Food packaging indicators and sensors

Various categories of food packaging indicators namely; VTT, Ageless Eye, Mocon, Åbo Akademi and Impak were selected and incorporated into food trays manufactured at LUT packaging laboratory. Each of these food packaging indicators was used to investigate (visually and qualitatively) the transmission of oxygen through the seal, and tray material, as well as to detect microbial activity within the content of the package. Applications of different methods of gas flushing, content variation and introduction of two distinct levels of oxygen scavengers were employed as treatments to evaluate the packaging performance of the food packaging indicators. Ease of handling of each food packaging indicator was also taken into considerations. Findings showed that for packages, which contained chicken product, the amount of oxygen in the package, measured immediately after the sealing operation on the first day gradually decreased to zero percent by the third day of the storage period. The oxygen level remained at this point throughout the duration of storage for the chicken packages. Besides, level of oxygen in the packages without product continued to increase with the storage time, at moderate rate of 0.1% for 100%N2 and 0.3% for 30%CO2/70%N2 empty packages. More carbon dioxide gas was recorded for packages flushed with 30%CO2/70%N2. Results also revealed that visual analysis of one of the color indicators for example Ageless Eye, conformed to the data derived from the luminescence food-packaging indicator. This shows that packaging operation of the packaging line was considerably stable, and efficient with negligible exception. However, it was found that most of the food packaging indicators investigated in this research study exhibited considerable packaging challenges, such as, reaction with the content of the package (Impak); over sensitivity (Åbo Akademi and Impak); ease of handling problem (Åbo Akademi); and ease of activation problem (VTT indicators). In this study, the strengths and limitations of different indicators were analyzed. This study demonstrates the applicability of various indicators in MAP using chicken package application.

Koneinvestointien elinkaarikustannusmalli

Työn tavoitteena oli rakentaa käyttökelpoinen elinkaarikustannusmalli, jonka avulla voidaan arvioida investoitavien uusien koneiden elinkaaren aikaisia kustannuksia. Elinkaarikustannusmalli on rakennettu Microsoft Excel -ohjelman avulla. Mallin tavoitteena oli saada tarkempaa tietoa koneiden aiheuttamista elinkaarikustannuksista. Aiemmin tällaista mallia ei ole ollut käytössä, vaan investointien paremmuutta on paljolti verrattu takaisinmaksuajan ja hankintahinnan perusteella. Työssä hyödynnetään investointi- ja elinkaarilaskennan teorioita elinkaarikustannusmallin rakentamiseen. Työn empiirisessä osiossa käydään läpi, miten elinkaarikustannusmalli on rakennettu ja millaisia ominaisuuksia malli sisältää. Empiirisessä osassa myös testataan rakennetun mallin toimivuutta ja lasketaan elinkaarikustannukset yhdelle koneinvestoinnille. Teoriaosuudessa käsiteltiin myös elinkaarituottoja mallin jatkokehityksen kannalta. Työn tuloksena saatiin rakennettua käyttökelpoinen elinkaarikustannusmalli, jonka ominaisuuksina ovat sen helppo käyttö ja yksinkertaisuus. Mallia voidaan käyttää useammalle koneinvestointivaihtoehdolle samanaikaisesti ja sitä voidaan helposti laajentaa tulevaisuudessa.

A forced running wheel system with a microcontroller that provides high-intensity exercise training in an animal ischemic stroke model

