55 research outputs found
Distinguishing damages from two earthquakes âArchaeoseismology of a Crusader castle (Al-Marqab citadel, Syria)
Damages from two major earthquakes are identified in medieval Al-Marqab citadel (Latin: Margat) in coastal Syria. Built by the Order of St. John (Hospitallers) in the twelfthâthirteenth centuries, the hilltop fortification has masonry walls made with and without mortar, using the opus caementum technology (Roman concrete). V-shaped and U-shaped failures, single-corner and symmetrical corner collapses, and in-plane shifts of ashlar masonry walls are identified and dated by historical and archaeological methods. The azimuth of displacement is NE-SW for the older
damages of the Crusader period (A.D. 1170â1285), possibly related to the A.D. 1202 earthquake. A later, NW-SE displacement occurred during the Muslim period (post-
1285). The 1202 earthquake produced at least VIII intensity on the MSK scale at Al-Marqab, which is higher than previously considered
KĂ©t földrengĂ©s SzĂriĂĄban â Margat vĂĄrĂĄnak archeoszeizmolĂłgiĂĄja
KĂ©t nagyobb, egymĂĄsra következĆ földrengĂ©s ĂĄltal okozott sĂ©rĂŒlĂ©seket azonosĂtottunk Margat (arabul al-Marqab) keresztes vĂĄrĂĄban, SzĂria tengerparti rĂ©giĂłjĂĄban. A Szent JĂĄnos-lovagrend (johannita lovagok) ĂĄltal a 12â13. szĂĄzadban emelt erĆdĂtmĂ©ny erĆs kĆfalakbĂłl ĂĄll, melyet az opus caementum (rĂłmai beton) technolĂłgiĂĄjĂĄval Ă©pĂtettek. V- Ă©s U-alakĂș falsĂ©rĂŒlĂ©sek, egyoldali Ă©s szimmetrikus sarokomlĂĄsok, valamint a falak megnyĂșlĂĄsa törtĂ©neti Ă©s rĂ©gĂ©szeti mĂłdszerekkel datĂĄlhatĂłak. A keresztes idĆszakra (Kr. u. 1170â1285) datĂĄlt idĆsebb sĂ©rĂŒlĂ©sek ĂK-DNy rezgĂ©s következtĂ©ben keletkeztek, valĂłszĂnƱleg az 1202-es földrengĂ©s következtĂ©ben. Az 1285-ben kezdĆdött muzulmĂĄn uralom idejĂ©n keletkezett sĂ©rĂŒlĂ©sek ĂNy-DK rezgĂ©sirĂĄnyrĂłl tanĂșskodnak. A libanoni Baalbekben kipattant 1202-es földrengĂ©s >VIII MSK intenzitĂĄst eredmĂ©nyezett Margatban; ez magasabb az eddigi feltĂ©telezett Ă©rtĂ©knĂ©l
InformĂĄciĂłs asszimmetria, vĂĄllalti tudĂĄs, piaci szerkezet Ă©s gazdasĂĄgi teljesĂtmĂ©ny Kelet-KözĂ©p EurĂłpĂĄban = Asymmetric information, Corporate, Knowledge, Market Structure and Corporate Performance in Central and Eastern Europe
A kutatĂĄs sorĂĄn azt vizsgĂĄltuk, hogyan befolyĂĄsolja a vĂĄllalatok mƱködĂ©sĂ©t, hatĂ©konysĂĄgĂĄt az a tĂ©ny, hogy többnyire hiĂĄnyos informĂĄciĂłk alapjĂĄn hozzĂĄk meg döntĂ©seiket. Emellett arra a kĂ©rdĂ©sre kerestĂŒk a vĂĄlaszt, hogy mikĂ©ppen hozzĂĄk lĂ©tre maguk a cĂ©gek azokat az informĂĄciĂłkat, amelyek azutĂĄn gazdasĂĄgi környezetĂŒk rĂ©szĂ©vĂ© vĂĄlnak. Ilyen esetekben a vĂĄllalatok ĂĄltal ""termelt"" informĂĄciĂłk a szabĂĄlyozĂĄs rĂ©szĂ©vĂ© vĂĄlnak. Mivel a vĂĄllalatok Ă©s a szabĂĄlyozĂł között aszimmetrikus informĂĄciĂłs helyzet ĂĄll fenn, a szabĂĄlyozĂĄs önmagĂĄban is torzĂthatja a vĂĄllalat döntĂ©si környezetĂ©t Ă©s Ăgy vĂ©geredmĂ©nyben leronthatja a cĂ©gek mƱködĂ©sĂ©t. KutatĂĄsunknak szomorĂș aktualitĂĄst adott az USA-bĂłl kiindult, majd a fejlett Ă©s közepesen fejlett pĂ©nzpiacĂș orszĂĄgokra is ĂĄtterjedt pĂ©nzĂŒgyi Ă©s gazdasĂĄgi vĂĄlsĂĄg (visszaesĂ©s), amely jĂłl mutatja, hogy a gazdasĂĄgi szereplĆk döntĂ©seit milyen mĂ©rtĂ©kben kĂ©pes torzĂtani az informĂĄciĂłk nem