Algebrai struktúrák és algoritmusok = Algebraic structures and algorithms

A pályázat keretében három témakörben --- általános algebra, félcsoportelmélet és döntési problémák bonyolultsága --- nyertünk eredményeket. A kutatás jelentős része hazai, illetve külföldi kutatókkal való együttműködésben született. Bebizonyítottuk, hogy algebrák egy igen tág osztályában azokat a véges algebrákat, amelyek reziduálisan kicsi varietást generálnak, meghatározzák a c-változós kompatibilis relációi, ahol c csak az osztály egy paraméterétől és az alaphalmaz nagyságától függő konstans. Meghatároztuk a legfeljebb 4 többségi függvényt tartalmazó minimális klónokat, valamint azokat a minimális klónt generáló kétváltozós műveleteket, amelyek "majdnem asszociatívak". Általánosítottuk kvázivarietásokra Willard véges azonosságbázis tételét, és egy speciális esetben bebizonyítottuk Pigozzi relatív kongruenciamoduláris kvázivarietásokra vonatkozó véges azonosságbázis sejtését. Jellemeztük a kötegek csoportokkal vett szemidirekt szorzatainak idempotens-szétválasztó homomorf képeit, és ezek reguláris részfélcsoportjait. Bebizonyítottuk, hogy minden E-tömör lokálisan inverz félcsoport beágyazható teljesen egyszerű félcsoport inverz félcsoporttal vett lambda-szemidirekt szorzatába. Algebrai és kombinatorikai jellegű feltételeket adtunk arra, hogy egy lokálisan véges varietás típushalmaza nem tartalmaz 1-es típust, illetve 1-es és 2-es típust. Dichotómiatételt bizonyítottunk polinom-egyenletrendszerek megoldhatóságára olyan algebrák felett, melyek "kizárják" az 1-es típust. | The results of the project belong to three areas: universal algebra, semigroup theory and complexity theory. Most of the research was carried out in international cooperation. We proved that in a wide class of algebras, the finite algebras that generate residually small varieties are determined by their c-ary compatible relations where c is a constant that depends only on a parameter of the class and on the size of the underlying set. We described the minimal clones with at most 4 majority operations, and those binary operations generating a minimal clone which are "almost associative". We generalized the finite basis theorem of Willard to quasivarieties, and proved a conjecture of Pigozzi regarding the finite axiomatizability of relative congruence-modular quasivarieties in a special case. We characterized the idempotent separating homomorphic images of semidirect products of bands by groups, and their regular subsemigroups. We proved that each E-solid locally inverse semigroup is embeddable in a lambda-semidirect product of a completely simple semigroup by an inverse semigroup. We gave algebraic and combinatorial characterizations of the locally finite varieties omitting type 1 and of those omitting types 1 and 2. We proved a dichotomy theorem for the solvability problem of systems of polynomial equations over certain finite algebras

Compared efficacy of preservation solutions on the outcome of liver transplantation: Meta-analysis

AIM: To compare the effects of the four most commonly used preservation solutions on the outcome of liver transplantations. METHODS: A systematic literature search was performed using MEDLINE, Scopus, EMBASE and the Cochrane Library databases up to January 31(st), 2017. The inclusion criteria were comparative, randomized controlled trials (RCTs) for deceased donor liver (DDL) allografts with adult and pediatric donors using the gold standard University of Wisconsin (UW) solution or histidine-tryptophan-ketoglutarate (HTK), Celsior (CS) and Institut Georges Lopez (IGL-1) solutions. Fifteen RCTs (1830 livers) were included; the primary outcomes were primary non-function (PNF) and one-year post-transplant graft survival (OGS-1). RESULTS: All trials were homogenous with respect to donor and recipient characteristics. There was no statistical difference in the incidence of PNF with the use of UW, HTK, CS and IGL-1 (RR = 0.02, 95%CI: 0.01-0.03, P = 0.356). Comparing OGS-1 also failed to reveal any difference between UW, HTK, CS and IGL-1 (RR = 0.80, 95%CI: 0.80-0.80, P = 0.369). Two trials demonstrated higher PNF levels for UW in comparison with the HTK group, and individual studies described higher rates of biliary complications where HTK and CS were used compared to the UW and IGL-1 solutions. However, the meta-analysis of the data did not prove a statistically significant difference: the UW, CS, HTK and IGL-1 solutions were associated with nearly equivalent outcomes. CONCLUSION: Alternative solutions for UW yield the same degree of safety and effectiveness for the preservation of DDLs, but further well-designed clinical trials are warranted

Palaeoenvironmental reconstruction of the Sarmatian (Middle Miocene) Central Paratethys based on palaeontological and geochernical analyses of foraminifera, ostracods, gastropods and rodents

