms: psychologically, by being devalued, criticised and ignored; professionally, by being legally questioned and accused of severe incompetence and physically by being victims of sexual assault. The conclusion states that, in spite of a century having past since the establish-ment of the norms of womanhood referred to here, the female protagonists act accordingly which indicates that these norms are still current. Furthermore, the portrayal of Scarpetta and Cabbot is dependent on the genre in which they belong which limits the possible expression of gender. It is suggested that the gender categories: men and women are too narrow and that the definition of woman needs to be extended.Within the characterisation of the two prota-gonists in the study there is evidence that they are considered atypical women or homosexuals because of their opposing the traditional views of womanhood.

This thesis deals with enumerative combinatorics applied to three different objects related to partition shapes, namely tableaux, restricted words, and Bruhat intervals. The main scientific contributions are the following. Paper I: Let the sign of a standard Young tableau be the sign of the permutation you get by reading it row by row from left to right, like a book. A conjecture by Richard Stanley says that the sum of the signs of all SYTs with n squares is 2^[n/2]. We prove a generalisation of this conjecture using the Robinson-Schensted correspondence and a new concept called chess tableaux. The proof is built on a remarkably simple relation between the sign of a permutation pi and the signs of its RS-corresponding tableaux P and Q, namely sgn(pi) = (−1)^v sgn(P)sgn(Q), where v is the number of disjoint vertical dominoes that fit in the partition shape of P and Q. The sign-imbalance of a partition shape is defined as the sum of the signs of all standard Young tableaux of that shape. As a further application of the sign-transferring formula above, we also prove a sharpening of another conjecture by Stanley concerning weighted sums of squares of sign-imbalances. Paper II: We generalise some of the results in paper I to skew tableaux. More precisely, we examine how the sign property is transferred by the skew Robinson-Schensted correspondence invented by Sagan and Stanley. The result is a surprisingly simple generalisation of the ordinary non-skew formula above. As an application, we find vanishing weighted sums of squares of sign-imbalances, thereby generalising a variant of Stanley’s second conjecture. Paper III: The following special case of a conjecture by Loehr and Warrington was proved by Ekhad, Vatter, and Zeilberger: There are 10^n zero-sum words of length 5n in the alphabet {+3,−2} such that no consecutive subword begins with +3, ends with −2, and sums to −2. We give a simple bijective proof of the conjecture in its original and more general setting where 3 and 2 are replaced by any relatively prime positive integers a and b, 10^n is replaced by ((a+b) choose a)^n, and 5n is replaced by (a+b)n. To do this we reformulate the problem in terms of cylindrical lattice walks which can be interpreted as the south-east border of certain partition shapes. Paper IV: We characterise the permutations pi such that the elements in the closed lower Bruhat interval [id,pi] of the symmetric group correspond to non-capturing rook configurations on a skew Ferrers board. These intervals turn out to be exactly those whose flag manifolds are defined by inclusions, as defined by Gasharov and Reiner. The characterisation connects Poincaré polynomials (rank-generating functions) of Bruhat intervals with q-rook polynomials, and we are able to compute the Poincaré polynomial of some particularly interesting intervals in the finite Weyl groups A_n and B_n. The expressions involve q-Stirling numbers of the second kind, and for the group A_n putting q = 1 yields the poly-Bernoulli numbers defined by Kaneko. / Ämnet för denna avhandling är enumerativ kombinatorik tillämpad på tre olika objekt med anknytning till partitionsformer, nämligen tablåer, begränsade ord och bruhatintervall. Dom viktigaste vetenskapliga bidragen är följande. Artikel I: Låt tecknet av en standardtablå vara tecknet hos permutationen man får om man läser tablån rad för rad från vänster till höger, som en bok. En förmodan av Richard Stanley säjer att teckensumman av alla standardtablåer med n rutor är 2^[n/2]. Vi visar en generalisering av denna förmodan med hjälp av Robinson-Schensted-korrespondensen och ett nytt begrepp som vi kallar schacktablåer. Beviset bygger på ett anmärkningsvärt enkelt samband mellan tecknet hos en permutation pi och tecknen hos dess RS-motsvarande tablåer P och Q, nämligen sgn(pi)=(-1)^v sgn(P)sgn(Q), där v är antalet disjunkta vertikala dominobrickor som får plats i partitionsformen hos P och Q. Teckenobalansen