Atrioventricular and interventricular delay optimization in cardiac resynchronization therapy: physiological principles and overview of available methods

In this review, the physiological rationale for atrioventricular and interventricular delay optimization of cardiac resynchronization therapy is discussed including the influence of exercise and long-term cardiac resynchronization therapy. The broad spectrum of both invasive and non-invasive optimization methods is reviewed with critical appraisal of the literature. Although the spectrum of both invasive and non-invasive optimization methods is broad, no single method can be recommend for standard practice as large-scale studies using hard endpoints are lacking. Current efforts mainly investigate optimization during resting conditions; however, there is a need to develop automated algorithms to implement dynamic optimization in order to adapt to physiological alterations during exercise and after anatomical remodeling

Methodology of calculation of construction and hydrodynamic parameters of a foam layer apparatus for mass-transfer processes

Промислова реалізація методу стабілізації газорідинного шару дозволяє значно розширити галузь застосування пінних апаратів і відкриває нові можливості інтенсифікації технологічних процесів з одночасним створенням маловідходних технологій. У статті встановлені основні параметри, що впливають на гідродинаміку пінних апаратів, розглянуті основні конструкції та режими роботи пінних апаратів. Виявлено зв'язок гідродинамічних параметрів. Розглянуто гідродинамічні закономірності пінного шару. Вказані фактори, що впливають на процес масообміну, як в газовій, так і в рідкій фазах. Проведений аналіз ряду досліджень показав, що перспективним напрямком інтенсифікації процесу масообміну є розробка апаратів з трифазним псевдозрідженим шаром зрошуваної насадки складних форм із сітчастих матеріалів. Отже, необхідне проведення спеціальних досліджень гідродинамічних режимів роботи апарату з сітчастою насадкою і визначенням параметрів, що впливають на швидкість переходу насадки з одного режиму в інший.Industrial implementation of the stabilization method of the gas-liquid layer can significantly expand the field of use of foaming apparatus and opens up new opportunities for intensifying technological processes with the simultaneous creation of low-waste technologies. The article establishes the basic parameters influencing the hydrodynamics of foam apparatus, considers the basic constructions and operating modes of foam apparatus. The connection of hydrodynamic parameters is revealed. The hydrodynamic laws of the foam layer are considered. The indicated factors affecting the process of mass transfer, both in the gas and in the liquid phases. The conducted analysis of a number of studies showed that the perspective direction of intensification of the mass transfer process is the development of apparatuses with a three-phase fluidized bed of an irrigated nozzle of complex forms with mesh materials

Partitioning and distribution of RAPD variation in a set of populations of the Medicago sativa complex

Lucerne (Medicago sativa) is a major perennial forage legume and includes two main sub-species. The variation available within a group of 26 tetraploid populations of this complex was investigated with random amplified polymorphic DNA (RAPD) markers. Thirty seedlings per population were analysed. Twenty-nine reproducible markers, 24 being polymorphic, were obtained with four primers. The variation partitioning was studied using the AMOVA technique. The genetic variation proved to be nearly equally distributed within and between populations. The between-population variation was further partitioned between groups (falcata, Flemish, mediterranean) and between populations within groups. The latter source of variation was the major one. Although this study included a sub-species level, the within-population variation was very large probably due to the outcrossing reproduction and the tetraploidy. A similar approach was used to distinguish varieties and proved to be very efficient. The within-population dissimilarity indices were very variable according to the populations; the falcata and Flemish-type materials showed on average a larger within-population dissimilarity. The between-population dissimilarities were calculated and a dendrogram was drawn. This made it possible to separate the populations belonging to the two sub-species and the populations of subspecies sativa largely introgressed by falcata. The relationships among the sativa populations partly fitted with the known origin of the material or with their agronomic behaviour.Variation intra- et inter-population et relations entre populations du complexe Medicago sativa mises en évidence à l'aide de marqueurs RAPD. La luzerne (Medicago sativa) est une légumineuse fourragère majeure comprenant deux sous-espèces principales, sativa et falcata. La variation disponible au sein d'un ensemble de 26 populations tétraploïdes de ce complexe a été analysée à l'aide de marqueurs RAPD (random amplified polymorphic DNA). Trente plantules par population ont été étudiées. Vingt-neuf marqueurs reproductibles dont 24 marqueurs polymorphes ont été mis en évidence à l'aide de quatre amorces. La variation génétique qui a été étudiée à l'aide de la technique Amova est distribuée de façon presque égale au sein des populations et entre les populations. La variation inter-population a été répartie en variation inter-groupes (falcata, flamand et méditerranéen) et entre populations au sein des groupes. Cette dernière source de variation est la plus importante. Bien que cette étude ait pris en compte la variation d'origine sous-spécifique, l'importante variation intra-population est vraisemblablement liée à la reproduction allogame et à l'autotétraploïdie de la luzerne pérenne. La même technique a été utilisée pour étudier la distinction entre les variétés et s'avère très performante pour cela. La dissimilarité intrapopulation varie selon la population, les populations dormantes et de type flamand, montrant en moyenne une plus grande dissimilarité intrapopulation. Les dissimilarités interpopulation ont été calculées et un dendrogramme a été tracé pour cet indice de distance. Il permet de séparer les populations des deux sous-espèces ainsi que les populations sativa fortement introgressées de falcata. Les relations entre les populations sativa correspondent partiellement à l'origine du matériel et à son comportement agronomique

Feral genetically modified herbicide tolerant oilseed rape from seed import spills: are concerns scientifically justified?