We developed a forced non-electric-shock running wheel (FNESRW) system that provides rats with high-intensity exercise training using automatic exercise training patterns that are controlled by a microcontroller. The proposed system successfully makes a breakthrough in the traditional motorized running wheel to allow rats to perform high-intensity training and to enable comparisons with the treadmill at the same exercise intensity without any electric shock. A polyvinyl chloride runway with a rough rubber surface was coated on the periphery of the wheel so as to permit automatic acceleration training, and which allowed the rats to run consistently at high speeds (30 m/min for 1 h). An animal ischemic stroke model was used to validate the proposed system. FNESRW, treadmill, control, and sham groups were studied. The FNESRW and treadmill groups underwent 3 weeks of endurance running training. After 3 weeks, the experiments of middle cerebral artery occlusion, the modified neurological severity score (mNSS), an inclined plane test, and triphenyltetrazolium chloride were performed to evaluate the effectiveness of the proposed platform. The proposed platform showed that enhancement of motor function, mNSS, and infarct volumes was significantly stronger in the FNESRW group than the control group (P<0.05) and similar to the treadmill group. The experimental data demonstrated that the proposed platform can be applied to test the benefit of exercise-preconditioning-induced neuroprotection using the animal stroke model. Additional advantages of the FNESRW system include stand-alone capability, independence of subjective human adjustment, and ease of use.

Experimentation on Wind Powered Hydraulic Heating System

It is common knowledge of the world’s dependency on fossil fuel for energy, its unsustainability on the long run and the changing trend towards renewable energy as an alternative energy source. This aims to cut down greenhouse gas emission and its impact on the rate of ecological and climatic change. Quite remarkably, wind energy has been one of many focus areas of renewable energy sources and has attracted lots of investment and technological advancement. The objective of this research is to explore wind energy and its application in household heating. This research aims at applying experimental approach in real time to study and verify a virtually simulated wind powered hydraulic house heating system. The hardware components comprise of an integrated hydraulic pump, flow control valve, hydraulic fluid and other hydraulic components. The system design and control applies hardware in-the-loop (HIL) simulation setup. Output signal from the semi-empirical turbine modelling controls the integrated motor to generate flow. Throttling the volume flow creates pressure drop across the valve and subsequently thermal power in the system to be outputted using a heat exchanger. Maximum thermal power is achieved by regulating valve orifice to achieve optimum system parameter. Savonius rotor is preferred for its low inertia, high starting torque and ease of design and maintenance characteristics, but lags in power efficiency. A prototype turbine design is used; with power output in range of practical Savonius turbine. The physical mechanism of the prototype turbine’s augmentation design is not known and will not be a focus in this study.

Motivations behind clicking the share-button

The main objective of this study is to examine the motivations behind sharing information and other content in social media. The goal was also to research how social media has changed information sharing behavior online. The theoretical part of the study covers social media marketing, motivations and Rioux’s framework of Information-Acquiring–and-Sharing in Internet environments. Marketer’s abilities to influence information sharing is explained through the MOA-model. The empirical research was conducted by using deductive research methods to assess Rioux’s framework of IA&S behavior in social media. This study included interviews of 12 respondents. The data was collected and analyzed by using qualitative research methods. This study confirms Rioux’s findings. Everyday information needs motivate information acquiring behavior. The findings show that social and emotional needs for maintaining relationships and the need for participation are considered as the most important internal motivations of sharing information and other content on social media. External motivations include expectations of others, environmental norms, and opportunities to win money. Social media strengthens the motivation for sharing information by offering a platform for satisfying these needs. It has also increased information sharing online due to its ease of use.

Marketing a Mobile Application in a Highly Competitive Global Marketplace

The purpose of this research was to study the marketing of mobile applications. The main objective was to find out what are the most efficient ways of marketing to increase the sales for a mobile application within a highly competitive marketplace. The marketplaces, app stores, are studied from the perspective of size, ease of entry, competition and customers and their purchasing process. The study also includes research on what are some of the main marketing methods used in mobile app marketing in general. The study consists of two parts, theoretical and empirical research. Theoretical research was done by studying past scientific research on the chosen subjects. As the subject is very new, the research was also extended to other publications from the field of mobile technology. The empirical part was done through interviews and empirical experiments with a case-company, which were used to answer the main objective of this study. These experiments showed that the chosen methods of mobile app marketing, app store optimization, localization and selected social media marketing activities, created the most sales when used together. Positive results were seen also when the activities were conducted by themselves, but together they were able to push the case company to their all time best results. However the key to succeeding and hitting high positions in the app store rankings would most likely require creating a solid marketing strategy, trying out other marketing activities alongside the ones used here, without forgetting to stay on top of mobile technology trends.