hos en partitionsform definieras som teckensumman av alla standardtablåer av den formen. Som en ytterligare tillämpning av formeln för teckenöverföring ovan bevisar vi också en starkare variant av en annan förmodan av Stanley som handlar om viktade summor av kvadrerade teckenobalanser. Artikel II: Vi generaliserar några av resultaten i artikel I till skeva tablåer. Närmare bestämt undersöker vi hur teckenegenskapen överförs av Sagan och Stanleys skeva Robinson-Schensted-korrespondens. Resultatet är en förvånansvärt enkel generalisering av den vanliga ickeskeva formeln ovan. Som en tillämpning visar vi att vissa viktade summor av kvadrerade teckenobalanser blir noll, vilket leder till en generalisering av en variant av Stanleys andra förmodan. Artikel III: Följande specialfall av en förmodan av Loehr och Warrington bevisades av Ekhad, Vatter och Zeilberger: Det finns 10^n ord med summan noll av längd 5n i alfabetet {+3,-2} sådana att inget sammanhängande delord börjar med +3, slutar med -2 och har summan -2. Vi ger ett enkelt bevis för denna förmodan i dess ursprungliga allmännare utförande där 3 och 2 byts ut mot vilka som helst relativt prima positiva heltal a och b, 10^n byts ut mot ((a+b) över a)^n och 5n mot (a+b)n. För att göra detta formulerar vi problemet i termer av cylindriska latticestigar som kan tolkas som den sydöstra gränslinjen för vissa partitionsformer. Artikel IV: Vi karakteriserar dom permutationer pi sådana att elementen i det slutna bruhatintervallet [id,pi] i symmetriska gruppen motsvarar ickeslående tornplaceringar på ett skevt ferrersbräde. Dessa intervall visar sej vara precis dom vars flaggmångfalder är definierade av inklusioner, ett begrepp introducerat av Gasharov och Reiner. Karakteriseringen skapar en länk mellan poincarépolynom (ranggenererande funktioner) för bruhatintervall och q-tornpolynom, och vi kan beräkna poincarépolynomet för några särskilt intressanta intervall i dom ändliga weylgrupperna A_n och B_n. Uttrycken innehåller q-stirlingtal av andra sorten, och sätter man q=1 för grupp A_n så får man Kanekos poly-bernoullital. / QC 20100818

The role of communities associated to a substrate as fundamental components of an aquatic system has been recognized by many authors. Although periphyton has been considered of great importance in shallow lakes, its inclusion in different ecological models has been unusual. Phillips et al. (1978) were the first in considering epiphyton as an internal mechanism leading the system to a change in its state from greater water transparecy to more turbid conditions. In contrast, Scheffer et al. (1993) proposed the Alternative Equilibria Hypothesis (AEH), which considers that a shallow lake can alternate between two states, a Clear Water State (stabilized by the presence of submerged macrophytes) and a Turbid Water State (stabilized by an elevated phytoplankton biomass), excluding in this scheme the periphytic communities. Later only the conceptual model coined by Goldsborough and Robinson (1996, G&R model) emphasizes again the importance of epiphyton as well as that of epipelon and metaphyton by establishing the possibility of occurrence of four states according to the contributions to the total algal biomass of each of the algal taxocenosis. Some analyses of the system’s dynamics have been performed in pampean lakes in the context of the AEH. On the other hand, knowledge regarding periphytic and benthic communities is still poor. We propose as an hypothesis that phytoperiphyton will respond to the occurrence of different equilibria states, displaying, at the same time, strong interrelationships with the phytobenthos as well as with the phytoplankton. On the other hand, we consider the possibility that the phytoperiphytic and phytobenthic assemblages may function as internal mechanisms both, as state change or as state stability factors. Finally, we assess the importance of phytoperiphyton as regards its contributions to the total algal biomass in the context of the G&R model, comparing then the results with those obtained in the case of the AEH. The general objectives of the present investigation are to gather information about the structure and dynamics of the phytoperiphyton and its relationships with environmental factors as well as with the phytobenthon and phytoplankton in a pampean shallow lake; and to analyze phytoperiphytic dynamics under the AEH and the G&R model contexts, evaluating periphytic contributions to the total algal biomass. This investigation was carried out in an seepage shallow lake, Lacombe Lake, which is included in the “Grupo Marginal de lagunas” group in the pericoastal region of Provincia de Buenos Aires. Sampling was performed from July 2001 to June 2002 at four sites according to their exposure to environmental factors and the presence of macrophytes: bulrush beds, (JP and JC); and sites devoided of emergent vegetation but with stands of submerged macrophytes during the growing season (ALe and ALr). J sites and ALe were also representative of deeper zones and ALr of a site near the shore. Environmental variables were measured in situ and water samples were collected for chemical analysis and for plankton identification and quantification, following a vertical profile (excepting in ALr). In the case of phytoperiphyton, bulrush epiphyte samples (epiphyton) were taken following a vertical profile and those of submerged macrophytes were collected from the first 25 cm of the stems. Benthon (epipelon) was sampled using a corer. Aliquots for chemical analysis were also extracted from those samples. Vegetal substrate dynamics was also evaluated during sampling. At the laboratory, concentrations of algal nutrients, of the eight principal ions and of soluble polyphenols, as well as alkalinity and total hardness were measured. Phytoplanktonic, epiphytic and epipelic samples were treated for active a chlorophyll and pheopigment determinations. Organism identification and quantification were made according to standardized and own developed methods. First, variations in biotic and abiotic variables were analyzed for the determination of different equilibrium states occurrence. Three perturbation events were registered: precipitations in August, October and March. All of them involved water level increases and conductivity diminutions. Especially in the first two events, nutrient input from runoff was observed; meanwhile in March the input of water determined the dilution in nutrients concentrations. On the other hand, light conditions improved, particularly from October onwards, when stands of submerged macrophytes developed and a decrease of phytoplankton density and a change in its specific composition was detected. The latter being generated by the dilution effects of water input, the shading of the aquatic plants and algal consumption by cladocerans. March event also involved an improvement of light underwater climate but the increase in the water level affected macrophyte stands which mainly withdrawed to the shallowest zones. As regards phytoplankton, changes in the specific composition were recorded again. The statistic evaluation of these facts in conjunction with the analysis of permanence, resiliency and resistance properties of the dominating taxocenosis leads to interpret in the context of the AEH that two equilibria states occurred in the shallow lake. During the first three months a Turbid Water State developed, given by the phytoplankton domination given by an oscilatorial cyanophyte, minor transparency and relatively higher nutrient concentrations. In October and November the passage between states occurred, thus considering these months as transitional. From December onwards a Clear Water State established given by extended development of stands of submerged macrophytes, greater water transparency and minor nutrient concentrations. Finally, from March to May, given the submerged macrophyte withdrawal to shallowest sectors it can be interpreted that the system oscillated around a clear water state, or else, taking into account changes in the planktonic community, it is suggested that a third different state established, the “mixed phytoplankton” state. It is also suggested that states developed in Lacombe could be alternative. Next, the structure and dynamics of phytoperiphyton on bulrush and submerged macrophytes was analyzed. Vertical spatial and temporal variations of bulrush epiphyton showed to be more important than differences between sites. These variations involved smaller biomass values and a simpler physiognomy during turbid water phase and along the vertical gradient in all sampling occasions. In October, related to better light underwater conditions and the nutrient input, epiphytic biomass increased, principally promoted by species typical of the turbid phase. Nonetheless, a structural change started in this month, driven by herbivores but also by the modification of internal relationships between members of the same taxocenosis (shading and less bare substrate to be colonized). This resulted in the establishment of the characteristic assemblages of the clear water phase. During the first three months domination by stalked diatoms structured the community in a unique stratum, resistant to the less favourable light conditions and resilient to August perturbations. From December onwards Spirogyra species dominated, constituting the upper stratum, followed by Oedogonium species in the middle stratum and diatoms in the lower one. These assemblages were stabilized by mechanisms mainly displayed by the zignematalean taxon (shading, epifitism inhibition), allowing to considerer that they were