Sökning: "Per E. Ahlberg"

Hittade 4 avhandlingar innehållade orden Per E. Ahlberg.

  1. 1. Silurian vertebrates of Gotland (Sweden) and the Baltic Basin

    Författare :Oskar Bremer; Henning Blom; Per E. Ahlberg; Tiiu Märss; Héctor Botella; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; early vertebrates; vertebrate microremains; scale taxonomy; early vertebrate distribution; environmental preferences; Silurian; Baltic Basin; Gotland; Sweden; Biology with specialization in Evolutionary Organismal Biology; Biologi med inriktning mot evolutionär organismbiologi;

    Sammanfattning : During the Silurian, the Swedish island Gotland was positioned close to the equator and covered by a shallow sea called the Baltic Basin. The sedimentary rocks (predominantly carbonates) comprising most of the island today were initially formed in this warm sea, and the relatively complete succession of rocks often contains fossil fragments and scales from early vertebrates, including heterostracans, anaspids, thelodonts, osteostracans, acanthodians, and a stem-osteichthyan. LÄS MER

  2. 2. Endocranial Morphology and Phylogeny of Palaeozoic Gnathostomes (Jawed Vertebrates)

    Författare :Martin D. Brazeau; Per Ahlberg; Graham Budd; Henning Blom; Michael Coates; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; systematics; palaeontology; anatomy; evolution; Organism biology; Organismbiologi;

    Sammanfattning : Gnathostomes, or jawed vertebrates, make up the overwhelming majority of modern vertebrate diversity. Among living vertebrates, they comprise the chondrichthyans (“cartilaginous fishes” such as sharks, skates, rays, chimaeras) and the osteichthyans (“bony fishes” or bony vertebrates, inclusive of tetrapods). LÄS MER

  3. 3. Who ate whom? Paleoecology revealed through synchrotron microtomography of coprolites (fossil feces)

    Författare :Martin Qvarnström; Živilė Žigaitė; Grzegorz Niedźwiedzki; Per Ahlberg; Karen Chin; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; coprolites; paleoecology; synchrotron microtomography; taphonomy; Triassic; Biologi; Biology;

    Sammanfattning : Fossil droppings, known as coprolites, are being increasingly recognized as a valuable source of paleoecological information with special regard to diets, parasitism, and physiology of extinct taxa. Here, it is suggested that the excellent preservation and amount of inclusions in the coprolites (e.g. LÄS MER

  4. 4. The Human Y chromosome and its role in the developing male nervous system

    Författare :Martin M. Johansson; David Skuse; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MSY; sex differences; CNV; SNP; palindrome; palindromes; gr gr duplication; gr gr deletion; b2 b3 deletion; b2 b3 duplication; blue-grey duplication; blue-grey like duplication; IR2; U3; STS; AZFa; AZFb; AZFc; Olivary nucleus; Medulla oblongata; spinal cord; white matter; Affymetrix 6.0; embryo; embryonal; haplogroup; haplogroups; R1a; R1b; R-M207; E-M96; I-M170; J-M304; G-M201; Ashkenazi; Bolivian; Chinese; SNP array; padlock probing; AMY-tree; Biologi med inriktning mot zoologisk utvecklingsbiologi; Biology with specialization in Animal Development;

    Sammanfattning : Recent research demonstrated that besides a role in sex determination and male fertility, the Y chromosome is involved in additional functions including prostate cancer, sex-specific effects on the brain and behaviour, graft-versus-host disease, nociception, aggression and autoimmune diseases. The results presented in this thesis include an analysis of sex-biased genes encoded on the X and Y chromosomes of rodents. LÄS MER