Digitaalisen tarinankerronnan hyödyntäminen peruskouluissa

Työn tavoitteena on selvittää, minkälaisia mahdollisuuksia digitaalinen tarinankerronta antaa peruskouluissa. Työssä käsitellään digitaalinen tarinankerronta ja se, miten sitä hyödynnetään opetuksessa. Työn taustana on opetushallituksen laatima opetussuunnitelma 2016. Opetussuunnitelmassa uutena on ohjelmointi, jota käsitellään työssä vähän tarkemmin. Tulevaisuudessa teknologia, kuten koodaus ja robotiikka sekä lisätty todellisuus voivat tukea luovuutta, innovatiivisuutta ja ongelmanratkaisukykyä. Työ on kirjallisuuskatsaus, jossa aihetta analysoidaan lähdekirjallisuuden avulla. Digitaalisella tarinankerronnalla luokkahuoneessa on rajattomat mahdollisuudet. Digitaalinen tarinankerronta tukee uuden opetussuunnitelman tavoitteita. Digitaalisen tarinankerronnan avulla voidaan osallistaa lapset oppimisprosessiin, heidän omia vahvuuksia saadaan esille sekä he pääsevät itse oivaltamaan ja ratkomaan ongelmia. Ohjelmointi, robotiikka ja lisätty todellisuus antavat uusia työkaluja opetukseen. Ohjelmointi on älyllisesti motivoiva ajattelutapa. Teknologian käyttö opetuksessa lisää opiskelumotivaatiota ja yhdessä tekemisen iloa.

Paremman asiakaskokemuksen ja käytettävyyslähteisen lisäarvon tuottaminen design muutoksilla - tapaustutkimus hyvis.fi järjestelmään

Työn tarkoituksena on antaa Etelä-Karjalan sosiaali- ja terveyspiirin (Eksote) Hyvis –palvelun nettiportaalille muutosehdoituksia koskien nettisivujen ulkoasua, käytettävyyteen liittyviä seikkoja sekä ideoita brändinrakentamiseen verrattuna maailmalta löytyneisiin palkittuihin terveysalan sivustoihin. Työn tavoitteena on löytää mahdollisimman hyvä ohjenuora nettisivujen toiminnallisiin ja ulkoisiin tapoihin sekä käytänteihin, joiden ansiosta brändille voidaan luoda lisäarvoa nettisivujen välityksellä. Työn tuloksina tuli esiin sivujen kategorioinnin tärkeys, jolla voidaan selkeyttää sivujen rakennetta sekä se helpottaa sivuilla navigointia ja tiedonhakua. Kuvien käyttäminen linkkien ja tekstien yhteydessä oli tulosten mukaan suotavaa. Jokainen tarkasteltava sivu sisälsi responsiivisuuden sekä mobiili- ja tablettioptimoinnin, joten se oli yksi tärkeimmistä tutkimuksessa saaduista tuloksista. Sosiaalinen media oli myös kovasti käytössä jokaisen tutkittavan sivun kohdalla.

Cohesion Metrics for Improving Software Quality

Abstract Software product metrics aim at measuring the quality of software. Modu- larity is an essential factor in software quality. In this work, metrics related to modularity and especially cohesion of the modules, are considered. The existing metrics are evaluated, and several new alternatives are proposed. The idea of cohesion of modules is that a module or a class should consist of related parts. The closely related principle of coupling says that the relationships between modules should be minimized. First, internal cohesion metrics are considered. The relations that are internal to classes are shown to be useless for quality measurement. Second, we consider external relationships for cohesion. A detailed analysis using design patterns and refactorings confirms that external cohesion is a better quality indicator than internal. Third, motivated by the successes (and problems) of external cohesion metrics, another kind of metric is proposed that represents the quality of modularity of software. This metric can be applied to refactorings related to classes, resulting in a refactoring suggestion system. To describe the metrics formally, a notation for programs is developed. Because of the recursive nature of programming languages, the properties of programs are most compactly represented using grammars and formal lan- guages. Also the tools that were used for metrics calculation are described.

