54 research outputs found

    Taxonomic revision of the Oligocene percoid fish Oligoserranoides budensis (Heckel, 1856), from the Paratethys and paleobiogeographic comments

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    Small perch-like fishes from the Oligocene of the Paratethys have been traditionally assigned to Serranus budensis (Heckel, 1856). A morphological revision of the holotype and specimens previously assigned to S. budensis from the Outer Carpathians, Poland, is provided herein. They are re-assigned to the species Oligoserranoides budensis (Heckel, 1856) — Percoidei incertae sedis. New specimens assigned to Ol. budensis from the Outer Carpathians, Poland, are introduced. Our results reveal that Ol. budensis is very similar to the species Caucasoserranoides morozkiensis, Carpathoserranoides brnoensis, Carpathoserranoides polonicus and Oligoserranoides comparabilis, and further studies are necessary to revise the validity of those species. Ol. budensis shares many characters with genera Lutjanus and Ocyurus of the superfamily Lutjanoidea. Ol. budensis differs from Lutjanoidea in having a toothless palatine. The palaeobiogeography of Oligocene small perch-like fishes in the Paratethys is presented and discussed

    Taxonomic revision of the Oligocene percoid fish Oligoserranoides budensis (Heckel, 1856), from the Paratethys and paleobiogeographic comments

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    Small perch-like fishes from the Oligocene of the Paratethys were traditionally assigned to Serranus budensis (Heckel, 1856). A new morphological study of the holotype and specimens from the Outer Carpathians, Poland, is provided herein. Oligoserranoides budensis (Heckel, 1856), Percoidei incertae sedis, is revised and compared with other small perch-like fishes from the Oligocene Paratethys. Caucasoserranoides morozkiensis, Carpathoserranoides brnoensis, Carpathoserranoides polonicus and Oligoserranoides comparabilis are very similar to O. budensis and further studies are necessary to clarify the validity of those species. O. budensis is compared with the Oligocene-Lower Miocene Pirsagatia sytchevskayae, the Eocene Jimtylerius temnopterus, Ottaviania mariae,O. leptacanthus, Veranichthys ventralis and the Palaeocene Proserranus lundensis. O. budensis shares many characters with the Lutjanoidea, and differs in a toothless palatine. The palaeobiogeography of Oligocene small perch-like fishes in the Paratethys is presented

    Chiral doublers of heavy-light baryons

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    We discuss the consequences of the chiral doubling scenario for baryons built of heavy and light quarks. In particular, we use the soliton description for baryons, demonstrating why each heavy-light baryon should be accompanied by the opposite parity partner. Our argumentation holds both for ordinary baryons and for exotic heavy pentaquarks which are required by the symmetries of QCD to appear in parity doublets, seperated by the mass shift of the chiral origin. Interpreting the recently observed by BaBaR, CLEO and Belle charmed mesons with assignment (0+,1+)(0^+,1^+) as the chiral partners of known DD and DD^* mesons, allows us to estimate the parameters of the mesonic effective lagrangian, and in consequence, estimate the masses of ground states and excited states of both parities. In particular, we interpret the state recently reported by the H1 experiment at HERA as a chiral partner Θ~c0(3099)\tilde{\Theta}_c^0(3099) of yet undiscovered ground state pentaquark Θc0(2700)\Theta_c^0(2700).Comment: 10 pages, in v2 some typos corrected, references adde

    Human MC4R variants affect endocytosis, trafficking and dimerization revealing multiple cellular mechanisms involved in weight regulation.