megfelelĆ minĆsĂ©ge Ă©s terjedĂ©si mechanizmusa. KutatĂĄsaink fĆ következtetĂ©se az, hogy a MagyarorszĂĄgon, szĂ©lesebb Ă©rtelemben az EU-ban, de a vilĂĄg mĂĄs rĂ©szein is lĂ©tezĆ Ășn. ""költsĂ©g-alapĂș szabĂĄlyozĂĄs"" nem vezet hatĂ©kony gazdasĂĄgi eredmĂ©nyekhez. A megoldĂĄst az Ășn. ""ösztönzĆ szabĂĄlyozĂĄs"" jelentheti, amelynek elmĂ©leti alapjai többĂ©-kevĂ©sbĂ© kidolgozottak, bevezetĂ©se azonban nem tƱnik közelinek. | What impact incomplete and insufficient information on the side of the companies may have on corporate performance. In addition, we analyzed how do firms produce corporate information and knowledge that, in turn, will affect the economic (business) and regulatory environment of the companies themselves. Our research focused on industries where industry regulation complements competition policy. Thus, we analyzed the production and use of information in the telecommunications industry, in postal services and the financial sector. Since firms and the regulator possess incomplete information and they play the game under asymmetric information, regulation itself may distort the economic environment of the firm and it may ultimately result in inefficient corporate outcome. The current financial and economic crisis provides a sad and unpleasant relevance to our research. Our analysis shows how deeply the insufficient quality of information and its distorted propagation mechanism may affect the productivity and efficiency level of corporations. Our main conclusion is that incentive regulation rather than the currently prevalent ""cost-based regulation"" may result in hiher economic and social (Pareto-) efficiency of the companies operation. The theoretical foundations of such a regulatory regime are more or less known but it may take some time until these results can be used in designing practical regulatory tools
Ăj hĂĄromfogĂș kĂ©ntartalmĂș ligandumok szintĂ©zise Ă©s alkalmazĂĄsa rutĂ©nium-katalizĂĄlt hidrogĂ©nezĂ©si reakciĂłkban: New tridentate thioether ligands: synthesis and application in ruthenium-catalyzed hydrogenation reactions
Tridentate ligand containing transition metal complexes are frequently used catalytic systems in industrial scale syntheses due to their high activity and selectivity. In addition to the nature of the metal, the steric and electronic properties of the ligand significantly influence the activity and selectivity of the catalytic system. In our research group, we investigated the coordination and catalytic properties of several ruthenium complexes modified with pentane-2,4-diyl based ligands containing P-, N-, and S-donoratoms. The structure of the [RuII(PNS)(PPh3)Cl2] type compounds were examined in liquid and solid phase as well. By using the novel ruthenium complexes the hydrogenation of unsaturated ketones has been carried out with outstanding chemoselectivity, and it has been proven that the enantioselective hydrogenation of Îł-ketoesters and the subsequent ring-closing reaction of the product could simultaneously be implemented. In this catalytic transformation the enantioselective synthesis of Îł-valerolactone could be realized. The research was supported by the NKFIH K128074, GINOP-2.3.2-15-2016-00008 and GINOP-2.3.3-15-2016-00004 projects.