resilient to March perturbation event (de novo establishment on non previously colonized surfaces). In face of the permanence, resistance and resilience properties showed by the taxocenosis, two different states of bulrush phytoperiphyton are considered: turbid water and clear water assemblages. This temporal pattern appeared less well delimited with depth and showed up later in time. Epiphyton data suggested that both states could be alternative. Differences between sites could be observed in respect to phytoperiphyton growing on submerged macrophytes, but the same temporal pattern showed by bulrush periphyton couldn’t be detected due to a great variability in the data gathered. In the next section, the analysis of the structure and dynamics of the phytobenton was carried out. It was showed that differences between the deepest sampling points and the shallowest site were greater than temporal ones. The composition of the assemblages was scarcely variable in time. The taxocenosis was principally related to the poor light conditions recorded on the sediment surface throughout the entire sampling period, even during the clear water phase. The examination of the specific composition in function of its origin evidenced the influence that the epipelon receives from other taxocenosis, constituting a refuge site for allochthonous taxa during unfavourable situations. The scarce variability of the epipelic fraction is also showed. In this way, it is considered that the taxocenosis maintained itself in only one state, indifferent to state changes in the lake and principally resisting the darkness and bearing to live in the unstable sediments. Subsequently, first the roles of the phytoperiphyton and complementary those of phytobenton, as state change or state stability agents were evaluated. The harmful effect of the phytoperiphyton on submerged macrophytes was probably counteracted by plant ramification production and allelopathy. The evidence suggested that its role as nutrient sequestrator is of minor importance in this case, due to other factors that might have disturbed phytoplankton more intensely than competition with phytoperiphyton. Much evidence supported the role of phytobenton as a source of epiphytic and planktonic species belonging either to turbid and clear water state assemblages. The results did not support the hypothesis that phytobenton may play a role as a sediment-stabilizing factor. On the contrary, it may be perturbating agent. Next, an analysis of the contributions of each community to the total algal biomass in the context of the G&R model was performed. Comparisons with AEH results were also carried out. This leaded to the consideration of the occurrence of the following states in Lacombe Lake: a Lake State consistent with the Turbid Water phase, an Open State consistent with the Clear Water phase and local Dry States in ALr site occurred both during the turbid water phase (July) or the clear water situation (March-April). The substantial contribution of epiphyton especially, that growing on submerged macrophytes, is emphasized. The importance of the discrimination of different fractions of epipelon material according to its origin when evaluating the contributions of each community to total algal biomass is also highlighted. Finally, a new interpretation is presented based on algal taxocenosis dynamics, which incorporates elements from both, the AEH and the G&R model. In conclusion, phytoperiphyton in this pampean shallow lake is strongly affected by the factors that determine the establishment or passage from one equilibrium state to another. These assemblages respond to changes through modifications in their own internal structure. These structures gradually alter with depth, remaining these changes more fully explained by the comparison with phytobenton dynamics. Besides the possible roles that the taxocenosis might undertake as an internal mechanism in the change or stabilization of systems states in different situations other than those encountered during this study, epiphyton importance in the systems context, is principally evidenced by the great contribution that these taxocenosis make to the total algal biomass, constituting the dominant compartment during clear water states. / El rol de las comunidades relacionadas a un sustrato como componentes fundamentales dentro de un sistema acuático ha sido reconocido por varios autores. A pesar de la importancia dada al perifiton en lagos someros, su inclusión dentro de diferentes modelos ecológicos ha sido inusual. Phillips et al. (1978) son los primeros en considerar al epifiton como un mecanismo interno en el pasaje de un estado de aguas transparentes a otro más turbio. En contraste, Scheffer et al. (1993), proponen la Hipótesis de Estados de Equilibrio Alternativos (HEEA) que considera que un