Ohjelmoinnin opetus peruskoulussa: toiminnallisuutta ja graafista ohjelmointikieltä hyödyntävien opetusmenetelmien vertailu

Ohjelmoinnin opettaminen yleissivistävänä oppiaineena on viime aikoina herättänyt kiinnostusta Suomessa ja muualla maailmassa. Esimerkiksi Suomen opetushallituksen määrittämien, vuonna 2016 käyttöön otettavien peruskoulun opintosuunnitelman perusteiden mukaan, ohjelmointitaitoja aletaan opettaa suomalaisissa peruskouluissa ensimmäiseltä luokalta alkaen. Ohjelmointia ei olla lisäämässä omaksi oppiaineekseen, vaan sen opetuksen on tarkoitus tapahtua muiden oppiaineiden, kuten matematiikan yhteydessä. Tämä tutkimus käsittelee yleissivistävää ohjelmoinnin opetusta yleisesti, käy läpi yleisimpiä haasteita ohjelmoinnin oppimisessa ja tarkastelee erilaisten opetusmenetelmien soveltuvuutta erityisesti nuorten oppilaiden opettamiseen. Tutkimusta varten toteutettiin verkkoympäristössä toimiva, noin 9–12-vuotiaille oppilaille suunnattu graafista ohjelmointikieltä ja visuaalisuutta tehokkaasti hyödyntävä oppimissovellus. Oppimissovelluksen avulla toteutettiin alakoulun neljänsien luokkien kanssa vertailututkimus, jossa graafisella ohjelmointikielellä tapahtuvan opetuksen toimivuutta vertailtiin toiseen opetusmenetelmään, jossa oppilaat tutustuivat ohjelmoinnin perusteisiin toiminnallisten leikkien avulla. Vertailututkimuksessa kahden neljännen luokan oppilaat suorittivat samankaltaisia, ohjelmoinnin peruskäsitteisiin liittyviä ohjelmointitehtäviä molemmilla opetus-menetelmillä. Tutkimuksen tavoitteena oli selvittää alakouluoppilaiden nykyistä ohjelmointiosaamista, sitä minkälaisen vastaanoton ohjelmoinnin opetus alakouluoppilailta saa, onko erilaisilla opetusmenetelmillä merkitystä opetuksen toteutuksen kannalta ja näkyykö eri opetusmenetelmillä opetettujen luokkien oppimistuloksissa eroja. Oppilaat suhtautuivat kumpaankin opetusmenetelmään myönteisesti, ja osoittivat kiinnostusta ohjelmoinnin opiskeluun. Sisällöllisesti oppitunneille oli varattu turhan paljon materiaalia, mutta esimerkiksi yhden keskeisimmän aiheen, eli toiston käsitteen oppimisessa aktiivisilla leikeillä harjoitellut luokka osoitti huomattavasti graafisella ohjelmointikielellä harjoitellutta luokkaa parempaa osaamista oppitunnin jälkeen. Ohjelmakoodin peräkkäisyyteen liittyvä osaaminen oli neljäsluokkalaisilla hyvin hallussa jo ennen ohjelmointiharjoituksia. Aiheeseen liittyvän taustatutkimuksen ja luokkien opettajien haastatteluiden perusteella havaittiin koulujen valmiuksien opetussuunnitelmauudistuksen mukaiseen ohjelmoinnin opettamiseen olevan vielä heikolla tasolla.

