Johdon laskentatoimen ohjaus- ja hallintajärjestelmien hyödyntäminen yritysverkostoissa

Tutkimuksen aiheena on johdon laskentatoimen ohjaus- ja hallintajärjestelmien hyödyntäminen yritysverkostoissa. Yritysten välisten suhteiden hallinnassa käytettävät menetelmät koostuvat pääasiassa johdon laskentatoimen ja suorituskyvyn mittaamisen menetelmistä. Verkostojen ohjaus ja hallinta on tärkeää, koska se on verkostojen tehokkaan toiminnan kriittinen menestystekijä ja kilpailuedun lähde. Suorituskyvyn mittaamisella, johdon laskentatoimella ja johdon kontrollitehtävällä on keskenään riippuvuussuhteet, joiden pitäisi toimia sopusoinnussa. Suorituskyvyn mittaamisen ja johdon laskentatoimen tutkimus yritysten verkostoympäristöissä on kohtalaisen tuore ilmiö, jonka vuoksi aihealueen tutkimus on vielä varsin pirstaleista ja hajanaista. Tämän vuoksi tutkimuksen tavoite on muodostaa selkeä kokonaiskuva siitä kuinka johdon laskentatoimen ohjaus- ja hallintajärjestelmiä voidaan hyödyntää yritysverkostojen ohjauksessa ja hallinnassa. Tutkimuksessa myös selvitetään mitä haasteita näiden menetelmien hyödyntämiseen yritysverkostoissa sisältyy. Tutkimusaineistona on käytetty aikaisempia tutkimuksia sekä tutkimusta varten tehtyjä haastatteluita. Tutkimukseen haastateltiin neljästä yritysverkostosta henkilöitä, jotka vastasivat verkoston toiminnasta. Haastatteluiden avulla pyritään täydentämään kirjallisuuskatsauksen pohjalta luotua teoriaa ja selvittämään kuinka verkoston ohjaus- ja hallinta hoidetaan haastateltavissa verkostoissa, millä menetelmin ja mitä haasteita siihen liittyy. Verkostotoimintaan soveltuvien menetelmien ja suorituskykymittareiden kehittäminen on hankalaa, koska jokaisen verkoston tarpeet ja haasteet ovat erilaiset. Uusien menetelmien kehittämiselle ei nähdä tarvetta, vaan kyse on olemassa olevien menetelmien soveltamisesta verkostonäkökulmasta. Menetelmät on rakennettu yksittäisen yrityksen mittaamiseen, joten ne eivät sovellu sellaisenaan käytettäväksi verkostoihin, vaan niitä täytyy kehittää verkoston yksilöllisten tarpeiden mukaan. Tämä vaatii kuitenkin verkostolta osaamista ja halua kehittyä. Verkostojen haasteet liittyvät sekä yritystasolle että verkostotasolle. Yritysten tuottaman informaation, laskentajärjestelmien, tietotaidon, resurssien ja kehityshalun tulee olla hyvällä tasolla, jotta koko verkoston mittaaminen onnistuu luotettavasti. Lisäksi verkostotoiminta pitää sisällään laskentateknisiä, menetelmiin ja informaation vaihtamiseen liittyviä haasteita. Verkostoympäristön laskentatoimen tutkimuksessa ei ole yhtenäistä, laajasti hyväksyttyä teoriaa, koska tutkimussuuntaukset ja –tulokset ovat moniulotteisia ja vaihtelevia.