lago somero puede alternar entre dos estados, uno de Aguas Claras, (estabilizado por la presencia de macrófitas sumegidas) y otro de Aguas Turbias (estabilizado por la elevada biomasa de fitoplancton), no tomando en consideración a las comunidades perifiticas. Sólo el marco conceptual propuesto por Goldsborough y Robinson (1996, modelo G&R) da nuevamente relevancia al epifiton, incluyendo al epipelon, al metafiton y al fitoplancton dentro de un modelo ecológico, discriminando cuatro estados de acuerdo a la dominancia en la biomasa algal total de alguna de estas taxocenosis. En las lagunas pampeanas se han realizado algunos análisis de la dinámica de los sistemas en el marco de la HEEA. Por otro lado, el conocimiento acerca de las comunidades perifíticas y bentónicas todavía es escaso. Se propone como hipótesis que el fitoperifiton variará de acuerdo a la ocurrencia de los diferentes estados en la laguna (según HEEA), interrelacionándose al mismo tiempo con el fitobenton y el fitoplancton. Por otro lado, también se considera la posibilidad de que tanto los ensambles fitoperifíticos como fitobentónicos sean mecanismos internos en el pasaje o en la estabilización de un estado. Por último, se valora la importancia del fitoperifiton en cuanto a sus aportes a la biomasa algal total en el marco del modelo G&R, realizando comparaciones con los resultados obtenidos en el caso de la HEEA. Los objetivos generales de esta investigación son: obtener información acerca de la dinámica y estructura del fitoperifiton y su relación con factores ambientales así como, también, acerca de sus interrelaciones con el fitobenton y el fitoplancton en una laguna pampeana; y analizar su dinámica en el marco de la HEEA y del modelo G&R valorando los aportes del fitoperifiton a la biomasa algal total. El estudio se realizó en la laguna Lacombe comprendida en el Grupo Marginal de lagunas en la región pericostera de la Provincia de Buenos Aires. Los muestreos se realizaron desde julio 2001 a junio 2002 en cuatro sitios de acuerdo a su grado de exposición a las variables ambientales y la presencia de macrófitas: Juncales (JP y JC); sitios de Aguas Libres con o sin macrófitas sumergidas durante la época de crecimiento (ALe y ALr). Los sitios J y ALe representan, puntos de mayor profundidad y ALr un sitio cercano a la orilla. Siguiendo un perfil vertical (con excepción del sitio cercano a la orilla, ALr) se midieron variables ambientales in situ y se tomaron muestras de agua para realizar análisis químicos del agua y la identificación y la cuantificación del plancton. En el caso del fitoperifiton se tomaron muestras de epifitos sobre junco (epifiton) también en un perfil vertical y en los 25 cm apicales del tallo de plantas sumergidas. El benton (epipelon) fue muestreado con un corer, extrayendo muestras también para realizar análisis químicos de los sedimentos. En el campo también se evaluaron las dinámicas de los sustratos vegetales. En el laboratorio se midieron las concentraciones de nutrientes algales, de los ocho iones principales, de los polifenoles solubles así como también la reserva alcalina y la dureza total. Las muestras de fitoplancton, epifiton y epipelon fueron tratadas para la estimación de clorofila a activa y feopigmentos, y la identificación y cuantificación de organismos según métodos estandarizados y propios. En principio, se analizaron las variables bióticas y abióticas para determinar la ocurrencia de estados de equilibrio en la laguna. Tres eventos principales de perturbación ocurrieron durante el período de estudio: las precipitaciones en agosto, octubre y marzo. Todas ellas involucraron aumentos del nivel hidrométrico y disminuciones en la conductividad. En los dos primeros, especialmente en octubre, se produjo la entrada de nutrientes por escorrentía, en tanto que en marzo el aporte de agua resultó en la dilución de los mismos. Por otro lado, las condiciones lumínicas mejoraron especialmente a partir de octubre, lo que se relacionó con el desarrollo de manchones de macrófitas sumergidas y una menor densidad y composición diferente del fitoplancton. Esto último se produjo por los efectos de dilución de la entrada de agua, el sombreado de las plantas acuáticas y por el pastoreo de cladóceros. El evento de marzo involucró también un mejoramiento de las condiciones de luz en la columna de agua pero, paralelamente, determinó la retracción de los manchones de macrófitas sumergidas hasta zonas más cercanas a la orilla. En el fitoplancton se operaron cambios en la composición específica. La evaluación estadística de estos hechos junto con el análisis de las características de permanencia, resiliencia y resistencia de las taxocenosis dominantes condujeron a interpretar que durante el período de estudio se establecen dos estados de equilibrio según la HEEA. Durante los tres