Šiame technologijų amžiuje vis daugiau technologijų sąveikauja su aplinka. Tai įvairūs prietaisai, sistemos, robotai, kurie geba apdoroti vaizdinę informaciją ir/arba ją interpretuoti. Kadangi vaizdinė informacija užima labai daug kietojo disko vietos, palyginus su kitokios rūšies informacija, iškyla jos saugojimo bei parsiuntimo problemos. Šioms problemoms spręsti pasitelkiamas duomenų glaudinimas (data compression). Šie sprendimai gali būti įgyvendinti programiškai (software) ir aparatūriškai (hardware). Aparatūriniai sprendimai pasižymi dideliu greičiu taip pat panaudojimo galimybėmis. Kadangi ateityje technologijos vis labiau sąveikaus su aplinka, įrenginiai, sugebantys greitai, tiksliai ir kuo mažesnėmis kietojo disko sąnaudomis apdoroti vaizdus, taps ypač reikšmingi. Tokius įrenginius patogu projektuoti ir tirti naudojantis aparatūros aprašymo kalbomis (angl. Hardware Description Language). Taip pat svarbus šių įrenginių aspektas – vis didėjantis jų sudėtingumas. Pakartotinio naudojimo (reuse) metodologija – naudojimas sukurtų ir verifikuotų komponentų – dabar yra kertinis lustų bei SOC (System On Chip) kūrimo akmuo, kadangi tai yra metodologija, kuri leidžia sudėtingus lustus projektuoti prieinama kaina, geresnės kokybės taip pat taupo žmogiškuosius išteklius ir laiką. / In this age of technological advances more and more technologies interact with environment. It is various devices, systems, robots which are capable to process and/or interpret visual information. Visual information is very space consuming information in comparison with other types of information, so problems like storing, downloading emerges and data compression is trying to resolve these problems. These data compression solutions may be implemented using software or hardware. Hardware solutions characterized with their high speed. In future more and more technologies will be capable to interact with environment, so tools capable of fast, precise and good compression render of images will become very important. These tools may be designed and studied using hardware description languages. Furthermore, visual information processing tools becoming very complex. Reuse methodology enables easier, faster and cheaper design of such tools.

Digital halftoning is a crucial technique used in digital printers to convert a continuoustone image into a pattern of black and white dots. Halftoning is used since printers have a limited availability of inks and cannot reproduce all the color intensities in a continuous image. Error Diffusion is an algorithm in halftoning that iteratively quantizes pixels in a neighborhood dependent fashion. This thesis focuses on the development and design of a parallel scalable hardware architecture for high performance implementation of a high quality Stacked Error Diffusion algorithm. The algorithm is described in ‘C’ and requires a significant processing time when implemented on a conventional CPU. Thus, a new hardware processor architecture is developed to implement the algorithm and is implemented to and tested on a Xilinx Virtex 5 FPGA chip. There is an extraordinary decrease in the run time of the algorithm when run on the newly proposed parallel architecture implemented to FPGA technology compared to execution on a single CPU. The new parallel architecture is described using the Verilog Hardware Description Language. Post-synthesis and post-implementation, performance based Hardware Description Language (HDL), simulation validation of the new parallel architecture is achieved via use of the ModelSim CAD simulation tool.