Interoperability for IoT Health Systems Using HL7 Standard

Internet of Things or IoT is revolutionizing the world we are living in, similarly the way Internet and the web did few decades ago. It is changing how we interact with the things surrounding us. Electronic health and remote patient monitoring are the ways of utilizing these technological improvements towards the healthcare. There are many applications of IoT in eHealth such as, it will open the gate to provide healthcare to the remote areas of the world, where healthcare through traditional hospital systems cannot be provided. To connect these new eHealth IoT systems with the existing healthcare information systems, we can use the existing interoperability standards commonly used in healthcare information systems. In this thesis we implemented an eHealth IoT system based on Health Level 7 interoperability standard for continuous data transmission. There is not much previous work done in implementing the HL7 for continuous sensor data transmission. Some of the previous work was limited to sensors which are not continuous in nature and some of it is only theatrical architecture. This thesis aims to prove that it is possible to implement an eHealth IoT system by using sensors which require continues data transmission, such as respiratory sensors, and to connect it with the existing eHealth information system semantically by using HL7 interoperability standard. This system will be beneficial in implementing eHealth IoT systems for those patients, who requires continuous healthcare personal monitoring. This includes elderly people and patients, whose health need to be monitored constantly. To implement the architecture, HL7 v2.5 is selected due to its ease of implementation and low size. We selected some open source technologies because of their open licenses and large developer community. We will also review the most efficient technology available in every layer of eHealth IoT system and will propose an efficient system.

Attractive silences in cricket courtship song : mate choice using a short-range signal /

Matings systems using signals for sexual communication have been studied extensively and results commonly suggest that females use these signals for locating males, species-identification, and mate choice. Although numerous mating systems employ multiple signals, research has generally focused on long-range signals perhaps due to their prominence and ease of study. This study focused on the short-range acoustic courtship song of crickets. The results presented here suggest this signal is under selection by female choice. Females mated preferentially with males having shorter silences between the two types of ticks within the song. The length of these silences (Gap 1) was correlated with male condition such that males having long silences were significantly lower in mass with respect to body size when compared to males having short silences. Both Gap 1 length and male condition were significantly repeatable within males over time suggesting the possibility these traits have a genetic basis. This study is the first empirical study to test female preferences within the natural variation of the courtship song. It now appears, at least in crickets, that both the longand short-range signals of a multi-signal mating system may contribute to male mating success.

Chelated fluoroboron cations : synthesis and multinuclear nmr studies

The preparation of chelated difluoroboron cations (DD)BF2+, where DD is a saturated polydentate tertiary-amine or polydentate aromatic ligand, has been systematically studied by using multinuclear solution and solid state nuclear magnetic resonance spectroscopy and fast atom bombardment mass spectrometry. Three new methods of synthesis of (DD)BF2+ cations are reported, and compared with the previous method of reacting a chelating donor with Et20.BF3. The methods most effective for aromatic donors such as 1,1O-phenanthroline are ineffective for saturated polydentate tertiary-amines like N,N,N' ,Nil ,Nil-pentamethyldiethylenetriamine. Polydentate tertiary-amine donors that form 5-membered rings upon bidentate chelation were found to chelate effectively when the BF2 source contained two leaving groups (a heavy halide and a Lewis base such as pyridine =pyr or isoxazole =ISOX), i.e., pyr.BF2X (X = CI or Br), ISOX.BF2X and (pyr)2BF2+. Those that would form 6membered rings upon chelation do not chelate by any of the four methods. Polydentate aromatic ligands chelate effectively when the BF2 source contained a weak Lewis base, e.g., ISOX.BF3, ISOX.BF2X and Et20.BF3. Bidentate chelation by polydentate tertiaryamine and aromatic donors leads to nmr parameters that are significantly different then their (D)2BF2+ relatives (D =monod~ntate t-amines or pyridines). The chelated haloboron cations (DD)BFCI+, and (DD)BFBr+ were generated from D.BFX2 adducts for all ligands that form BF2+ cations above. In addition, the (DD)BCI2+ and (DD)BBr2+ cations were formed from D.BX3 adducts by the chelating aromatic ligands, except for the aromatic ligand 1,8-bis(dimethylamino)naphthalene, which formed only the (DD)BF2+ cation, apparently due to its extreme steric hindrance. Chelation by a donor is a two-step reaction. For polydentate tertiary-amine ligands, the two rates appear to be very dependent on the two possible leaving groups on the central boron atom. The order of increasing ease of displacement for the donors was: pyr < Cl < Br < ISOX. The rate of chelation by polydentate aromatic ligands appears to be dependent on the displacement of the first ligand from the boron. The order of increasing ease of displacement for the donors was: pyr < CI < ISOX ~ Br < Et20.

