Two-way FSI modelling of blood flow through CCA accounting on-line medical diagnostics in hypertension

Flow parameters can induce pathological changes in the arteries. We propose a method to asses those parameters using a 3D computer model of the flow in the Common Carotid Artery. Input data was acquired using an automatic 2D ultrasound wall tracking system. This data has been used to generate a 3D geometry of the artery. The diameter and wall thickness have been assessed individually for every patient, but the artery has been taken as a 75mm straight tube. The Young’s modulus for the arterial walls was calculated using the pulse pressure, diastolic (minimal) diameter and wall thickness (IMT). Blood flow was derived from the pressure waveform using a 2-parameter Windkessel model. The blood is assumed to be non-Newtonian. The computational models were generated and calculated using commercial code. The coupling method required the use of Arbitrary Lagrangian-Euler formulation to solve Navier-Stokes and Navier-Lamè equations in a moving domain. The calculations showed that the distention of the walls in the model is not significantly different from the measurements. Results from the model have been used to locate additional risk factors, such as wall shear stress or circumferential stress, that may predict adverse hypertension complications

Approximated Shell Model based on Additive Decomposition of Deformation Gradient

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Oncogenic R132 IDH1 Mutations Limit NADPH for De Novo Lipogenesis through (D)2-Hydroxyglutarate Production in Fibrosarcoma Sells.

Neomorphic mutations in NADP-dependent isocitrate dehydrogenases (IDH1 and IDH2) contribute to tumorigenesis in several cancers. Although significant research has focused on the hypermethylation phenotypes associated with (D)2-hydroxyglutarate (D2HG) accumulation, the metabolic consequences of these mutations may also provide therapeutic opportunities. Here we apply flux-based approaches to genetically engineered cell lines with an endogenous IDH1 mutation to examine the metabolic impacts of increased D2HG production and altered IDH flux as a function of IDH1 mutation or expression. D2HG synthesis in IDH1-mutant cells consumes NADPH at rates similar to de novo lipogenesis. IDH1-mutant cells exhibit increased dependence on exogenous lipid sources for in vitro growth, as removal of medium lipids slows growth more dramatically in IDH1-mutant cells compared with those expressing wild-type or enzymatically inactive alleles. NADPH regeneration may be limiting for lipogenesis and potentially redox homeostasis in IDH1-mutant cells, highlighting critical links between cellular biosynthesis and redox metabolism

Trends in prevalence of hepatitis B virus infection among Albanian blood donors, 1999-2009

<p>Abstract</p> <p>Background</p> <p>Hepatitis B virus (HBV) was among the first virus known to be transmitted by blood and blood productions. The objective of this study is to determine the trend of hepatitis B virus in blood donors.</p> <p>Materials and methods</p> <p>In this study 79274 blood donors were retrospectively evaluated for HBsAg. The donors were selected using personal questionnaire, physical examination and testing blood before donation. Blood banks records are used as source of information. The blood donors samples were analyzed for the presence of hepatitis B surface antigen (HBsAg) by commercial available kits ELISA method, third generation (from Abbott laboratory, Germany). A sample was considered as HBsAg positive when found twice repeatedly reactive. Reactive samples were not confirmed with addition tests.</p> <p>Results</p> <p>In the evaluation data, we found out that from 79274 of the total healthy blood donors, 15983 were voluntary donors, 52876 were family replacement donors and 10424 commercial blood donors. The prevalence of HBsAg in blood donors was 7.9%. It was increased steadily from 5.9% in 1999 to 9.1% in 2006 and decreased in 7.9% in 2009. According to blood donors status the HBsAg prevalence was 10.5% in commercial blood donors, 8.1% in voluntary donors and 8.6% in family replacement donors. The prevalence of anti-HBc in blood donors was 59.1%.</p> <p>Conclusion</p> <p>The prevalence of HBsAg was lower in voluntary non remunerate blood donors than commercial donors and family replacement blood donors. In FDs the prevalence was higher than VDs but lower than CDs. So, it is important to encourage the voluntary blood donors to become regularly blood donors.</p