ERBB4 mutations in cancer and amyotrophic lateral sclerosis

ErbB receptor tyrosine kinases, epidermal growth factor receptor (EGFR, also known as ErbB1), ErbB2 (HER2 or NEU), ErbB3 (HER3), and ErbB4 (HER4), transduce signals borne by extracellular ligands into central cellular responses such as proliferation, survival, differentiation, and apoptosis. Mutations in ERBB genes are frequently detected in human malignant diseases of epithelial and neural origin, making ErbB receptors important drug targets. Targeting EGFR and ErbB2 has been successful in eg. lung and breast cancer, respectively, and mutations in these genes can be used to select patients that are responsive to the targeted treatment. Although somatic ERBB4 mutations have been found in many high-incidence cancers such as melanoma, lung cancer, and colorectal cancer and germ-line ERBB4 mutations have been linked to neuronal disorders and cancer, ErbB4 has generally been neglected as a potential drug target. Thus, the consequences of ERBB4 mutations on ErbB4 biology are largely unknown. This thesis aimed to elucidate the functional consequences and assess the clinical significance of somatic and germ-line ERBB4 mutations in the context of cancer and amyotrophic lateral sclerosis. The results of this study indicated that cancer-associated ERBB4 mutations can promote aberrant ErbB4 function by activating the receptor or inducing qualitative changes in ErbB4 signaling. ERBB4 mutations increased survival or decreased differentiation in vitro, suggesting that ERBB4 mutations can be oncogenic. Importantly, the potentially oncogenic mutations were located in various subdomains in ErbB4, possibly providing explanation for the characteristic scattered pattern of mutations in ERBB4. This study also demonstrated that hereditary variation in ERBB4 gene can have a significant effect on the prognosis of breast cancer. In addition, it was shown that hereditary or de novo germ-line ERBB4 mutations that predispose to amyotrophic lateral sclerosis inhibit ErbB4 activity. Together, these results suggest that ErbB4 should be considered as a novel drug target in cancer and amyotrophic lateral sclerosis.

Effects of different general anesthetics on serum hemolysis and hepatic and muscular glycogenolysis in rats

Anesthetics can affect the structure and biological function of tissues and systems differentially. The aim of the present study was to compare three injectable anesthetics generally used in experiments with animals in terms of the degree of hemolysis and glycogenolysis occurring after profound anesthesia. Twenty-four male Wistar rats (330-440 g) were divided into three groups (N = 8): chloral hydrate (CH), ketamine + xylazine (KX), Zoletil 50® (zolazepam and tiletamine) + xylazine (ZTX). After deep anesthesia, total blood was collected. The liver and white (WG) and red gastrocnemius (RG) muscles were also immediately removed. The degree of serum hemolysis was quantified on the basis of hemoglobin concentration (g/L). Hepatic and muscular glycogen concentrations (mmol/kg wet tissue) were quantified by the phenol-sulfuric method. The CH and KX groups exhibited serum hemolysis (4.0 ± 2.2 and 1.9 ± 0.9 g/L, respectively; P < 0.05) compared to the ZTX group, which presented none. Only KX induced elevated glycogenolysis (mmol/kg wet tissue) in the liver (86.9 ± 63.2) and in WG (18.7 ± 9.0) and RG (15.2 ± 7.2; P < 0.05). The CH and ZTX groups exhibited no glycogenolysis in the liver (164.4 ± 41.1 and 176.8 ± 54.4, respectively), WG (28.8 ± 4.4, 32.0 ± 6.5, respectively) or RG (29.0 ± 4.9; 25.3 ± 8.6, respectively). Our data indicate that ZTX seems to be an appropriate general anesthetic for studies that seek to simultaneously quantify the concentration of glycogen and serum biochemical markers without interferences. ZTX is reasonably priced, found easily at veterinary markets, quickly induces deep anesthesia, and presents a low mortality rate.

Induction of Zenk protein expression within the nucleus taeniae of the amygdala of pigeons following tone and shock stimulation

In this study, we evaluated the expression of the Zenk protein within the nucleus taeniae of the pigeon’s amygdala (TnA) after training in a classical aversive conditioning, in order to improve our understanding of its functional role in birds. Thirty-two 18-month-old adult male pigeons (Columba livia), weighing on average 350 g, were trained under different conditions: with tone-shock associations (experimental group; EG); with shock-alone presentations (shock group; SG); with tone-alone presentations (tone group; TG); with exposure to the training chamber without stimulation (context group; CG), and with daily handling (naive group; NG). The number of immunoreactive nuclei was counted in the whole TnA region and is reported as density of Zenk-positive nuclei. This density of Zenk-positive cells in the TnA was significantly greater for the EG, SG and TG than for the CG and NG (P < 0.05). The data indicate an expression of Zenk in the TnA that was driven by experience, supporting the role of this brain area as a critical element for neural processing of aversive stimuli as well as meaningful novel stimuli.