METHOXYPYRAZINES AND LADYBUG TAINT IN WINES

Methoxypyrazines are aroma active compounds found in many wine varietals. These compounds can be of either grape-derived nature or can be introduced into wines via Coccinellidae beetles. Regardless of their origin, methoxypyrazines can have either a beneficial role for wine quality, contributing to the specificity of certain wine varietals (Cabernet sauvignon, Cabernet franc, Sauvignon blanc) or a detrimental role, particularly at higher concentrations, resulting in overpowering green, unripe and herbaceous notes. When methoxypyrazines of exogenous nature are responsible for these unpleasant characteristics, wines are considered to be affected by what is generally known as Ladybug taint (LBT). This is work is a collection of studies seeking to create a sensitive analytical method for the detection and quantification of methoxypyrazines in wines; to investigate the role of different Coccinellidae species in the tainting of wines with LBT and identify the main compounds in ladybug tainted wines responsible for the typical green herbaceous characteristics; to determine the human detection threshold of 2,5-dimethyl-3-methoxypyrazine in wines as well as investigate its contribution to the aroma of wines; and finally to survey methoxypyrazine concentrations in a large set of wines from around the world. In the first study, an analytical method for the detection and quantitation of methoxypyrazines in wines was created and validated. The method employs multidimensional Gas Chromatography coupled with Mass Spectrometry to detect four different methoxypyrazines (2,5-dimethyl-3-methoxypyrazine, isobutyl methoxypyrazine, secbutyl methoxypyrazine and isopropyl methoxypyrazines) in wine. The low limits of detection for the compounds of interest, improved separation and isolation capabilities, good validation data, as well as the ease of use recommend this method as a good alternative to the existing analytical methods for methoxypyrazine detection in wine. In the second study the capacity of two Coccinellidae species, found in many wine regions – Harmonia axyridis and Coccinella septempunctata - to taint wines is evaluated. Coccinella septempunctata is shown to be as capable as causing LBT in wines as Harmonia axyridis. Dimethyl methoxypyrazine, previously thought to be of exogenous nature only (from Coccinellidae haemolymph), is also detected in control (untainted) wines. The main odor active compounds in LBT wines are investigated through Aroma Extract Dilution Assay. These compounds are identified as isopropyl methoxypyrazine, sec- and iso- butyl methoxypyrazine. In the third study, the human detection threshold for dimethyl methoxypyrazine in wine is established to be 31 ng/L in the orthonasal modality and 70 ng/L retronasally. After wines spiked with various amounts of dimethyl methoxypyrazine are evaluated sensorally, dimethyl methoxypyrazine causes significant detrimental effects to wine aroma at a concentration of 120 ng/L. The final study examines methoxypyrazine (dimethyl methoxypyrazine, isopropyl methoxypyrazine, secbutyl methoxypyrazine and isobutyl methoxypyrazine) concentrations in 187 wines from around the world. Dimethyl methoxypyrazine is detected in the majority of the red wines tested. Data are interpreted through statistical analyses. A new measure for predicting greenness/herbaceousness in wines - methoxypyrazine “total impact factor” is proposed.

