Memory studies - kohti tutkimusalueen vakiintumista

Teemanumero 2/2011: Media ja menneisyys.

Lectio praecursoria : Systems between information and knowledge : in a memory management model of an extended enterprise

VTT Jouni Meriluodon valtio-opin alaan kuuluva väitöskirja Systems between information and knowledge : in a memory management model of an extended enterprise tarkastettiin 21.6.2011 Helsingin yliopistossa.

Memory Effects in the Dynamics of Open Quantum Systems

In this Thesis various aspects of memory effects in the dynamics of open quantum systems are studied. We develop a general theoretical framework for open quantum systems beyond the Markov approximation which allows us to investigate different sources of memory effects and to develop methods for harnessing them in order to realise controllable open quantum systems. In the first part of the Thesis a characterisation of non-Markovian dynamics in terms of information flow is developed and applied to study different sources of memory effects. Namely, we study nonlocal memory effects which arise due to initial correlations between two local environments and further the memory effects induced by initial correlations between the open system and the environment. The last part focuses on describing two all-optical experiment in which through selective preparation of the initial environment states the information flow between the system and the environment can be controlled. In the first experiment the system is driven from the Markovian to the non- Markovian regime and the degree of non-Markovianity is determined. In the second experiment we observe the nonlocal nature of the memory effects and provide a novel method to experimentally quantify frequency correlations in photonic environments via polarisation measurements.

Mythology as a key to historical ways of thinking

Kirjallisuusarvostelu

Neurocognitive changes in early-stage Parkinson's disease : functional and structural brain correlates of memory and verbal functions

Resultaten påvisade små, men mätbara försämringar i minnes- och verbal förmåga hos personer som haft Parkinsons sjukdom under tre år. Jämfört med en kontrollgrupp uppvisade Parkinsonpatienter avvikande responser i hjärnans elektriska aktivitet under en korttidsminnesuppgift, och de presterade även sämre i olika typer av andra minnesuppgifter. Försämring i en specifik typ av minnesuppgift korrelerade med förminskad volym i höger hjärnhalva. Samband hittades också mellan sämre verbal förmåga och förminskad volym i djupa hjärnstrukturer. Förminskad hjärnvolym har tidigare påvisats hos dementa patienter i senare sjukdomsstadier. Forskningsresultaten bidrar med ny kunskap om kognitiva symptom och deras neurala bakgrund vid Parkinsons sjukdom. De tyder också på att tidig kognitiv funktionsnedsättning kan identifieras, vilket kan bidra till utvecklingen av sjukdomens behandling. Parkinsons sjukdom är den näst vanligaste neurogeriatriska sjukdomen efter Alzheimers sjukdom. Symptomen uppstår som följd av förminskad produktion av hjärnans transmittorämne dopamin. Parkinsons sjukdom har traditionellt betraktats som en progressiv motorisk sjukdom. Ny forskning tyder på att multipla hjärnsystem skadas, vilket resulterar i att även tankeprocesser påverkas. 75-80% uppskattas insjukna i demens 10-15 år efter diagnos, men det kognitiva sjukdomsförloppet och orsaken till demenssymptomen är tillsvidare okänd. I Finland uppskattas ca 10-12 000 personer ha Parkinsons sjukdom, varav ca 3 000 uppskattas ha demens. ----------------------------------------------------------------------------------------------------------------------------------------------------- Tutkimuksessa todettiin lieviä muutoksia muisti- ja kielellisissä toiminnoissa alle kolme vuotta sairastaneilla Parkinson-potilailla. Potilailla havaittiin poikkeavia aivosähkötoiminnan vasteita lyhytkestoista muistia mittaavan tehtävän aikana. Potilaat suoriutuivat myös verrokkiryhmää heikommin useissa muistitehtävissä. Heikentynyt tahaton muisti liittyi pienempään aivokuoren harmaan aineen paikalliseen tilavuuteen. Heikompi kielellinen suoriutuminen liittyi pienempään harmaan aineen tilavuuteen aivojen syvissä rakenteissa. Pienentyneitä aivorakenteiden tilavuuksia on aiemmin todettu dementoituneilla Parkinson-potilailla sairauden myöhemmissä vaiheissa. Tutkimustulokset tuovat uutta tietoa Parkinsonin taudin kognitiivisista oireista ja niiden aivoperäisestä taustasta. Tulosten perusteella on mahdollista tunnistaa jo varhaisia kognitiivisia muutoksia, mikä voi mahdollistaa tehokkaamman hoidon kohdentamisen. Parkinsonin tauti on Alzheimerin taudin jälkeen toiseksi yleisin neurogeriatrinen sairaus. Oirekuva liittyy aivojen dopaminergisen järjestelmän rappeutumiseen. Perinteisesti liikehäiriösairaudeksi luokiteltu sairaus vaurioittaa lukuisia muita aivojärjestelmiä aiheuttaen muutoksia myös mm. ajattelutoiminnoissa. Pitkään sairastaneista 75–80 prosentilla esiintyy dementiaoireita, mutta oireiden syy ja kehityskaari tunnetaan toistaiseksi huonosti. Suomessa on arviolta 10–12 000 Parkinson-potilasta, joista noin 3 000 arvioidaan kärsivän dementiaoireista.