Toxic effects of mercury, lead and gadolinium on vascular reactivity

Heavy metals have been used in a wide variety of human activities that have significantly increased both professional and environmental exposure. Unfortunately, disasters have highlighted the toxic effects of metals on different organs and systems. Over the last 50 years, the adverse effects of chronic lead, mercury and gadolinium exposure have been underscored. Mercury and lead induce hypertension in humans and animals, affecting endothelial function in addition to their other effects. Increased cardiovascular risk after exposure to metals has been reported, but the underlying mechanisms, mainly for short periods of time and at low concentrations, have not been well explored. The presence of other metals such as gadolinium has raised concerns about contrast-induced nephropathy and, interestingly, despite this negative action, gadolinium has not been defined as a toxic agent. The main actions of these metals, demonstrated in animal and human studies, are an increase of free radical production and oxidative stress and stimulation of angiotensin I-converting enzyme activity, among others. Increased vascular reactivity, highlighted in the present review, resulting from these actions might be an important mechanism underlying increased cardiovascular risk. Finally, the results described in this review suggest that mercury, lead and gadolinium, even at low doses or concentrations, affect vascular reactivity. Acting via the endothelium, by continuous exposure followed by their absorption, they can increase the production of free radicals and of angiotensin II, representing a hazard for cardiovascular function. In addition, the actual reference values, considered to pose no risk, need to be reduced.

Association among genetic predisposition, gut microbiota, and host immune response in the etiopathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC), is a chronic disorder that affects thousands of people around the world. These diseases are characterized by exacerbated uncontrolled intestinal inflammation that leads to poor quality of life in affected patients. Although the exact cause of IBD still remains unknown, compelling evidence suggests that the interplay among immune deregulation, environmental factors, and genetic polymorphisms contributes to the multifactorial nature of the disease. Therefore, in this review we present classical and novel findings regarding IBD etiopathogenesis. Considering the genetic causes of the diseases, alterations in about 100 genes or allelic variants, most of them in components of the immune system, have been related to IBD susceptibility. Dysbiosis of the intestinal microbiota also plays a role in the initiation or perpetuation of gut inflammation, which develops under altered or impaired immune responses. In this context, unbalanced innate and especially adaptive immunity has been considered one of the major contributing factors to IBD development, with the involvement of the Th1, Th2, and Th17 effector population in addition to impaired regulatory responses in CD or UC. Finally, an understanding of the interplay among pathogenic triggers of IBD will improve knowledge about the immunological mechanisms of gut inflammation, thus providing novel tools for IBD control.

Cloud computing contribution to manufacturing industry

Manufacturing industry has been always facing challenge to improve the production efficiency, product quality, innovation ability and struggling to adopt cost-effective manufacturing system. In recent years cloud computing is emerging as one of the major enablers for the manufacturing industry. Combining the emerged cloud computing and other advanced manufacturing technologies such as Internet of Things, service-oriented architecture (SOA), networked manufacturing (NM) and manufacturing grid (MGrid), with existing manufacturing models and enterprise information technologies, a new paradigm called cloud manufacturing is proposed by the recent literature. This study presents concepts and ideas of cloud computing and cloud manufacturing. The concept, architecture, core enabling technologies, and typical characteristics of cloud manufacturing are discussed, as well as the difference and relationship between cloud computing and cloud manufacturing. The research is based on mixed qualitative and quantitative methods, and a case study. The case is a prototype of cloud manufacturing solution, which is software platform cooperated by ATR Soft Oy and SW Company China office. This study tries to understand the practical impacts and challenges that are derived from cloud manufacturing. The main conclusion of this study is that cloud manufacturing is an approach to achieve the transformation from traditional production-oriented manufacturing to next generation service-oriented manufacturing. Many manufacturing enterprises are already using a form of cloud computing in their existing network infrastructure to increase flexibility of its supply chain, reduce resources consumption, the study finds out the shift from cloud computing to cloud manufacturing is feasible. Meanwhile, the study points out the related theory, methodology and application of cloud manufacturing system are far from maturity, it is still an open field where many new technologies need to be studied.