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    The Melanocortin-4 Receptor (MC4R) plays a pivotal role in energy homeostasis. We used human MC4R mutations associated with an increased or decreased risk of obesity to dissect mechanisms that regulate MC4R function. Most obesity-associated mutations impair trafficking to the plasma membrane (PM), whereas obesity-protecting mutations either accelerate recycling to the PM or decrease internalization, resulting in enhanced signaling. MC4R mutations that do not affect canonical Gαs protein-mediated signaling, previously considered to be non-pathogenic, nonetheless disrupt agonist-induced internalization, β-arrestin recruitment, and/or coupling to Gαs, establishing their causal role in severe obesity. Structural mapping reveals ligand-accessible sites by which MC4R couples to effectors and residues involved in the homodimerization of MC4R, which is disrupted by multiple obesity-associated mutations. Human genetic studies reveal that endocytosis, intracellular trafficking, and homodimerization regulate MC4R function to a level that is physiologically relevant, supporting the development of chaperones, agonists, and allosteric modulators of MC4R for weight loss therapy

    Measurement of global polarization of {\Lambda} hyperons in few-GeV heavy-ion collisions

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    The global polarization of {\Lambda} hyperons along the total orbital angular momentum of a relativistic heavy-ion collision is presented based on the high statistics data samples collected in Au+Au collisions at \sqrt{s_{NN}} = 2.4 GeV and Ag+Ag at 2.55 GeV with the High-Acceptance Di-Electron Spectrometer (HADES) at GSI, Darmstadt. This is the first measurement below the strangeness production threshold in nucleon-nucleon collisions. Results are reported as a function of the collision centrality as well as a function of the hyperon transverse momentum (p_T) and rapidity (y_{CM}) for the range of centrality 0--40%. We observe a strong centrality dependence of the polarization with an increasing signal towards peripheral collisions. For mid-central (20--40%) collisions the polarization magnitudes are (%) = 6.0 \pm 1.3 (stat.) \pm 2.0 (syst.) for Au+Au and (%) = 4.6 \pm 0.4 (stat.) \pm 0.5 (syst.) for Ag+Ag, which are the largest values observed so far. This observation thus provides a continuation of the increasing trend previously observed by STAR and contrasts expectations from recent theoretical calculations predicting a maximum in the region of collision energies about 3 GeV. The observed polarization is of a similar magnitude as predicted by 3D fluid dynamics and the UrQMD plus thermal vorticity model and significantly above results from the AMPT model.Comment: 8 pages, 4 figure

    Obesity-associated GNAS mutations and the melanocortin pathway.

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    This is the final version. Available from Massachusetts Medical Society via the DOI in this record. BACKGROUND: GNAS encodes the Gαs (stimulatory G-protein alpha subunit) protein, which mediates G protein-coupled receptor (GPCR) signaling. GNAS mutations cause developmental delay, short stature, and skeletal abnormalities in a syndrome called Albright's hereditary osteodystrophy. Because of imprinting, mutations on the maternal allele also cause obesity and hormone resistance (pseudohypoparathyroidism). METHODS: We performed exome sequencing and targeted resequencing in 2548 children who presented with severe obesity, and we unexpectedly identified 22 GNAS mutation carriers. We investigated whether the effect of GNAS mutations on melanocortin 4 receptor (MC4R) signaling explains the obesity and whether the variable clinical spectrum in patients might be explained by the results of molecular assays. RESULTS: Almost all GNAS mutations impaired MC4R signaling. A total of 6 of 11 patients who were 12 to 18 years of age had reduced growth. In these patients, mutations disrupted growth hormone-releasing hormone receptor signaling, but growth was unaffected in carriers of mutations that did not affect this signaling pathway (mean standard-deviation score for height, -0.90 vs. 0.75, respectively; P = 0.02). Only 1 of 10 patients who reached final height before or during the study had short stature. GNAS mutations that impaired thyrotropin receptor signaling were associated with developmental delay and with higher thyrotropin levels (mean [±SD], 8.4±4.7 mIU per liter) than those in 340 severely obese children who did not have GNAS mutations (3.9±2.6 mIU per liter; P = 0.004). CONCLUSIONS: Because pathogenic mutations may manifest with obesity alone, screening of children with severe obesity for GNAS deficiency may allow early diagnosis, improving clinical outcomes, and melanocortin agonists may aid in weight loss. GNAS mutations that are identified by means of unbiased genetic testing differentially affect GPCR signaling pathways that contribute to clinical heterogeneity. Monogenic diseases are clinically more variable than their classic descriptions suggest. (Funded by Wellcome and others.).Wellcome TrustWellcome TrustResearch EnglandNational Institute for Health Researc

