Társadalmi különbségek a Magyar Királyság központi területeinek 10–14. századi falusias településein = Social differences within 10th–14th centuries rural settlement types in the central area of the Hungarian Kingdom

Present paper analyses some aspects of hierarchy within 10th–14th centuries villages, farms and intermediate forms of habitation using mainly the data of excavations and field surveys in Pest County

Optimization of activator solution and heat treatment of ground lignite type fly ash geopolymers

Geopolymers are inorganic polymers which can be produced by the reaction between silico aluminate oxides and alkali silicates in alkaline medium. Materials containing silica and alumina compounds are suitable for geopolymer production. These can be primary materials or industrial wastes, i. e. fly ash, metallurgical slag and red mud. In this paper, the results of the systematic experimental series are presented which were carried out in order to optimize the geopolymer preparation process. Fly ash was ground for different residence time (0, 5, 10, 30, 60 min) in order to investigate the optimal specific surface area. NaOH activator solution concentration also varied (6, 8, 10, 12, 14 M). Furthermore, sodium silicate was added to NaOH as a network builder solution. In this last serie different heat curing temperatures (30, 60, 90°C) were also applied. After seven days of ageing the physical properties of the geopolymer(compressive strength and specimen density)were measured. Chemical leaching tests on the rawmaterial and the geopolymers were carried out to determine the elements which can be mobilized by different leaching solutions. It was found that the above mentioned parameters (fly ash fineness, molar concentration and composition of activator solution, heat curing) has great effect on the physical and chemical properties of geopolymer specimens. Optimal conditions were as follows: specific surface area of the fly ash above 2000 cm2/g, 10 M NaOH, 30o C heat curing temperature which resulted in 21 MPa compressive strength geopolymer

Importance of bicarbonate transport in pH control during amelogenesis - need for functional studies.

Dental enamel, the hardest mammalian tissue, is produced by ameloblasts. Ameloblasts show many similarities to other transporting epithelia although their secretory product, the enamel matrix, is quite different. Ameloblasts direct the formation of hydroxyapatite crystals, which liberate large quantities of protons that then need to be buffered to allow mineralization to proceed. Buffering requires a tight pH regulation and secretion of bicarbonate by ameloblasts. Many investigations have used immunohistochemical and knockout studies to determine the effects of these genes on enamel formation, but up till recently very little functional data were available for mineral ion transport. To address this, we developed a novel 2D in vitro model using HAT-7 ameloblast cells. HAT-7 cells can be polarized and develop functional tight junctions. Furthermore, they are able to accumulate bicarbonate ions from the basolateral to the apical fluid spaces. We propose that in the future, the HAT-7 2D system along with similar cellular models will be useful to functionally model ion transport processes during amelogenesis. Additionally, we also suggest that similar approaches will allow a better understanding of the regulation of the cycling process in maturation-stage ameloblasts, and the pH sensory mechanisms, which are required to develop sound, healthy enamel

Alkalmazkodási stratégiák a vidék gazdaságában = Adaptational strategies in rural economy

A hároméves, különböző jellegű vidéki települések alkalmazkodási stratégiáinak feltérképezésére irányuló kutatásunk négy megyében zajlott: dolgoztunk munkanélküliség által erősen sújtott, perifériális helyzetben lévő mezőgazdasági-, valamint volt-ipari térségben, továbbá nagyvárosok vonzáskörzetében jobb helyzetben levő mezőgazdasági és vállalkozó faluban is. Négy településen (Szatmárcseke, Borsodnádasd, Derecske és Tarján) mélyfúrás jellegű kutatás zajlott; nagyszámban készültek interjúk, Borsodnádasdon és Szatmárcsekén egyetemi diákok segítségével kérdőíves felmérés is zajlott. Mikrotérségi szintű vizsgálat folyt Derecske környékén (5 település) és a szatmári Tiszaháton (13 település). Az OTKA kutatás keretében összesen 858 kérdőív, 180 db. interjú készült, ami mellett térségi és helyi statisztikákat, és egyéb forrásokat is gyűjtöttünk. Emellett az Alapítvány 2007-ben Kétvölgyön a résztvevőkutatók számára műhelyvitát rendezett, majd a Magyar Művelődési Intézettel közösen decemberben konferenciát szervezett "Fiatal kutatók Márkus István nyomdokain: falukutatók Borsodnádasdon" címmel, amin a kutatók mellett a Debreceni Egyetem és az ELTE is képviseltették magát. A három év alatt az öt kutató 22 konferencia előadást tartott a témában, 8 tanulmányt publikált, további 4 a jelenleg Borsodnádasdról készülő kötetben jelenik meg 2008-ban. A résztvevő kutatók mindegyike doktorjelölt, és dolgozatához felhasználja az OTKA kutatás eredményeit. | The three years long research was executed in four counties: we have worked in peripheral agricultural and collapsed industrial villages, which were distressed very much by unemployment. Besides we have done research also in agricultural and 'entrepreneur' areas near to bigger cities, which are in better situation. There were deep research and many interviews were made in four settlements (Szatmárcseke, Borsodnádasd, Derecske, Tarján); in Borsodnádasd and Szatmárcseke there were quantitative surveys too which were carried out with university students. In five settlements (around Derecske) and in the Szatmár Tiszahát (10 villages) there were micro-regional researches. During the OTKA project we have made 858 questionnaires and 210 interviews, besides regional and local statistics and other information were collected. In 2007 the Foundation organized a workshop for the participant researchers in Kétvölgy and in December with the Hungarian Culture Institute organized a conference with the title of "Young researchers in the wake of Márkus István: researchers in Borsodnádasd" when out of the researchers the Debrecen University and ELTE were also represented themselves. During the three years the five participant researchers had 22 presentations on the subject, 8 studies were published and 4 are under edition in a book of Borsodnádasd. Being the participant researchers Ph.D candidates, writing their thesis they will use the OTKA results