La maladie cardiovasculaire (MCV) représente encore aujourd’hui l’une des principales causes de décès et d’hospitalisation au Canada. Parmi les facteurs de risque de la MCV, la dyslipidémie est l’un des plus importants. En effet, des concentrations plasmatiques élevées de cholestérol transporté par les lipoprotéines de faibles densités (c-LDL), de triglycérides, ainsi que des concentrations faibles de cholestérol transporté par les lipoprotéines de hautes densités (c-HDL) ont été à maintes reprises identifiées comme des facteurs de risque indépendants de la MCV. Plusieurs facteurs héréditaires et environnementaux ont été associés aux concentrations de lipides plasmatiques. Toutefois, les facteurs héréditaires permettraient d’expliquer la plus grande proportion de la variabilité interindividuelle du bilan lipidique, particulièrement pour le c-HDL. Malgré l’étude de plusieurs millions de modifications génétiques, les principales causes moléculaires responsables de la forte héritabilité des concentrations de c-HDL demeurent pour l’instant encore inconnues. Afin d’expliquer l’héritabilité manquante des concentrations de lipides plasmatiques, plusieurs hypothèses ont été avancées. La présente thèse de doctorat se concentre sur celle suggérant que l’étude de la méthylation de l’ADN, une modification épigénétique considérée comme un facteur héréditaire non traditionnel, permettrait d’identifier de nouveaux fondements moléculaires associés aux dyslipidémies. Dans un premier temps, nous avons analysé la méthylation de l’ADN de plusieurs gènes du métabolisme lipoprotéique chez des sujets atteints d’hypercholestérolémie familiale (HF), un modèle humain de la MCV. Grâce à cette approche, nous avons pu démontrer que la méthylation de l’ADN de plusieurs gènes candidats (ABCA1, ABCG1, CETP, LIPC, LPL et PLTP) était associée à la variabilité du bilan lipidique, ainsi qu’avec les antécédents de maladies coronariennes athérosclérotiques. Dans un deuxième temps, une étude de la méthylation à l’échelle du génome d’un sous-groupe de patients HF nous a permis d’identifier de nouveaux loci associés à la concentration de c-HDL. Nous avons notamment observé que la méthylation de l’ADN du promoteur des gènes TNNT1 et ADRB3 était non seulement associée aux concentrations de c-HDL, mais également avec d’autres facteurs de risque de la MCV. L’ensemble des résultats présentés dans cette thèse démontre que la méthylation de l’ADN contribue à la variabilité du bilan lipidique à jeun de patients atteints d’HF et que l’étude des modifications épigénétiques pourrait aider à expliquer l’héritabilité manquante des concentrations de c-LDL, de c-HDL et de triglycérides plasmatiques.

Studying the biosynthesis, utilization and transport of cholesterol as well as the balance between these pathways may allow us to understand better how to keep its harmful deposition in arteries to a minimum. The goal of my thesis was to identify a novel player, namely the acid sphingomyelinase (ASM), in cellular and plasma cholesterol metabolism by elucidating its regulatory and mechanistic functions. / In our families with high-density lipoprotein-cholesterol (HDL-C) deficiency, one kindred was found to have mutations for the sphingomyelin phosphodiesterase-1 (SMPD-1). This gene codes for lysosomal and secretory ASM and its mutations cause the recessive disorder of Niemann-Pick type A/B (NPD-A/B). My thesis, based on the study of the gene and the protein defect in this family, has led to four important discoveries. First, SMPD-1 mutations are significantly associated with low HDL-C. Second, in order to unveil the mechanism by which ASM contributes to the regulation of HDL-C levels, we investigated the cellular lipid transport in NPD-B fibroblasts. We showed that lysosomal ASM defects lead to co-segregation and co-localization of sphingomyelin (SM) and cholesterol. However, the SM accumulation does not rate-limit the efflux ability of NPD-B cells. Third, we set up the electrospray ionization-mass spectrometry to give an in-depth qualitative and quantitative phospholipid characterization of HDL particles generated from NPD-B. We found that their SM content is significantly elevated. We subsequently provided evidence that the SM content of HDL could be modulated by secretory ASM. Together with other plasma enzymes including lecithin-cholesterol acyl transferase, secretroy ASM appears to regulate the maturation and clearance of HDL-C from the plasma. Finally, we examined the molecular nature of the NPD-B pathophysiology by investigating the structure-function relationship of ASM. We demonstrated that the C-terminal region of ASM plays a critical role in the enzyme conformation that dictates its enzymatic function and secretion. / In summary, our lessons on NPD-B have enabled us to identify ASM as an important player in lipoprotein cholesterol metabolism. Because HDL-C is inversely associated with coronary heart disease, our findings opened a novel therapeutic avenue in the search of preventive strategies against heart disease in our society.