Adopting the Vaadin Java framework to rebuild VTT’s Web Interfaces and Database Applications

With the growth in new technologies, using online tools have become an everyday lifestyle. It has a greater impact on researchers as the data obtained from various experiments needs to be analyzed and knowledge of programming has become mandatory even for pure biologists. Hence, VTT came up with a new tool, R Executables (REX) which is a web application designed to provide a graphical interface for biological data functions like Image analysis, Gene expression data analysis, plotting, disease and control studies etc., which employs R functions to provide results. REX provides a user interactive application for the biologists to directly enter the values and run the required analysis with a single click. The program processes the given data in the background and prints results rapidly. Due to growth of data and load on server, the interface has gained problems concerning time consumption, poor GUI, data storage issues, security, minimal user interactive experience and crashes with large amount of data. This thesis handles the methods by which these problems were resolved and made REX a better application for the future. The old REX was developed using Python Django and now, a new programming language, Vaadin has been implemented. Vaadin is a Java framework for developing web applications and the programming language is extremely similar to Java with new rich components. Vaadin provides better security, better speed, good and interactive interface. In this thesis, subset functionalities of REX was selected which includes IST bulk plotting and image segmentation and implemented those using Vaadin. A code of 662 lines was programmed by me which included Vaadin as the front-end handler while R language was used for back-end data retrieval, computing and plotting. The application is optimized to allow further functionalities to be migrated with ease from old REX. Future development is focused on including Hight throughput screening functions along with gene expression database handling

Multicultural Belonging. Individuals across cultures, languages and places

The article-based doctoral dissertation deals with adult individuals in Western societies who were born into multilingual and multicultural families and have parents of different nationalities. The study’s participants grew up outside their parents’ countries of origin and relate to a multitude of bonds that link them across various cultures, languages and places. The study explores the social dimension of cultural belonging and examines diverse approaches that enable the participants to create notions of belonging and identification despite possessing at times contradictory transnational allegiances. The works offers new perspectives on transnational belonging and makes a timely contribution to discussions in the fields of cultural heritage studies, ethnology and transnational studies. The dissertation combines qualitative research methods with an insider perspective. The empirical material is based on semi-structured interviews with fifteen participants, among which are also the author’s siblings. The study addresses the relevance of the author’s personal situatedness and her multi-faceted roles as well as ethical concerns related to the methodological approach of insider research. The social dimension of cultural identities affect both the participants’ identification with their multiple attachments and language use in everyday life. The key research findings present interrelated discussions of the participants’ notion of being a mixture, the importance of family bonds and multilingualism, a specific mixed family lifestyle, the notion of non-belonging and the study participants’ sense of otherness as a means of creating communality with others. The study discusses the participants’ various life strategies of flexible relativising, juggling with multiple affiliations, the approach of “blending in” and their sense of ironic nation-ness for constructing a coherent sense of belonging. The author argues that multicultural belonging is inextricably connected to an association with multiple languages, cultures and places. Multicultural belonging is relational and depends on the context, social relationships and locations. The study proposes that multicultural belonging creates a tolerant understanding of membership and enables experiences of cosmopolitanism and selected notions of allegiance.

Remembering the War and Aggression: A Discourse Analysis of Japan’s State Apologies and Commemoration Speeches on August 15th 1995-2015

Memories of historical injustices affect contemporary politics from local to global level. In East Asia, questions of commemoration and historical responsibility have turned into international and domestic controversies. The main focus has been and still is in apologies conducted by Japanese prime ministers in regards to the war, aggression and colonialism during the era of Imperial Japan. Although it is granted that state apologies are not a crucial part of reconciliation, they can be analysed as a linked but separate process within the context of memory and international relations. The purpose of this study is to examine the discourses of history in Japanese prime ministers’ commemoration speeches on Memorial Ceremony for the War Dead from 1995 to 2015 in order to analyse how the Japanese government is reflecting on its past. In particular, attention is paid on what is being commemorated and how, whether it is the war and its victims or Japan’s post-war era of peace. As an apology is a reciprocal activity, responses from Japan’s most vocal former victims, South Korea and China, were also examined. Discourse analysis was used to identify and examine the different representations of the past. In addition, the apology statements of Japanese prime ministers were analysed in the Many to Many apology framework developed by Tavuchis (1991). Primary material consisted of 21 prime ministers’ speeches from the annual Memorial Ceremony for the War Dead on August 15th and from three apology statements made in 1995, 2005 and 2015. Further international context was primarily collected from newspaper articles of The New York Times and The Times throughout the examined period. It can be concluded from the findings that in the official Japanese remembrance of the past war from 1985’s annexation of Taiwan to the atomic bombings in 1945, both discourses that reinforce apology and remorse over Japan’s past aggressions and discourses that consciously avoid doing so are used. The commemoration speeches and apology statements consistently assert that Japan has acknowledged its past and expresses regret over the acts of aggression. At the same time, the speeches and statements strengthen the narrative that Japan was a victim of circumstances as well as turn the focus on post-war peace-making or on Japan’s own victimhood.