Kivonat
Nagy hatĂ©konysĂĄguk miatt mĂĄr ipari szintĂ©zisekben is alkalmaznak hĂĄromfogĂș ligandummal mĂłdosĂtott ĂĄtmenetifĂ©m-komplexeket. Ezen katalizĂĄtorokban a központi atom minĆsĂ©ge mellett a ligandum szerkezete, sztĂ©rikus Ă©s elektronikus tulajdonsĂĄgai is jelentĆsen befolyĂĄsoljĂĄk a katalitikus rendszer aktivitĂĄsĂĄt Ă©s szelektivitĂĄsĂĄt. KutatĂłcsoportunkban pentĂĄn-2,4-diil-vĂĄzzal rendelkezĆ P-, N- Ă©s S-donoratomokat tartalmazĂł ligandummal mĂłdosĂtott rutĂ©nium-komplexek koordinĂĄciĂłs Ă©s katalitikus tulajdonsĂĄgait vizsgĂĄltuk. Az elĆĂĄllĂtott [RuII(PNS)(PPh3)Cl2] komplexek szerkezetĂ©t mind oldat, mind szilĂĄrd fĂĄzisban tanulmĂĄnyoztuk. A [RuII(PNS)(PPh3)Cl2] tĂpusĂș komplexek alkalmazĂĄsĂĄval telĂtetlen ketonok hidrogĂ©nezĂ©se kiemelkedĆ kemoszelektivitĂĄssal megy vĂ©gbe, tovĂĄbbĂĄ a Îł-ketoĂ©szterek enantioszelektĂv hidrogĂ©nezĂ©se Ă©s a kĂ©pzĆdĆ termĂ©k gyƱrƱzĂĄrĂĄsa egyidejƱleg kivitelezhetĆ. UtĂłbbi reakciĂłban Îł-valerolakton szintĂ©zisĂ©t enantioszelektĂv körĂŒlmĂ©nyek között sikerĂŒlt kiviteleznĂŒnk. A kutatĂĄs az NKFIH K128074, GINOP-2.3.2-15-2016-00008 Ă©s GINOP-2.3.3-15-2016-00004 projektek keretĂ©ben kerĂŒlt megvalĂłsĂtĂĄsra
Population dynamics and genetic changes of Picea abies in the South Carpathians revealed by pollen and ancient DNA analyses
Background: Studies on allele length polymorphism designate several glacial refugia for Norway spruce (Picea abies) in the South Carpathian Mountains, but infer only limited expansion from these refugia after the last glaciation. To better understand the genetic dynamics of a South Carpathian spruce lineage, we compared ancient DNA from 10,700 and 11,000-year-old spruce pollen and macrofossils retrieved from Holocene lake sediment in the Retezat Mountains with DNA extracted from extant material from the same site. We used eight primer pairs that amplified short and variable regions of the spruce cpDNA. In addition, from the same lake sediment we obtained a 15,000-years-long pollen accumulation rate (PAR) record for spruce that helped us to infer changes in population size at this site. Results: We obtained successful amplifications for Norway spruce from 17 out of 462 pollen grains tested, while the macrofossil material provided 22 DNA sequences. Two fossil sequences were found to be unique to the ancient material. Population genetic statistics showed higher genetic diversity in the ancient individuals compared to the extant ones. Similarly, statistically significant Ks and Kst values showed a considerable level of differentiation between extant and ancient populations at the same loci. Lateglacial and Holocene PAR values suggested that population size of the ancient population was small, in the range of 1/10 or 1/5 of the extant population. PAR analysis also detected two periods of rapid population growths (from ca. 11,100 and 3900 calibrated years before present (cal yr BP)) and three bottlenecks (around 9180, 7200 and 2200 cal yr BP), likely triggered by climatic change and human impact. Conclusion: Our results suggest that the paternal lineages observed today in the Retezat Mountains persisted at this site at least since the early Holocene. Combination of the results from the genetic and the PAR analyses furthermore suggests that the higher level of genetic variation found in the ancient populations and the loss of ancient allele types detected in the extant individuals were likely due to the repeated bottlenecks during the Holocene. This study demonstrates how past population size changes inferred from PAR records can be efficiently used in combination with ancient DNA studies. The joint application of palaeoecological and population genetic analyses proved to be a powerful tool to understand the influence of past population demographic changes on the haplotype diversity and genetic composition of forest tree species
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