With the severity of cardiovascular disease (CVD) and the related mortality rate to this disease, new methods are necessary for risk assessment and treatment prior to the onset of the disease. The current paradigm in CVD risk assessment has shifted towards the multivariate approach over the individual use of traditional risk factors or lipid measurements. Through a combination of analytical techniques and multivariate statistical analysis, a novel method of cardiovascular risk assessment was developed. The analytical techniques employed include density gradient ultracentrifugation (DGU) and matrix assisted laser desorption ionization mass spectrometry (MALDI-MS) applied to human serum. These techniques provided detailed information about the characterization of the lipoproteins and their structural components, specifically the apolipoproteins belonging to high density lipoproteins (HDL). This information when combined with multivariate statistical analysis provided a method that accurately identified the presence of CVD in clinical studies between cohorts of subjects that had been previously diagnosed with CVD and cohorts of subjects that had been identified as healthy controls (CTRL) based on a clear angiography. The lipoprotein density profiles were divided into subclasses based on their density and measured using a fluorescent probe to tag the lipoprotein particles. Use of multiple ethylenediaminetetraacetic acid (EDTA) based solutes allowed for the manipulation of the density gradient formation in order to separate the lipoproteins by specific density ranges in order to achieve better baseline separation of the profiles. Application of the integrated fluorescence intensities for each subclass of lipoprotein to linear discriminant analysis/sliced inverse regression (LDA/SIR) and quadratic discriminant analysis (QDA) yielded an advanced and accurate form of risk assessment for CVD. This method was found to be highly accurate as well as identify potential atherogenic lipoprotein subclasses through studying the LDA/SIR prediction equation generated. It was also shown that the LDA/SIR equation could be used to monitor medical treatment and lifestyle change for their effects on the risk assessment model. Further study into the atherogenicity of HDL through analysis of the apolipoproteins using MALDI-MS led to identification of potential risk factors that could be added to the statistical analyses. These risk factors included mass differences in the Apolipoprotein A-I (Apo A-I) and Apolipoprotein C-I (Apo C-I) between CVD and CTRL samples as well as the presence of specific mass peaks related to Apolipoprotein A-II (Apo A-II) that were primarily found in the CVD samples. These differences, in addition to the lipoprotein density profile data, were found to increase the potential accuracy of CVD risk assessment. The combination of these methods has shown great potential in the assessment of CVD risk as well as the ability to increase researchers' understanding of the nature of VD and how to treat it.

Thesis (M.Sc.). / Written for the Dept. of Biochemistry. Title from title page of PDF (viewed 2009/06/25). Includes bibliographical references.

Thesis (Ph.D.) -- University of Texas Southwestern Medical Center at Dallas, 2005. / Embargoed. Vita. Bibliography: 92-104.