One of the concerns surrounding the import (for food and feed uses or processing) of genetically modified herbicide tolerant (GMHT) oilseed rape is that, through seed spillage, the herbicide tolerance (HT) trait will escape into agricultural or semi-natural habitats, causing environmental or economic problems. Based on these concerns, three EU countries have invoked national safeguard clauses to ban the marketing of specific GMHT oilseed rape events on their territory. However, the scientific basis for the environmental and economic concerns posed by feral GMHT oilseed rape resulting from seed import spills is debatable. While oilseed rape has characteristics such as secondary dormancy and small seed size that enable it to persist and be redistributed in the landscape, the presence of ferals is not in itself an environmental or economic problem. Crucially, feral oilseed rape has not become invasive outside cultivated and ruderal habitats, and HT traits are not likely to result in increased invasiveness. Feral GMHT oilseed rape has the potential to introduce HT traits to volunteer weeds in agricultural fields, but would only be amplified if the herbicides to which HT volunteers are tolerant were used routinely in the field. However, this worst-case scenario is most unlikely, as seed import spills are mostly confined to port areas. Economic concerns revolve around the potential for feral GMHT oilseed rape to contribute to GM admixtures in non-GM crops. Since feral plants derived from cultivation (as distinct from import) occur at too low a frequency to affect the coexistence threshold of 0.9% in the EU, it can be concluded that feral GMHT plants resulting from seed import spills will have little relevance as a potential source of pollen or seed for GM admixture. This paper concludes that feral oilseed rape in Europe should not be routinely managed, and certainly not in semi-natural habitats, as the benefits of such action would not outweigh the negative effects of management

Parâmetros dopplervelocimétricos na avaliação da perviedade da anastomose portossistêmica intra-hepática transjugular (TIPS) Dopplerflowmetric patterns for evaluation of transjugular intrahepatic portosystemic shunt patency

A anastomose portossistêmica intra-hepática transjugular (TIPS) é um procedimento intervencionista minimamente invasivo realizado pela introdução de prótese metálica auto-expansível no parênquima hepático, via transjugular. Tem por objetivo tratar as complicações da hipertensão portal, principalmente a hemorragia digestiva alta e a ascite refratária. A estenose é complicação freqüente, embora o procedimento seja eficaz e com baixo índice de insucesso. O diagnóstico precoce da estenose é de fundamental importância, pois interfere no tipo de tratamento a ser realizado e o reaparecimento dos sintomas pode ser grave. O ultra-som Doppler é então utilizado para o seguimento dos pacientes portadores do TIPS, e vários parâmetros são descritos na literatura para o diagnóstico de estenose, como: as velocidades mínima e máxima no interior da prótese, a velocidade na veia porta, o gradiente de velocidade entre dois pontos da prótese, e outros. Infelizmente não há consenso sobre qual parâmetro ou conjunto de parâmetros é mais eficaz no diagnóstico, porque os protocolos de avaliação variam de instituição para instituição. Os autores realizaram uma revisão dos parâmetros de estenose descritos na literatura e de outros aspectos de fundamental importância na compreensão do procedimento, como as indicações, as contra-indicações e a fisiopatologia da estenose.<br>Transjugular intrahepatic portosystemic shunt (TIPS) is a minimally invasive interventional procedure that consists of placement of an auto expandable metallic stent in the hepatic parenchyma via transjugular. It is used to treat the complications of portal hypertension, particularly digestive bleeding of gullet varices and refractory ascites. Although TIPS is an efficient procedure with low rate of failure some complications such as stenosis are frequent. Early diagnosis of stenosis is mandatory since it interferes with the type of treatment and the reappearing symptoms can be serious. Doppler sonography is used in the follow-up of this patients and many parameters indicating TIPS stenosis are described in the literature such as the minimum and maximum velocity flow inside the stent, the velocity flow in portal vein, the velocity gradient between different sites of the stent, among others. Unfortunately there is no consensus on which parameter or group of parameters is more efficient for diagnosis because the evaluation protocols varied among institutions. The authors reviewed the parameters of stenosis reported in literature and other important aspects for comprehension of this procedure including indications, contraindications and physiopathology of stenosis

Detection and Diagnosis of PVY

International audienceThe worldwide prevalence of Potato virus Y (PVY) poses a continuous challenge to efficient potato production. The accurate diagnosis of viruses such as PVY is inherently challenging due to the broad biological and genetic diversity of PVY strains that elicit a range of symptoms and diseases in various potato cultivars and related solanaceous species. A wide range of techniques have been developed over a period of 50 years for the detection of PVY. Serological methods such as ELISA, using polyclonal and especially monoclonal antibodies, have been widely used by most diagnostic laboratories, due to their cost effectiveness and capacity to implement for a large number of samples. Over the last decade, PCR-based assays have been routinely used in diagnostic laboratories because of their sensitivity, specificity and their capacity to be automated for high-throughput testing. The objective of this chapter is to provide a brief historical overview of the main diag-nostic methods used to detect and identify PVY and to highlight those that are suit-able for either research or diagnostic purposes