    The trace fossil Lepidenteron lewesiensis: a taphonomic window on diversity of Late Cretaceous fishes

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    The trace fossil Lepidenteron lewesiensis (Mantell 1822) provides an exceptional taphonomic window to diversity of fishes as shown for the Upper Cretaceous of Poland, in the Middle Turonian–Lower Maastrichtian deposits of the Opole Trough, Miechów Trough, Mazury-Podlasie Homocline, and SE part of the Border Synclinorium. Lepidenteron lewesiensis is an unbranched burrow lined with small fish scales and bones, without a constructed wall. It contains scales, vertebrae, and bones of the head belonging to ten taxa of teleostean fishes: two undetermined teleosteans, six undetermined Clupeocephala, one Dercetidae, and one undetermined euteleostean. The preservation of fish remains suggests that fishes were pulled down into the burrow by an animal, probably by eunicid polychaetes.Das Spurenfossil Lepidenteron lewesiensis (Mantell 1822) ermöglicht einen biostratinomischen Einblick in die Diversität von Fischen, wie Fossilmaterial aus der Oberkreide von Polen zeigt. Es stammt aus dem Mittelturonium bis Untermaastrichtium des südöstlichen Abschnittes der Grenz-Synklinale, dem Opolen-Trog, dem Miechów-Trog und der Masuren-Podlachien-Homoklinale. L. lewesiensis ist ein unverzweigter Grabgang ohne ausgekleidete Wände, dessen Ränder von kleinen Fischschuppen und—knochen gebildet werden. Diese setzen sich aus Schuppen, Wirbel und Schädelknochen von zehn Teleostei-Taxa zusammen und zwar aus zwei unbestimmte Teleosteer, sechs unbestimmten Clupeocephala, einem Dercetidae und einem unbestimmten Euteleostei. Die Erhaltung der Fischüberreste deutet darauf hin, dass die Fische von einem Tier, wahrscheinlich einem Polychaeten der Familie Eunicidae, in den Bau gezogen wurden.We are very grateful to Dr. Lionel Cavin (Geneva) and the anonymous reviewer for constructive comments on an earlier version of the manuscript. Additional support was provided by the Jagiellonian University (DS funds), National Science Center (Grant Number: PRO-2011/01/N/ST10/07717), and the Laboratory of Geology (University of Lodz) BSt Grant No. 560/844. We are grateful to Dr. Johann Egger (Wien) and Kilian Eichenseer M.Sc. (Erlangen) for help with translating the abstract into German. We are grateful to Dr. Ursula Göhlich (Wien) for access to the Dercetis specimen

    Oligocene bivalve faunas from the Silesian Nappe, Polish Outer Carpathians: Evidence for the early history of the Paratethys

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    The study is focused on the taxonomic inventory of an intriguing bivalve fauna from the Lower Oligocene Menilite Beds (Dynów Marls) within the Silesian Nappe, Polish Outer Carpathians. Sixteen bivalve species have been identified within the material collected in two small quarries in Jabłonica Polska near Krosno. Stratigraphic and geographic distributions of all recognized species are considered. This assemblage, the first of this kind in Poland and one of three recognized in the Outer Carpathians, shows clear affinities to coeval typical Solenovian faunas from Ukraine to Kazakhstan, with particular comparison made to bivalve faunas from the Menilite Formation (Subchert Member) within the Boryslav-Pokuttya Nappe, Ukrainian Outer Carpathians. Moreover, this study presents an overview of the main aspects and definitions of the date of the Paratethys origin. The main criterion used to define the time of the Paratethys birth is the distinct faunal turnover from the moderately diverse boreal or Tethyan bivalve faunas populating particular basins of the Northern Peri-Tethys in the earliest Oligocene to the uniform, highly endemic fauna inhabiting the newly formed semi-closed basin. This vast inland sea, named Paratethys, was populated by representatives of eight euryhaline bivalve families. They are characterized by extinct Paratethyan genera, such as Bessia Kojumdgieva et Sapungieva, Merklinicardium Popov, Korobkoviella Merklin, Urbnisia Goncharova, Ergenica G. Popov and Janschinella Merklin
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