<p><strong>ABSTRACT</strong></p><p>The demand of healthier products is increasing, and more people are more interested of what they eat. Statistics show that the consumption of snacks is rising.</p><p>Hyperglycemia leads to an increased risk for complications in type II diabetes mellitus. Increased levels of postprandial plasma glucose may also lead to equal or maybe more harmful effects than fasting hyperglycemia. When the levels of postprandial plasma glucose are decreased, the development of cardiovascular complications is delayed, why it is important to lower the snacks consumption especially snacks that brings hunger quickly after they are eaten. Because of these factors, healthier products were developed in this study. The aim was to develop a wafer chocolate product that gives higher satiating effect and healthier blood glucose levels compared to one of Cloetta’s chocolate products. Two raw materials were used, a new carbohydrate and a new fat. The new carbohydrate is a healthier sugar alternative than sucrose, since it leads to lower and prolonged increase in blood glucose and insulin levels. The new fat is based on natural oil that is believed to be healthy, mainly due to its satiating effect. The effects of these two materials on blood glucose response and satiety were examined in two products. Furthermore, the products were made of fat reduced milk chocolate in which sucrose in the chocolate mass was 100 % replaced with the new carbohydrate, dietary fibre and fruit concentrate. Only one of the products contained the new fat. The products, together with Cloetta’s chocolate product were consumed by 17 healthy subjects. Blood glucose response and satiating effect after product intake were examined during a period of 3 days.</p><p>When blood glucose response was analyzed, a slight indication that the products were relatively healthier than placebo, due to placebo’s unhealthy fluctuations, was found. No clear differences regarding blood sugar maxima were found. Placebo showed, as expected, the highest blood glucose maxima and the largest incremental area under curve, but the maxima of the new fat-lacking product was less than half as high as that of the new fatcontaining product and the area was smaller too, which was not expected. The results regarding the hunger levels were not as expected either since the new fat-lacking product was most satiating while the new fatcontaining product was the least satiating. Despite that, 57 % of the subjects reported they would by such products in the future.</p><p>Several biases may have played a role in the results, for example whether or not subjects followed the criteria (e.g. lunch time, exercise), stress, worry, individual energy requirement and how serious and focused the subjects were. However, for further research, increasing the new fat content to 3 g, a bigger sized product, different filling, more subjects and more repeats of same measurements is recommended.</p><p> </p><p> </p> / <p> </p><p><strong><p>SVENSK SAMMANFATTNING</p></strong></p><p>Efterfrågan på hälsosammare produkter ökar, och fler människor blir mer intresserade av vad de äter. Statistik visar att konsumtionen av mellanmål ökar.</p><p>Hyperglykemi leder till en ökad risk för komplikationer i typ II-diabetiker. Ökade nivåer av postprandiell plasmaglukos kan leda till lika eller mer skadliga effekter än fastande hyperglykemi. När nivåerna av postprandiell plasmaglukos är lägre reduceras utvecklingen av kardiovaskulära komplikationer, därför är det viktigt att minska småätandet, speciellt av mellanmål som leder till hunger snart efter att de har ätits. På grund av dessa faktorer har hälsosammare produkter utvecklats i denna studie. Syftet var att utveckla en kexchokladprodukt som har högre mättnadseffekt samt hälsosammare blodsockernivåer jämfört med en av Cloettas chokladprodukter. Två produkter som alternativ till Cloettas chokladprodukter utvecklades. I dessa användes en ny kolhydrat och ett nytt fett. Den nya kolhydraten är ett hälsosammare sockeralternativ än sukros, då den leder till en lägre och förlängd ökning av blodglukos- och insulinnivåer. Det nya fettet är baserat på en naturlig olja som är hälsosam på grund av dess mättande effekt. Effekten av dessa två ämnen undersöktes. Vidare så gjordes de två produkterna av fettreducerad mjölkchoklad i vilken sukros i chokladmassan var 100 % ersatt med den nya kolhydraten, kostfiber samt fruktkoncentrat. endast en av produkterna innehöll det nya fettet. Produkterna, tillsammans med Cloettas chokladprodukt (placebo) konsumerades av 17 friska personer. Blodsockerresponsen och den mättande effekten efter produktintaget undersöktes under 3 timmars period per dag i totalt 3 dagar.</p><p>När blodglukosrespons analyserades hittades en svag indikation på att produkterna var relativt hälsosammare än placebo, på grund av de ohälsosamma fluktuationerna. Inga klara skillnader med avseende på blodsockermaxima hittades. Placebo visade, som väntat, det högsta blodglukosmaximum och den största arean under kurvan, men maximum för produkten utan det nya fettet var mindre än hälften så högt som det för produkten med det nya fettet och även arean under kurvan var mindre, vilket inte var förväntat. De upplevda hungernivåerna var inte heller som förväntat då produkten som saknar det nya fettet mättade flest personer medan produkten innehållande nya fettet mättade minst antal personer. Trots det så kunde 57 % av deltagarna tänka sig köpa sådana produkter i framtiden.</p><p>Flera faktorer kan ha påverkat resultatet, till exempel huruvida försökspersonerna följde kriterierna (t.ex. lunchtid, träning), stress, oro, individuella energibehov samt hur allvarliga och fokuserade personerna var när de angav hungernivåerna. För vidare studier rekommenderas ett högre innehåll av det nya fettet (3 g), en större produkt, annorlunda fruktbaserad fyllning och fler deltagare och flera upprepningar av samma mätningar.</p><p> </p>

Thesis (M.S.)--University of Alabama at Birmingham, 2007. / Title from first page of PDF file (viewed June 30, 2007). Includes bibliographical references (p. 59-65).

The aim of this thesis is to assess the influence of the polyunsaturated fatty acids, especially DHA and EPA in the diet on the animal organism in accordance to the levels of total HDL and LDL cholesterol and triglycerides in plasma. As experimental animals were used rats and they were divided into 3 groups of 10 pieces: control group with the addition of 6 % Carthamus tinctorius (n-6 flares), the group with the addition of 6 % fish oil (n-3: EPA, DHA fish) and the group with 6 % addition of oil from Schizochytrium (n-3: DHA, DHA). After 40 days the animals were putted to death according to relevant regulations. Blood lipids were obtained from blood samples by spectrophotometry. Value of polyunsaturated fatty acids of n-3 and n-6 was set by gas chromatography in the liver, muscle and adipose tissue. In accordance to the increase of content n-3 PUFA in group with fish oil and with oil from Schizochytrium, total and LDL cholesterol was reduced in comparison of samples in control group. In comparison to the control group were TAG reduced only in the group with addition of oil.