International audiencePaleoenvironmental changes in the upper Middle Miocene Central Parathetys were reconstructed by using qualitative and quantitative palaeontological analyses of foraminifera and ostracods, coupled with trace elemental (Mg/Ca) and stable isotope (delta(18)O and delta(13)C) analyses of their carbonate skeletons and of gastropod sheets. Mean annual air temperatures were estimated using the oxygen isotope composition of contemporaneous rodent teeth. The studied aquatic fossils come from two boreholes in the Zsambek basin (northern central Hungary), while the terrestrial ones are from localities in NE Hungary and E Romania. In the studied Sarmatian successions, three zones could be distinguished, based on palaeontological and geochemical results. At the Badenian/Sarmatian boundary, faunal diversity decreased markedly. In the lower zone a transgressive event culminated in a seawater incursion into the semi-open basin system of the Central Paratheys. Stable bottom-water temperature (similar to 15 degrees C) and variable salinites (20-22\%) are estimated for the Early Sarmatian Sea. The faunal changes (notably a strong reduction in biodiversity) occuring at the boundary between the lower and the middle zone can be explained by a sea-leval highstand with dysoxic conditions. A relative sea-level fall is documented at the end of this middle zone. After a short regressive event, a marine connection between the Paratethys and Mediterranean was established at the beginning of the upper zone. This is indicated by an increased microfaunal diversity and the re-appearance of marine Bademan ostracods and foraminifera, which are completely absent from the older Samatian series. During the upper zone, the temperatures and salmities are estimated to have fluctuated from 15 degrees C to 21 degrees C and from 15 parts per thousand to 43 parts per thousand, respectively

The Nineteenth-Century World of Turkic Dictionaries: An Overview

The author creates a bibliographic picture of the various Turkic-language dictionaries from the eleventh to the end of the nineteenth centuries, in various languages, and describes their structure. He then focuses specifically on printed Turkic dictionaries of the nineteenth century, discussing their historical context and a statistical survey that he conducted. A number of these dictionaries have been digitized; he examines some sites where they are accessible. In the appendix is a list of the dictionaries that he found in the course of his research

Validation of distinct pathogenic patterns in a cohort of membranoproliferative glomerulonephritis patients by cluster analysis

Background: A novel data-driven cluster analysis identified distinct pathogenic patterns in C3-glomerulopathies and immune complex-mediated membranoproliferative glomerulonephritis. Our aim was to replicate these observations in an independent cohort and elucidate disease pathophysiology with detailed analysis of functional complement markers. ----- Methods: A total of 92 patients with clinical, histological, complement and genetic data were involved in the study, and hierarchical cluster analysis was done by Ward method, where four clusters were generated. ----- Results: High levels of sC5b-9 (soluble membrane attack complex), low serum C3 levels and young age at onset (13 years) were characteristic for Cluster 1 with a high prevalence of likely pathogenic variations (LPVs) and C3 nephritic factor, whereas for Cluster 2-which is not reliable because of the small number of cases-strong immunoglobulin G staining, low C3 levels and high prevalence of nephritic syndrome at disease onset were observed. Low plasma sC5b-9 levels, decreased C3 levels and high prevalence of LPV and sclerotic glomeruli were present in Cluster 3, and patients with late onset of the disease (median: 39.5 years) and near-normal C3 levels in Cluster 4. A significant difference was observed in the incidence of end-stage renal disease during follow-up between the different clusters. Patients in Clusters 3-4 had worse renal survival than patients in Clusters 1-2. ----- Conclusions: Our results confirm the main findings of the original cluster analysis and indicate that the observed, distinct pathogenic patterns are replicated in our cohort. Further investigations are necessary to analyse the distinct biological and pathogenic processes in these patient groups

Climate, host and geography shape insect and fungal communities of trees.

Non-native pests, climate change, and their interactions are likely to alter relationships between trees and tree-associated organisms with consequences for forest health. To understand and predict such changes, factors structuring tree-associated communities need to be determined. Here, we analysed the data consisting of records of insects and fungi collected from dormant twigs from 155 tree species at 51 botanical gardens or arboreta in 32 countries. Generalized dissimilarity models revealed similar relative importance of studied climatic, host-related and geographic factors on differences in tree-associated communities. Mean annual temperature, phylogenetic distance between hosts and geographic distance between locations were the major drivers of dissimilarities. The increasing importance of high temperatures on differences in studied communities indicate that climate change could affect tree-associated organisms directly and indirectly through host range shifts. Insect and fungal communities were more similar between closely related vs. distant hosts suggesting that host range shifts may facilitate the emergence of new pests. Moreover, dissimilarities among tree-associated communities increased with geographic distance indicating that human-mediated transport may serve as a pathway of the introductions of new pests. The results of this study highlight the need to limit the establishment of tree pests and increase the resilience of forest ecosystems to changes in climate

C4 nephritic factor in patients with immune-complex-mediated membranoproliferative glomerulonephritis and C3-glomerulopathy

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