primeros meses se desarrolló un estado de aguas turbias definido por la dominancia del fitoplancton con el predominio de una oscilatorial, menor transparencia y concentraciones de nutrientes relativamente más elevadas. En octubre y noviembre se produjo el pasaje entre estados, considerándose a estos meses como transicionales. De diciembre hasta el final del estudio, se desarrolló un estado de aguas claras definido por la presencia de manchones de macrófitas, mayor transparencia del agua y menores concentraciones de nutrientes. Finalmente, de marzo hasta mayo, dada la retracción de los manchones de macrófitas sumergidas, se puede interpretar que ocurrió una oscilación del sistema alrededor de un estado de aguas claras o, dados los cambios operados en el plancton, un tercer estado “mixed phytoplankton”. Se evidenció que los estados establecidos podrían ser alternativos. Seguidamente se analizaron la estructura y dinámica del fitoperifiton sobre junco y las macrófitas sumergidas. Las variaciones espaciales verticales y temporales en la dinámica del perifiton sobre junco resultaron más marcadas que las espaciales horizontales (entre sitios). Estas variaciones implicaron una menor biomasa y una fisonomía más simple durante la fase de aguas turbias y a lo largo del perfil vertical en todas las fechas. Relacionado con el incremento de la luz en la columna de agua y por la entrada de nutrientes en octubre, la biomasa epifítica aumentó, impulsada por las especies características de la fase turbia. Sin embargo, a partir de ese mes se dió un cambio estructural, generado por el pastoreo pero, también, por la modificación en las relaciones entre los componentes de la taxocenosis (autosombreado y menor disponibilidad de sustrato libre) que desembocó en el establecimiento de los ensambles característicos de la fase clara. Durante los tres primeros meses el predominio de diatomeas pedunculadas conformó una comunidad uniestrato, resistente a una menor disponibilidad de la luz y resiliente frente a las perturbaciones de agosto. De diciembre a febrero se desarrolló un ensamble donde predominan las especies de Spirogyra formando un estrato superior, las de Oedogonium en un estrato medio y las diatomeas en un estrato inferior. Estos ensambles presentaron mecanismos de estabilización dados por los talos de la zignematal (sombreado, inhibición del crecimiento de epifitos secundarios), considerándose resilientes frente a las perturbaciones de marzo (desarrollo de los ensambles en sitios previamente no colonizados). En función de las características de permanencia, resistencia y resiliencia, se diferenciaron dos estados en el fitoperifiton de junco: ensambles de fase turbia y ensambles de fase clara. Este patrón temporal se hizo menos marcado en profundidad y aparece en forma retrasada en el tiempo. Los datos habrían indicado la posibilidad de que ambos estados fuesen alternativos. El fitoperifiton sobre macrófitas sumergidas presentó variaciones definidas en el sentido espacial horizontal (mayor biomasa en sitios más profundos) pero no se detectó un patrón temporal, similar al del perifiton sobre junco, dada la gran variabilidad de los datos obtenidos. En el apartado siguiente se analizaron la estructura y dinámica del fitobenton. Se estableció que las variaciones entre sitios de muestreo fueron más marcadas que las temporales. Los ensambles epipélicos presentaron en general una composición escasamente variable a lo largo del tiempo relacionándose principalmente con la disponibilidad de luz. Ésta fue escasa durante todo el período de estudio por lo que las condiciones de crecimiento para las algas béntonicas no fueron favorables, aún con los cambios de estado en la laguna. El análisis del material en función de su origen evidenció las influencias que esta comunidad recibe desde otros ensambles, siendo un sitio de refugio para organismos alóctonos durante épocas desfavorables. También se evidenció la escasa variabilidad de la fracción epipélica propiamente dicha durante todo el período de estudio. Así, se considera que esta taxocenosis se mantuvo en un solo estado, ajena al pasaje de estado en la laguna, principalmente resistiendo la falta de luz y la inestabilidad de los sedimentos. Posteriormente, se evaluó primeramente el papel del fitoperifiton y, en forma complementaria, el del fitobenton como impulsores del pasaje de estados o como estabilizadores de los mismos en la laguna. El efecto de sombreado del fitoperifiton sobre macrófitas sumergidas probablemente fue contrarrestado por la producción de nuevas ramificaciones de las macrófitas y por alelopatía. Las evidencias señalaron que su rol como secuestradores de nutrientes disponibles para el fitoplancton fue menor en este caso, dado que éste último se halla perturbado por otros factores más que por la competencia con el