Logical Linked Data Compression

Linked data has experienced accelerated growth in recent years. With the continuing proliferation of structured data, demand for RDF compression is becoming increasingly important. In this study, we introduce a novel lossless compression technique for RDF datasets, called Rule Based Compression (RB Compression) that compresses datasets by generating a set of new logical rules from the dataset and removing triples that can be inferred from these rules. Unlike other compression techniques, our approach not only takes advantage of syntactic verbosity and data redundancy but also utilizes semantic associations present in the RDF graph. Depending on the nature of the dataset, our system is able to prune more than 50% of the original triples without affecting data integrity

Ferrimagnetism and disorder in epitaxial Mn(2-x)Co(x)VAl thin films

The quaternary full Heusler compound Mn(2-x)Co(x)VAl with x = 1 is predicted to be a half-metallic antiferromagnet. Thin films of the quaternary compounds with x = 0...2 were prepared by DC and RF magnetron co-sputtering on heated MgO (001) substrates. The magnetic structure was examined by x-ray magnetic circular dichroism and the chemical disorder was characterized by x-ray diffraction. Ferrimagnetic coupling of V to Mn was observed for Mn2VAl (x = 0). For x = 0.5, we also found ferrimagnetic order with V and Co antiparallel to Mn. The observed reduced magnetic moments are interpreted with the help of band structure calculations in the coherent potential approximation. Mn2VAl is very sensitive to disorder involving Mn, because nearest-neighbor Mn atoms couple anti-ferromagnetically. Co2VAl has B2 order and has reduced magnetization. In the cases with x >= 0.9 conventional ferromagnetism was observed, closely related to the atomic disorder in these compounds.Comment: 10 pages, 4 figure

The Origins of Lactase Persistence in Europe

Lactase persistence (LP) is common among people of European ancestry, but with the exception of some African, Middle Eastern and southern Asian groups, is rare or absent elsewhere in the world. Lactase gene haplotype conservation around a polymorphism strongly associated with LP in Europeans (−13,910 C/T) indicates that the derived allele is recent in origin and has been subject to strong positive selection. Furthermore, ancient DNA work has shown that the −13,910*T (derived) allele was very rare or absent in early Neolithic central Europeans. It is unlikely that LP would provide a selective advantage without a supply of fresh milk, and this has lead to a gene-culture coevolutionary model where lactase persistence is only favoured in cultures practicing dairying, and dairying is more favoured in lactase persistent populations. We have developed a flexible demic computer simulation model to explore the spread of lactase persistence, dairying, other subsistence practices and unlinked genetic markers in Europe and western Asia's geographic space. Using data on −13,910*T allele frequency and farming arrival dates across Europe, and approximate Bayesian computation to estimate parameters of interest, we infer that the −13,910*T allele first underwent selection among dairying farmers around 7,500 years ago in a region between the central Balkans and central Europe, possibly in association with the dissemination of the Neolithic Linearbandkeramik culture over Central Europe. Furthermore, our results suggest that natural selection favouring a lactase persistence allele was not higher in northern latitudes through an increased requirement for dietary vitamin D. Our results provide a coherent and spatially explicit picture of the coevolution of lactase persistence and dairying in Europe

Crohn's colitis perforation due to superimposed invasive amebic colitis: A case report

PubMed ID: 16830298The clinical and microscopic appearances of inflammatory bowel disease may be very similar to those of amebic colitis. The coexistence of invasive amebiasis with inflammatory bowel disease may have disastrous results. Patients with inflammatory bowel disease have a greater prevalence of amebiasis, but this association is more significant for ulcerative colitis. There have been very few reports in the literature presenting the superimposition of amebiasis on Crohn's disease. In this report, a rare case of Crohn's colitis with superimposed amebiasis resulting in colonic perforation is presented. Patients with inflammatory bowel disease traveling to endemic areas may benefit from receiving a course of prophylactic anti-amebic medication

Contents of trace elements and sulphur in the leaves of deciduous trees along the roads of Zonguldak, Turkey

In this study, 16 trace elements (Al, B, Ba, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Ni, Pb, Sr, V, Zn) and S were found in unwashed leaves of several deciduous tree species [Alnus glutinosa (L.) Gaertner, Platanus orientalis L., Salix babylonica L.]. Samples were collected from 28 points distributed over 5 sites representing different traffic intensities in the city of Zonguldak. The relationships of sampling sites were determined using the UPGMA method. According to the results of analyses, the trace element and S concentrations in the observed tree species were ordered as follows: S>Mg>Fe>Sr>Zn> B>Ba>Al>Mn>Cu>Pb> Ni> V>Cr>Li>Co>Cd in Alnus glutinosa; S>Mg>Fe>Sr>Zn> Mn> Ba >Al>B>Cu>Pb> Cr>V>Li>Ni>Co>Cd in Platanus orientalis; S>Fe>Mg>Zn> Sr>Al>Ba>B>Mn>Cu> V>Pb>Ni>Li>Cr>Cd>Co in Salix babylonica. Significant positive correlations existed between the amount of heavy metals (r=0.81-1.00). The results are discussed in the context of prior studies. © by PSP

Fission track dating obsidians in Central and Northern Anatolia

Twenty obsidian samples from Central and North Anatolia were dated by the fission track method. Split samples analyzed in two different laboratories give consistent results. Data presented refer to three volcanic fields and are summarized as follows: Orta-Sakaeli (Northern Anatolia) obsidians with ages from 21-23 Ma; Göllü Dagi dome complex near Çiftlik (Central anatolia) has given ages between 1.33-0.98 Ma; Acigöl caldera (Central Anatolia) shows three age groups: (1) Eruptions of precaldera (Bogazköy) obsidians with ages 0.18-0.15 Ma; (2) Formation of the large intracaldera dome Kocadag-Taskesiktepe at about 0.08 Ma (uncorrected "apparent" age of 0.075 Ma); and (3) Acigöl peripheral obsidian domes with plateau ages of 0.020 and 0.019 Ma, and an additional uncorrected age of 0.018 Ma form a distinct age group. This fission track parameters discriminate between the various obsidian sources of prehistoric obsidian artifacts. © 1993 Springer-Verlag

Application of fission track dating to archaeometry: Provenance studies of prehistoric obsidian artifacts

Several obsidian artifacts from Anatolian (Turkey) Neolithic sites have been analysed by the FT dating method and the results have been compared with data referring to obsidian natural sources located in the Mediterranean and adjacent regions. The conclusions can be summarized as follows: (1) some of the artifacts are very probably from Central Anatolian sources, others from Northern Anatolian sources, (2) the remaining artifacts are from unidentified sources, probably located or in Eastern Anatolia or in Western Anatolia and (3) the Carpathian and Aegean sources are not represented in the studied sample set. Comparison between the FT dating method and the trace elements composition by Instrumental Neutron Activation Analysis (INAA) shows that the combination of these two approaches is a powerful tool for provenance studies of prehistoric obsidian artifacts. © 1994.Consiglio Nazionale delle RicercheThis work has been carried out as a part of a joint research project, and was financially supported by CNR (Italy) sad TuBrrAK (Turkey). We wish to thank CNR and TUBITAK