Modularity in Health and Social Services: Perspectives on Organization and Management

Organizations that provide health and social services operate in a complex and constantly changing environment. Changes occur, for example, in ageing, technology and biotechnology, and customers’ expectations, as well as the global economic situation. Organizations typically aim to adapt the changes by introducing new organizational structures and managerial practices, such as process and lean management. Only recently has there been an interest in evaluating whether organizations providing health and social services could apply modularity in order to respond to some of the changes. The concept of modularity originates from manufacturing, but is applied in many other disciplines, such as information technology and logistics. However, thus far, the literature concerning modularity in health and social services is scarce. Therefore the purpose of this thesis is to increase understanding concerning modularity and the possibilities to apply modularity in the health and social services context. In addition, the purpose is to shed light on the viewpoints that are worth taking into account when considering the application of modularity in the health and social services context. The aim of the thesis is to analyze the way in which the modular structures are applied in the health and social services context and to analyze what advantages and possible barriers, as well as managerial concerns, might occur if modularity is applied in the health and social services context. The thesis is conducted by using multiple methods in order to provide a broad aspect to the topic. A systematic literature review provided solid ground for pre-understanding the topic and supported the formulation of the research questions. Theoretical reasoning provided a general overview of the special characteristics of the health and social services context and their effect on application of modularity. Empirical studies concentrated on managerial concerns of modularity particularly from the perspective of health and social services for the elderly. Results of the thesis reveal that structures in products, services, processes, and organizations are rather modular in health and social services. They can be decomposed in small independent units, while the challenges seem to occur especially in the compatibility of the services. It seems that health and social services managers have recognized this problem and they are increasingly paying attention to this challenge in order to enhance the flexible compatibility of services. Advantages and possible barriers of modularity are explored in this thesis, and from the theoretical perspective it could be argued that modularity seems to be beneficial in the context of health and social services. In fact, it has the potential to alleviate several of the challenges that the health and social services context is confronting. For example, modular structures could support organizations in their challenging task to respond to customers’ increasing demand for heterogeneous services. However, special characteristics of the health and social services context create barriers and provide significant challenges in application of modularity. For example, asymmetry of information, negative externalities, uncertainty of demand, and rigid regulation prevent managers from extensively drawing benefits from modularity. Results also reveal that modularity has managerial implications in health and social service. Modularity has the potential to promote and support new service development and outsourcing. Results also provide insights into network management and increases managerial understanding of different network management strategies. Standardization in health and social services is extensive due to legislation and recommendations. Modularity provides alternative paths to take an advantage of standardization while still ensuring the quality of the services. Based on this thesis, it can be concluded, both from a theoretical perspective and from empirical results concerning modularity in health and social services, that modularity might fit well and be beneficial. However, the special characteristics of the health and social services context prevent some of the benefits of modularity and complicate its application. This thesis contributes to the academic literature on the organization and management of health and social services by describing modularity as an alternative way for organizing and managing health and social services. In addition, it contributes to the literature of modularity by exploring the applicability of modularity in the context of health and social services. It also provides practical contribution to health and social services managers by evaluating the pros and cons of modularity when applied to health and social services.

The person inside the nurse : the professional socialization of baccalaureate nursing students

The goal ofthis research was to gain an understanding ofthe process ofprofessional socialization by accessing role meaning ofstudents engaged in a BScN program. Students from each ofthe four years and faculty members from the school ofnursing volunteered as participants. G. Kelly's (1955) Personal Construct Theory provided the framework to determine awareness and constructed meanings. A reflective tool, called LifeMapping, was adapted and utilized to relate student experiences within education that have attributed to nurse role meaning. Focus group interviews verified data interpretation. Students are informed oftheir choice to study nursing through part-time and volunteer work, secondary school cooperative placements. Descriptions reveal that choices are tested and both positive and negative aspects ofthe role observed. Bipolar images of good and bad nurses seem to be context-related. These images may establish biases in choices related to learning experiences. The person inside ofeach aspiring nurse interprets, revises and understands experiences to incorporate individual meaning into their value and belief structures. Students are aware ofchanges and descnbe them as developments that occur personally up to Year ill and role-image changes that begin in Year II. The major difficulty that students encountered was descnbed as negative attitudes towards their anticipated role. Humanistic-interactionist philosophies are echoed in student accounts of learning experiences. Growth and role development corresponds to process factors of small group, problem-base learning.