epifiton. Las evidencias señalaron al epipelon como simiente de especies del epifiton y del fitoplancton tanto pertenecientes a la fase turbia como a la clara. En cambio, los resultados no avalaron su rol como estabilizador de los sedimentos. Al contrario, podría ser una perturbación de éstos. A continuación, se examinaron las contribuciones de las taxocenosis a la biomasa algal total en el marco del modelo G&R. También se realizó la comparación de los resultados con aquellos obtenidos a partir de la HEEA. Se consideró la ocurrencia de un estado Lake State congruente con la fase turbia en la laguna, un estado Open State congruente con la fase clara y estados locales Dry State en ALr tanto en la fase turbia (julio) como en la clara (marzo-abril). Se destacó la substancial contribución del epifiton sobre macrófitas sumergidas. También, se subrayó la importancia de discriminar, en relación con el epipelon, los aportes de cada una de las taxocenosis cuando se evalúan las contribuciones a la biomasa algal total. Finalmente, se ofreció una interpretación basada sobre la dinámica de las taxocenosis algales considerando elementos de la HEEA y del modelo G&R. En conclusión, el fitoperifiton en las lagunas pampeanas fue fuertemente influido por los factores que determinan los estados de equilibrio, respondiendo al cambio de los mismos con la modificación en su estructura interna. Ésta se alteró gradualmente con la profundidad, quedando estos cambios más completamente explicados a través de la comparación con la dinámica del fitobenton. Además de los posibles roles que podría desempeñar como mecanismo interno de pasaje o como estabilizador de estados en situaciones diferentes a las halladas en Lacombe, su importancia en el contexto del sistema se manifiesta en el gran aporte que realiza a la biomasa algal total, constituyendo el compartimiento dominante en los estados de aguas claras.

Hayy Bin Yaqzan is a famous Arabic narrative written by the Muslim philosopher Abu Bakr Ibn Tufail in the twelfth century and translated first into Latin by Edward Pocock, the son, in 1671, then into English by George Keith in 1674, by George Ashwell in 1686, and by Simon Ockley in 1708. Ibn Tufail's work is mentioned in connection with Daniel Defoe's Robinson Crusoe, which appeared in 1719, by many critics who either accentuate or repudiate its significance as a possible source. This study goes beyond the off-hand question of derivation to compare these two analogous books, not to take part in the long-standing dispute but to inquire into the premises it stands upon and investigate its motivating grounds. After pointing out the identical settings of two men each stranded on a desert island, this study proceeds to analyze the approach of each book to the relationship between man and Nature. In the process of mastering their environments, Hayy and Crusoe awaken to the providential presence behind natural forces and learn to regulate themselves within the divine scheme and to form strong relations with God. The narratives of Ibn Tufail and Defoe share a concern not only with their heroes' solitude but also with their attitudes toward society, which threatens their sense of individuality. Whereas Hayy prefers his solitary state to immersion in human society and remains on his island accompanied only by one faithful apostle, Crusoe eagerly sails back to the world of men, although he too adjusts poorly to the spirit of society and spends the rest of his life roaming the globe. Examining the technical aspects of Robinson Crusoe and Hayy Bin Yaqzan, their narrative methods, their chronological order, their structure, style, and delineation of character, the study concludes that although the two books belong to different genres, they are still more similar than ordinarily assumed. It also finds that the question of indebtedness, which may never be resolved, is less significant than the broader similarities in cultural, political, and religious circumstances which may be at work.

Embedded within various works of Eighteenth-Century literature lie themes regarding how the protagonists of these stories pursue their own versions of happiness. This thesis examines how characters from a wide variety of Eighteenth-Century novels engage with their surroundings, often resisting the dominant social structures of the time, to fashion more fulfilling lives for themselves. From Robinson Crusoe to Elizabeth Bennet to Frankenstein's monster, these characters come from a wide variety of backgrounds but all reveal several unifying themes. They seek out personal connections rather that striving to fulfill antiquated social expectations and they focus on their own agency, rather than circumstances out of their control. Their respective journeys are often fraught with peril, but each one is a journey worth embarking on.