DEVELOPMENT OF PISTON SEALS FOR DEEP OIL-WELL PROBES FOR HIGH PRESSURE AND TEMPERATURE MEDIUM

In this paper the results of a finalized phase of the present test programme are published. It is considered only a stage (of the research work on dynamic seals for oil well probe application) when reasonable solutions were found. The results obtained are promising and already provide satisfactory solution for industrial problems. Compared to the requirements, the endurance test results proved much longer life at an acceptable friction loss. During the possible next phases of the test programmes more design alternatives, seal materials, friction surface materials and qualities should be subjected to endurance test in order to select the most suitable alternatives of the seals and also to optimize them. (Where optimizing the seals means: to obtain, or develop, the most reliable alternatives which produce the possible longest life, belonging to leak proof operation, and smallest friction loss at the operation parameters.) Friction characteristics tests should be carried out too for the selected design alternatives to obtain the required design aids for proper estimation of the expected friction forces at different working parameters

DEVELOPMENT OF PISTON SEALS FOR DEEP OIL-WELL PROBES FOR HIGH PRESSURE AND TEMPERATURE MEDIUM

In this paper the results of a finalized phase of the present test programme are published. It is considered only a stage (of the research work on dynamic seals for oil well probe application) when reasonable solutions were found. The results obtained are promising and already provide satisfactory solution for industrial problems. Compared to the requirements, the endurance test results proved much longer life at an acceptable friction loss. During the possible next phases of the test programmes more design alternatives, seal materials, friction surface materials and qualities should be subjected to endurance test in order to select the most suitable alternatives of the seals and also to optimize them. (Where optimizing the seals means: to obtain, or develop, the most reliable alternatives which produce the possible longest life, belonging to leak proof operation, and smallest friction loss at the operation parameters.) Friction characteristics tests should be carried out too for the selected design alternatives to obtain the required design aids for proper estimation of the expected friction forces at different working parameters

Granulometric characterization of paleosols in loess series by automated static image analysis

An automated image analysis method is proposed here to study the size and shape of siliciclastic sedimentary particles of paleosols of Central European loess sequences. Several direct and indirect measurement techniques are available for grain size measurements of sedimentary mineral particles. Indirect techniques involve the use of some kind of physical laws, however, all requirements for calculations are in many cases not known. Even so, the direct manual microscopic observation and measurement of large, representative number of grains is time-consuming and sometimes rather subjective. Therefore, automated image analyses techniques provide a new and perspective way to analyse grain size and shape sedimentary particles. Here we test these indirect (laser diffraction) and direct (automated static image analysis) techniques and provide new granulometric (size and shape) data of paleosols. Our results demonstrate that grain size data of the mineral dust samples are strongly dependent on shape parameters of particles, and shape heterogeneity was different between different size classes. Due to the irregular grain shape parameters, uncertainties have arisen also for determination of grain sizes. In this paper we present a possible correction procedure to reduce the differences among the results of the laser diffraction and image analysis methods. By applying new correction factors, results of the two approaches could become closer but the unknown thickness of particles remains a problem to solve. The other presented correction procedure to assess the uncertain 3rd dimension of particles by their intensity-size relationships makes us able to reduce further the deviations of the two sizing methods

Nesting activity of cavity-nesting bees and wasps is lower in small-scale apple orchards compared to nearby semi-natural habitats

Commercially reared cavity-nesting bees have been studied mainly in large, intensively managed orchards. However, knowledge on wild cavity-nesting bee and wasp communities and their potential limitations in smaller orchards remain insufficient. We compared the colonization rate of trapnests, nesting success, parasitism and response to flower resources of cavity-nesting bees and wasps between apple orchards and nearby semi-natural habitats (SNHs). Trapnests were placed in orchards and neighbouring SNHs. Colonization dynamics were studied and herbaceous flower resources were estimated. Furthermore, nest and brood cell quantity, number of alive offspring and nest parasitism rate were assessed. We found a higher colonization rate in the SNHs than in the orchards. Both bees and wasps made more nests, completed more brood cells and had a higher number of alive offspring in the SNHs. The number of bee nests in the orchards showed a positive correlation with the species richness of the flowering plants. The nest parasitism of wasps was higher in the SNHs. Apple orchards in the studied small-scale system were generally less colonized by cavity-nesting hymenopterans than nearby SNHs that can be important reservoirs of these ecosystem service provider hymenopterans. Our results highlight the importance of diverse flowering herbaceous vegetation in the understory that increased the number of bee nests in orchards and that could have a positive effect on the nesting activity of the bee species active in summer. Therefore, management practices that support flowering plant species in the understory vegetation are highly recommended in such orchards