Predicting bankruptcy of Finnish limited liability companies from historical financial statements

This master’s thesis studies the probability of bankruptcy of Finnish limited liability companies as a part of credit risk assessment. The main idea of this thesis is to build and test bankruptcy prediction models for Finnish limited liability companies that can be utilized in credit decision making. The data used in this thesis consists of historical financial statements from 2112 Finnish limited liability companies, half of which have filed for bankruptcy. A total of four models are developed, two with logistic regression and two with multivariate discriminant analysis (MDA). The time horizon of the models varies from 1 to 2 years prior to the bankruptcy, and 14 different financial variables are used in the model formation. The results show that the prediction accuracy of the models ranges between 81.7% and 88.9%, and the best prediction accuracy is achieved with the one year prior the bankruptcy logistic regression model. However the difference between the best logistic model and the best MDA model is minimal. Overall based on the results of this thesis it can be concluded that predicting bankruptcy is possible to some extent, but naturally the results are not perfect.

Collective Memory Embodied in Poetry as Poison. The Mnemonic Role of Romantic Poets Discussed on the Basis of Adam Mickiewicz’ Konrad Wallenrod and Forefathers (Part III)

This thesis constitutes an interdisciplinary approach to the Polish Romanticism combining literature studies with memory studies, nationalism research and psychoanalysis. This phenomenon-based study attempts to answer the question, how the Polish national poet Adam Mickiewicz (1798–1855) – or more exactly the implied authors in his works – perceived the role of poetry in mnemonic terms and how it changes in course of time. Consequently, ‘memory in literature’ (Astrin Erll and Ansger Nünning) is discussed here. Two pieces of writing by Mickiewicz – Konrad Wallenrod [1828] and the third part of Forefathers [1832], where a bard respectively a poetic genius appears – are seen as meta-texts defining goals of poets in time of the political non-existence of a state. Poetry is supposed to keep memory of the glorious past alive, kindle the love for the motherland, support the collective identity of a group and initiate a liberation movement. Poets function as memory guards, leaders of the nation and prophets. Thus, literature is a medium of collective memory – it stores crucial contents, transmits them and acts as a cue. Nevertheless, shifting the focus from the community towards well-being of individuals, which is consistent with the postmodern thinking, the impact that poetry has on members of a given memory culture (Jan Assmann) can be described in ‘vampiric’ terms (Maria Janion). Poetry embodying collective memory may be compared to ‘poison’, ‘infecting’ people with a nationalistic way of thinking to their disadvantage as far as their personal lives are concerned.

Conflicting Memory in Estonia: How Do Estonian Russian-speakers Understand the Events of 1939-40?

This thesis studies the collective memory of the Russian-speaking minority living in Estonia. The minority is exposed to two national narratives regarding the incorporation of Estonia into the Soviet Union in 1940. According to the Estonian narrative, Estonia was occupied and annexed by the Soviet Union while the Soviet-Russian narrative sees the actions to have been legal and voluntary. This thesis firstly examines thoughts the existence of these two opposing narratives evoke among the Russian-speaking minority and secondly it explores whether the views of the minority compare with the two official yet divergent narratives. The study focuses on the second and third generation minority members. The topic belongs to the field of memory studies. The objective is to understand the views the Russian minority have towards the controversial events of the years 1939-40. To accomplish the objectives set, a web-based survey using open-ended and multiple-choice questions was conducted. The open-ended questions addressed the main research questions while the multiple-choice questions contributed to forming a more comprehensive understanding of the subject in question. In order to interpret the data, qualitative content analysis has been applied. Based on the findings, the Russian-speaking minority respondents’ understanding of the events of 1939-40 could be described as fragmented, inconsistent and including viewpoints that resulted from the merger of different storylines. There is no single cohesive or coherent narrative of the past amongst the minority. In addition to that, their views do not generally comply with the narrative of the Russian Federation as often referred to in literature, even though the minority respondents do not want to see the Soviet involvement as critically as the Estonian narrative does. Many respondents conceive the events of 1939-40 as ambiguous revealing the ability to be tolerant and receptive in their views regarding the past.