Enhancing teaching and learning speech acts: action research of Japanese as a foreign language /

This action research observes a second year Japanese class at a university where foreign language courses are elective for undergraduate students. In this study, using the six strategies to teach Japanese speech acts that Ishihara and Cohen (2006) suggested, I conducted three classes and analyzed my teaching practice with a critical friend. These strategies assist learners toward the development of their understanding of the following Japanese speech acts and also keep the learners to use them in a manner appropriate to the context: (I) invitation and refusal; (2) compliments; and (3) asking for a permission. The aim of this research is not only to improve my instruction in relation to second language (L2) pragmatic development, but also to raise further questions and to develop future research. The findings are analyzed and the data derived from my journals, artifacts, students' work, observation sheets, interviews with my critical friend, and pretests and posttests are coded and presented. The analysis shows that (I) after my critical friend encouraged my study and my students gave me some positive comments after each lesson, I gained confidence in teaching the suggested speech acts; (2) teaching involved explaining concepts and strategies, creating the visual material (a video) showing the strategies, and explaining the relationship between the strategy and grammatical forms and samples of misusing the forms; (3) students' background and learning styles influenced lessons; and (4) pretest and posttests showed that the students' Icvel of their L2 appropriate pragmatics dramatically improved after each instruction. However, after careful observation, it was noted that some factors prevented students from producing the correct output even though they understood the speech act differences.

Personal soundtracks on public transit : personal listening devices and socio-spatial negotiations of students' bus journeys

One way of exploring the power of sound in the experience and constitution of space is through the phenomenon of personal listening devices (PLDs) in public environments. In this thesis, I draw from in-depth interviews with eleven Brock University students in S1. Catharines, Ontario, to show how PLDs (such as MP3 players like the iPod) are used to create personalized soundscapes and mediate their public transit journeys. I discuss how my interview participants experience the space-time of public transit, and show how PLDs are used to mediate these experiences in acoustic and non-acoustic ways. PLD use demonstrates that acoustic and environmental experiences are co-constitutive, which highlights a kinaesthetic quality of the transit-space. My empirical findings show that PLDs transform space, particularly by overlapping public and private appropriations of the bus. I use these empirical findings to discuss the PLD phenomenon in the theoretical context of spatiality, and more specifically, acoustic space. J develop the ontological notion of acoustic space, stating that space shares many of the properties of sound, and argue that sound is a rich epistemological tool for understanding and explaining our everyday experiences.

An fMRI study of emotional episodic memory in schizophrenia : effects of diagnosis and sex