A fogászati paradigmaváltás következményei

A paradigma főnév az 1960-as évektől fordul elő gyakrabban tudományos közleményekben. A változás a meglévő vélemény, az ismeretek, a felfedezések, az új tapasztalatok, a technológia és tudásalapok révén szükségessé teszi az eddigi viszonyítási rendszerek és referenciaalapok átgondolását, és új paradigma elfogadását. A gyógyításban erre akkor kerül sor, ha a fennálló nézetek már nem használhatóak az újabb felfedezések, a fejlődés, az új ismeretek tükrében. A 90-es években a magyarországi rendszerváltás paradigmaváltásával a fogászati ellátás is változott. A tulajdonviszonyok, gazdasági, finanszírozási normák változása a 2020-as évi járvány a fej-nyaki maxillo-faciális- és szájsebészeti ellátás eddigi paradigmáit is a gazdasági, politikai váltást követően gyökeresen megváltoztatta

Disease course, frequency of relapses and survival of 73 patients with juvenile or adult dermatomyositis

Objective Our aim is to present the disease course, frequency of relapses and survival of juvenile and adult dermatomyositis (JDM/DM) patients. Methods Analysis was performed using data on 73 patients. The median follow-up for 38 JDM patients was 32 months and 78 months for 35 adult DM patients. Results 23/38 JDM patients (60%) had monophasic, 12/38 (31.6%) had polycyclic and 3138 (7.9%) had chronic disease. Among children treated only with glucocorticoids, 12/20 (60%) had monophasic and 8/20 (40%) had polycyclic disease. 10/17 (58.8%) children, who required second-line immunosuppressive agents, had monophasic and 4/17 (23.5%) had polycyclic disease. 18/35 DM (51.4%) patients had monophasic, 13/35 (37.1%) had polycyclic, 1/35 (2.9%) had chronic disease and 3135 (8.6%) had fulminant myositis. Among DM patients requiring only glucocorticoids, 12/20 (60%) were monophasic and 8/20 (40%) were polycyclic. In patients requiring second-line immunosuppressive agents, 6/15 patients (40%) had monophasic and 5/15 (33.3%) had polycyclic disease. Among patients with polycyclic disease, the risk of relapse was higher during first year than later in the disease course. None of the JDM patients have died, while 4 disease-specific deaths occurred in adult patients. There was no significant difference between the survival of JDM and DM patients. Discussion There was no correlation between relapse-free survival and the initial therapeutic regimen. Many of our patients had polycyclic or chronic disease. As relapses can occur after a prolonged disease-free interval, patients should be followed for at least 2 years. Although we found a favourable survival rate, further investigations are needed to assess functional outcome

Saharan dust deposition in the Carpathian Basin and its possible effects on interglacial soil formation.

Several hundred tons of windblown dust material are lifted into the atmosphere and are transported every year from Saharan dust source areas towards Europe having an important climatic and other environmental effect also on distant areas. According to the systematic observations of modern Saharan dust events, it can be stated that dust deflated from North African source areas is a significant constituent of the atmosphere of the Carpathian Basin and Saharan dust deposition events are identifiable several times in a year. Dust episodes are connected to distinct meteorological situations, which are also the determining factors of the different kinds of depositional mechanisms. By using the adjusted values of dust deposition simulations of numerical models, the annual Saharan dust flux can be set into the range of 3.2–5.4 g/m2/y. Based on the results of past mass accumulation rates calculated from stratigraphic and sedimentary data of loess–paleosol sequences, the relative contribution of Saharan dust to interglacial paleosol material was quantified. According to these calculations, North African exotic dust material can represent 20–30% of clay and fine silt-sized soil components of interglacial paleosols in the Carpathian Basin. The syngenetic contribution of external aeolian dust material is capable to modify physicochemical properties of soils and hereby the paleoclimatic interpretation of these pedogene stratigraphic units

The effects of putrescine are partly overlapping with osmotic stress processes in wheat

Polyamine metabolism is in relation with several metabolic pathways and linked with plant hormones or signalling molecules; in addition polyamines may modulate the up- or down-regulation of gene expression. However the precise mechanism by which polyamines act at the transcription level is still unclear. In the present study the modifying effect of putrescine pre-treatment has been investigated using the microarray transcriptome profile analysis under the conditions where exogenous putrescine alleviated osmotic stress in wheat plants. Pre-treatment with putrescine induced the unique expression of various general stress-related genes. Although there were obvious differences between the effects of putrescine and polyethylene glycol treatments, there was also a remarkable overlap between the effects of putrescine and osmotic stress responses in wheat plants, suggesting that putrescine has already induced defence processes under control conditions. The fatty acid composition in certain lipid fractions and the antioxidant enzyme activities have also been specifically changed under osmotic stress conditions or after treatment with putrescine