Unlike other essential trace elements that interact with proteins in the form of cofactors, selenium (Se) becomes co-translationally incorporated into the polypeptide chain as part of 21st naturally occurring amino acid, selenocysteine (Sec), encoded by the UGA codon. Any protein that includes Sec in its polypeptide chain is defined as selenoprotein. Members of the selenoproteins family exert various functions and their synthesis depends on specific cofactors and on dietary Se. The Se intake in productive animals such as chickens affect nutrient utilization, production performances, antioxidative status and responses of the immune system. Although several functions of selenoproteins are unknown, many disorders are related to alterations in selenoprotein expression or activity. Selenium insufficiency and polymorphisms or mutations in selenoproteins’ genes and synthesis cofactors are involved in the pathophysiology of many diseases, including cardiovascular disorders, immune dysfunctions, cancer, muscle and bone disorders, endocrine functions and neurological disorders. Finally, heavy metal poisoning decreases mRNA levels of selenoproteins and increases mRNA levels of inflammatory factors, underlying the antagonistic effect of Se. This review is an update on Se dependent antioxidant enzymes, presenting the current state of the art and is focusing on results obtained mainly in chicken.
During the migration of the back arc extension from central to western Greece the Corinth and Patras grabens are being formed. Orthogonal opening of these graben zones is accomplished by WNW listric normal faults and NNE transfer faults which produce an along-axis fragmentation. The listric faults show an increase in the dip of the fault plane westwards as well as a decrease in the maximum extension rate from 50% to the east in the Corinth graben, to 10% to the west in the Patras graben. Similarly, towards the west, P l i e u a t e r n a r y deposits become thinner whereas Pliocene sediments thin-out indicating a westward rift propagation. another orthogonal fault system consisting of NNW and ENE normal faults. These faults have been formed during general uplift behind the orogenic front which has been migrating from western Greece to the Ionian islands. T h e ENE-trending Rio graben which belongs to his orthogonal system connects the Patras graben to the Corinth graben and has subsequently been active as a transfer fault between them.Plio-Quaternary geodynamic processes in central continental Greece are quite similar to those earlier processes observed in the central Aegean region which reflect the initial stage of continental break-up behind a migrating orogenic front.As the back arc extension migrates westwards it is interacting or is being superimposed above
This paper investigates the sedimentological response of the Tertiary Pindos and Mesohellenic Basins to localized tectonic and eustatic sea‐level changes in a submarine setting dominated by turbidite deposition. Five composite stratigraphic cross‐sections were compiled from field data, three in the Pindos Basin and two in the Mesohellenic Basin; 45 samples were dated by means of nannofossil bio stratigraphy. On the basis of these field studies, we relate observed changes in depositional environment to eustatic sea‐level changes and to activity on local thrusts. Between the early Eocene and the late Miocene, tectonically‐driven subsidence in both basins was generally more significant than eustatic variations in controlling depositional patterns. However, depositional conditions can be related to eustatic changes at four specific times: late Eocene submarine fans and deltaic or fan‐delta deposits in the Mesohellenic Basin can be related to a sea‐level rise (NP17) and subsequent fall (NP18‐19), respectively; the development of submarine fans in both basins during the early to middle Oligocene (NP22‐23) can be related to a sea‐level rise; a late Oligocene (NP24‐25) sea‐level fall can be related to more restricted depositional conditions, accompanied by intra‐basinal thrusting in the Pindos Basin and the presence of two indentors in the Mesohellenic Basin; a change from deep‐water (submarine fan) to shallow‐marine deposition during the late Miocene in the Mesohellenic Basin can be related to a eustatic fall in sea‐level. Standard organic geochemical analyses were carried out on 93 samples from both basins, including Rock‐Eval pyrolysis and column and gas chromatography. Preliminary results indicate that the sedimentary sequences in both the Pindos and Mesohellenic Basins may have the potential to generate natural gas.
ZusammenfassungSp~itmioz~ine Sedimentationsprozesse sowie strukturelle Entwicklung ~ndern sich in NW kontinental-Griechenland in E-W Richtung.An der Ionischen Kiiste wurden w~hrend der sp~tmio-z~inen Absenkung des Sedimentationsraumes m~chtige Olisthostrome und intrafoliale Falten gebildet. An der Grenze des Plio/Pleistoz~s wurden flache Uberschiebungen, L6sungsschieferung und NNW bis NNE streichende, ge6ffnete Falten entwickelt. Diese tektonische Strukturen sind das Ergebnis aktiver Plattenkonvergenz zwischen der apulischen lithosph~ren-Platte und der ~g~ischen Platte. W~ihrend der postorogenen Aufhebung sind NNW und ENE streichende Verwerfungen entstanden.Im mittleren Plioz~n wurden im Raum zwischen Ionischem Meer und der Pindos Uberschiebung anf dern gefalteten und teilweise erodierten Untergrund vorwiegend limnisch-terrestrische Sedimente abgelagert. W{ihrend der postorogenen Ausweitung sind Absenkungsr~ume in NNW-und ENE Richtung entstanden. Sie sind vermutlich das Ergebnis von Konvektionsstr6mungen innerhalb der Asthenosph~ire, die durch die Hellenische Subduktion hervorgerufen wurden.Die Krustenausdehnung im )~g~iischen ,~back-arc basin,, hat sich kontinuierlich gegen Westen verlagert, so d~ West-Griechenland zus~itztich yon WNW streichenden Grabenstrukturen weitgehend deformiert ist. AbstractThe post-Miocene sedimentary and structural evolution of NW-continental Greece changes from west to east.In the west, along the Ionian coast, the tectonic activity of the Mio-Pliocene marine sedimentation is reflected in olisthostromes and intrafoliated folds. During the emergence of the area at the Pliocene/Pleistocene boundary, low angle thrusting, dissolution cleavage and open NNW to NNE trending folds, were developed. This horizontal shortening is the result of active plate convergence between the Apulian plate and the Aegean plate. Subsequent vertical movements continuing till the precent, produces mainly NNW and ENE directed faults. *) Authors' address: Dr. Th. DOUTSOS, Dr. N. KONTO-VOULOS and Dr. D. FI~YDAS, Geological Department, University of Patras, Patras, Greece.In the east, between the Ionian coast and Pindus thrust, nonmarine sedimentation began, in the middle Pliocene, on a folded and partially eroded substratum. Long fault bounded intramountaneous basins formed during general uplift and extension in three directions: NNW, ENE and WNW. Extension in both areas, resulting from NNW and ENE faults, is interpreted in terms of the action of upwelling convective currents induced by the Hellenic subduction. As the Aegean back arc extension migrated slowly westwards, the whole study area was gradually affected by WNW trending grabens. R6sum~La partie nord-occidentale de la Grace continentale montre, d'est en ouest, une modification des processus s6dimentaires et structuraux.A l'ouest, le long de la c6te ionienne, la sedimentation marine subsidente tardi-mioc~ne s'est accompagn& de puissants olisthostromes et de plis intrafoliaux. La limite Plioc~ne-Pleistoc~ne a vu se d&elopper des charriages peu inclines et des...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.