Cardiologie nucléaire du 21ième siècle : nouveautés et réalités

Les maladies cardio-vasculaires demeurent une cause majeure de mortalité et morbidité dans les sociétés développées. La recherche de déterminants prédictifs d’évènements vasculaires représente toujours un enjeu d’actualité face aux coûts croissants des dépenses reliées aux soins médicaux et à l’élargissement des populations concernées, notamment face à l’occidentalisation des pays émergeants comme l’Inde, le Brésil et la Chine. La cardiologie nucléaire occupe depuis trente ans, une place essentielle dans l’arsenal des méthodes diagnostiques et pronostiques des cardiopathies. De plus, de nouvelles percées permettront de dépister d’une façon plus précoce et précise, la maladie athérosclérotique cardiaque et périphérique chez les populations atteintes ainsi qu’en prévention primaire. Nous présenterons dans cette thèse, deux approches nouvelles de la cardiologie nucléaire. La dysfonction endothéliale est considérée comme le signal pathologique le plus précoce de l’athérosclérose. Les facteurs de risques cardiovasculaires traditionnels atteignent la fonction endothéliale et peuvent initier le processus d’athérosclérose même en l’absence de lésion endothéliale physique. La quantification de la fonction endothéliale coronarienne comporte donc un intérêt certain comme biomarqueur précoce de la maladie coronarienne. La pléthysmographie isotopique, méthodologie développée lors de ce cycle d’étude, permet de quantifier la fonction endothéliale périphérique, cette dernière étant corrélée à la fonction endothéliale coronarienne. Cette méthodologie est démontrée dans le premier manuscrit (Harel et. al., Physiol Meas., 2007). L’utilisation d’un radiomarquage des érythrocytes permet la mesure du flot artériel au niveau du membre supérieur pendant la réalisation d’une hyperémie réactive locale. Cette nouvelle procédure a été validée en comparaison à la pléthysmographie par jauge de contrainte sur une cohorte de 26 patients. Elle a démontré une excellente reproductibilité (coefficient de corrélation intra-classe = 0.89). De plus, la mesure du flot artérielle pendant la réaction hyperémique corrélait avec les mesure réalisées par la méthode de référence (r=0.87). Le deuxième manuscrit expose les bases de la spectroscopie infrarouge comme méthodologie de mesure du flot artériel et quantification de la réaction hyperémique (Harel et. al., Physiol Meas., 2008). Cette étude utilisa un protocole de triples mesures simultanées à l’aide de la pléthysmographie par jauge de contrainte, radio-isotopique et par spectroscopie infrarouge. La technique par spectroscopie fut démontrée précise et reproductible quant à la mesure des flots artériels au niveau de l’avant-bras. Cette nouvelle procédure a présenté des avantages indéniables quant à la diminution d’artéfact et à sa facilité d’utilisation. Le second volet de ma thèse porte sur l’analyse du synchronisme de contraction cardiaque. En effet, plus de 30% des patients recevant une thérapie de resynchronisation ne démontre pas d’amélioration clinique. De plus, ce taux de non-réponse est encore plus élevé lors de l’utilisation de critères morphologiques de réponse à la resynchronisation (réduction du volume télésystolique). Il existe donc un besoin urgent de développer une méthodologie de mesure fiable et précise de la dynamique cardiaque. Le troisième manuscrit expose les bases d’une nouvelle technique radio-isotopique permettant la quantification de la fraction d’éjection du ventricule gauche (Harel et. al. J Nucl Cardiol., 2007). L’étude portant sur 202 patients a démontré une excellente corrélation (r=0.84) avec la méthode de référence (ventriculographie planaire). La comparaison avec le logiciel QBS (Cedar-Sinai) démontrait un écart type du biais inférieur (7.44% vs 9.36%). De plus, le biais dans la mesure ne démontrait pas de corrélation avec la magnitude du paramètre pour notre méthodologie, contrairement au logiciel alterne. Le quatrième manuscrit portait sur la quantification de l’asynchronisme intra-ventriculaire gauche (Harel et. al. J Nucl Cardiol, 2008). Un nouveau paramètre tridimensionnel (CHI: contraction homogeneity index) (médiane 73.8% ; IQ 58.7% - 84.9%) permis d’intégrer les composantes d’amplitude et du synchronisme de la contraction ventriculaire. La validation de ce paramètre fut effectuée par comparaison avec la déviation standard de l’histogramme de phase (SDΦ) (médiane 28.2º ; IQ 17.5º - 46.8º) obtenu par la ventriculographie planaire lors d’une étude portant sur 235 patients. Ces quatre manuscrits, déjà publiés dans la littérature scientifique spécialisée, résument une fraction des travaux de recherche que nous avons effectués durant les trois dernières années. Ces travaux s’inscrivent dans deux axes majeurs de développement de la cardiologie du 21ième siècle.