Anaerobic digestion and gasification of seaweed

The potential of algal biomass as a source of liquid and gaseous biofuels is a highly topical theme, with over 70 years of sometimes intensive research and considerable financial investment. A wide range of unit operations can be combined to produce algal biofuel, but as yet there is no successful commercial system producing such biofuel. This suggests that there are major technical and engineering difficulties to be resolved before economically viable algal biofuel production can be achieved. Both gasification and anaerobic digestion have been suggested as promising methods for exploiting bioenergy from biomass, and two major projects have been funded in the UK on the gasification and anaerobic digestion of seaweed, MacroBioCrude and SeaGas. This chapter discusses the use of gasification and anaerobic digestion of seaweed for the production of biofuel

Energy – conversion, conservation and management

Energy is an abstract notion that helps to understand the nature and contributes to the creation of the civilization. The energy notion has a huge meaning not only due to practical reason – it is essential for economy and philosophy too. It turns out that in Hellenic philosophy, and especially in its fundamental part, i.e., metaphysics, there is no place for the concepts and methods of reasoning developed by physics and chemistry. Philosophy assumes that most of the physical and chemical concepts are not known in nature in spe these are employed by science only as a kind of mental keys (qualitative occultea) for the description and understanding of the universe. The concept of energy is only one example of a notion accepted both by the philosophers (in its metaphysical sense) and physicians (in its descriptive role)

Clean gas technologies - towards zero-emission repowering of Pomerania

In the paper a brief review of processes for energy conversion developed recently within the framework of clean gas te chnologies is presented, in cluding projects for future repowering of Pomerania. The main aim of this work is to show the diferent thermodynamcs cycles which improve efficiency and/or decrease emissions such as: Cheng cycle, Szewalski cycle, LOTHECO cycle, hybrid pSOFC/GT cycle, inverse Brayton cycle, low-emission cycle and zero-emission cycle. For that purpose,cycles and results of analysis are frst studied and, secondly, new concept is presented. The role of coupled analysis 0D and 3D in cycle's devices is also discussed

Starty bloków energetycznych we współpracy z odnawialnymi źródłami energii

The article presents the development trends in the electricity generation market. Attention is paid to the strongly developing renewable energy sources (RES). For example, results developed for the power sector in Germany are quoted. Besides undoubted gains from such power sector development, also pointed out are some risks for conventional power generation, due to the nature of operation of these two generation modes. Based on the results of an analysis of the body of a high-power steam turbine’s HP part, a way of creating cooperation and mutual complementarity of these two types of generation sources is presented. To determine the conditions for this cooperation, the results of numerical simulation with elastic-plastic adaptations of the material were used. This branch of mechanical engineering, with numerous applications in other industries, has not found any deeper application in the energy sector, even though the Polish school of elasticity had the leading status in the world and is still recognized today. Appropriate application of the shakedown phenomenon enables faster starts, and hence the mutual coexistence of large steam units with developing renewable energy farms, whose outputs are strongly dependent on weather conditions.W artykule zaprezentowano trendy rozwojowe rynku wytwarzania energii elektrycznej. Zwrócono przy tym uwagę na silnie rozwijającą się energetykę odnawialną (OZE). Dla przykładu przytoczono wyniki opracowane dla energetyki niemieckiej. Oprócz niewątpliwych zysków z takiego rozwoju energetyki wskazano również na pewne zagrożenia dla energetyki konwencjonalnej, wynikające ze specyfiki pracy tych dwóch gałęzi wytwarzania. Na podstawie wyników analizy korpusu części WP turbiny parowej dużej mocy zaprezentowano sposób kreowania współpracy i wzajemnego uzupełniania tych dwóch źródeł wytwarzania. Dla określenia warunków, jakim winna podlegać ta współpraca, posłużono się wynikami symulacji numerycznej wykorzystującej adaptacje sprężysto- plastyczne materiału. Ten dział mechaniki, mający swobodne zastosowanie w innych działach przemysłu, w energetyce nie znalazł głębszych aplikacji, pomimo że polska szkoła plastyczności miała status wiodącej w świecie i jest rozpoznawalna do dziś. Poprawne zastosowanie zjawiska shakedownu umożliwiłoby szybsze starty, a tym samym wzajemną koegzystencję dużych bloków parowych z rozwijającymi się farmami OZE, których moce wytwórcze silnie zależą od warunków pogodowych