La schizophrénie est une psychopathologie largement hétérogène caractérisée entre autres par d’importantes défaillances dans le fonctionnement cognitif et émotionnel. En effet, par rapport à la population générale, forte proportion de ces individus présentent une mémoire déficitaire pour les événements émotionnels. À ce jour, le peu d’études qui se sont penchées sur la mémoire émotionnelle épisodique dans la schizophrénie, ont uniquement mis l’emphase sur l'effet de la valence des stimuli (c’est-à-dire le caractère agréable ou désagréable du stimulus). Toutefois, aucune n’a investigué spécifiquement l’intensité de la réaction aux stimuli (c’est-à-dire une faible par rapport à une forte réaction) malgré quantité de preuves faisant montre, dans la population générale, de différents processus de mémoire émotionnelle pour des stimuli suscitant une forte réaction par rapport à ceux évoquant une faible réponse. Ce manque est d’autant plus flagrant étant donné le nombre d’études ayant rapporté un traitement et un encodage atypiques des émotions spécifiquement au niveau de l’intensité de la réponse subjective chez des patients atteints de schizophrénie. Autre fait important, il est étonnant de constater l’absence de recherches sur les différences de sexe dans la mémoire émotionnelle étant donné l’ensemble des divergences entre hommes et femmes atteints de schizophrénie au niveau de la prévalence, de l’âge de diagnostic, de la manifestation clinique, de l’évolution de la maladie, de la réponse au traitement et des structures cérébrales. Pour pallier à ces lacunes, ce mémoire a évalué : (1) l’effet de la valence des stimuli et de l'intensité de la réaction émotionnelle au niveau des fonctions cérébrales correspondant à la mémoire émotionnelle chez des patients atteints de schizophrénie comparativement à des participants sains; et (2) les possibles différences de sexe dans les processus cérébraux impliqués dans la mémoire émotionnelle chez des patients atteints de schizophrénie par rapport à des volontaires sains. Ainsi, la première étude a comparé les activations cérébrales de patients atteints de schizophrénie par rapport à des participants sains au cours d’une tâche de mémoire émotionnelle dont les stimuli variaient à la fois au niveau de la valence et de l'intensité de la réaction subjective. 37 patients atteints de schizophrénie ainsi que 37 participants en bonne santé ont effectué cette tâche de mémoire émotionnelle lors d’une session d’imagerie par résonance magnétique fonctionnelle (IRMf). Pour toutes les conditions étudiées (images négatives, positives, de faible et de forte intensité), le groupe atteint de schizophrénie a performé significativement moins bien que les volontaires sains. Comparativement aux sujets sains, ils ont montré moins d’activations cérébrales dans les régions limbiques et préfrontales lors de la reconnaissance des images négatives, mais ont présenté un patron d'activations similaire à celui des participants sains lors de la reconnaissance des images chargées positivement (activations observées dans le cervelet, le cortex temporal et préfrontal). Enfin, indépendamment de la valence des stimuli, les deux groupes ont démontré une augmentation des activations cérébrales pour les images de forte intensité par rapport à celles de plus faible intensité. La seconde étude a quant à elle exploré les différences de sexe potentielles au niveau des activations cérébrales associées à la mémoire émotionnelle dans la schizophrénie et dans la population en général. Nous avons comparé 41 patients atteints de schizophrénie (20 femmes) à 41 participants en bonne santé (19 femmes) alors qu’ils effectuaient la même tâche de mémoire émotionnelle mentionnée plus haut. Or, pour cette étude, nous nous sommes concentrés sur les conditions suivantes : la reconnaissance d’images positives, négatives et neutres. Nous n'avons pas observé de différences entre les hommes et les femmes au niveau des performances à la tâche de mémoire pour aucune des conditions. En ce qui a trait aux données de neuroimagerie, comparativement aux femmes en bonne santé, celles atteintes de schizophrénie ont montré une diminution des activations cérébrales dans les régions corticales du système limbique (p. ex. cortex cingulaire moyen) et dans les régions sous-corticales (p. ex. amygdale) lors de la reconnaissance d'images négatives. Pour ce qui est de la condition positive, elles ont présenté, comparativement au groupe de femmes saines, des diminutions d’activations spécifiquement dans le cervelet ainsi que dans le gyrus frontal inférieur et moyen. Les hommes atteints de schizophrénie, eux, ont montré une augmentation d’activations par rapport aux hommes sains dans le gyrus préfrontal médian lors de la reconnaissance des stimuli négatifs ; ainsi que dans les régions pariétales, temporales et limbiques lors de la reconnaissance des stimuli positifs. Dans un autre ordre d’idées, notre analyse corrélationnelle a mis en évidence, chez les femmes, un lien significatif entre l’activité cérébrale et les symptômes au cours de la mémoire des stimuli positifs, alors que chez les hommes atteints schizophrénie, ce lien a été observé au cours de la mémoire des stimuli négatifs. Bref, l’ensemble de nos résultats suggère, chez les patients atteints de schizophrénie, un fonctionnement cérébral atypique spécifiquement lors de la reconnaissance d’images négatives, mais un fonctionnement intact lors de la reconnaissance de stimuli positifs. De plus, nous avons mis en évidence la présence de différences de sexe dans les activations cérébrales associées à la mémoire épisodique émotionnelle soulignant ainsi l'importance d’étudier séparément les hommes et les femmes atteints de schizophrénie dans le cadre de recherches sur les plans cognitif et émotionnel.