Naresuan University Journal
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Trade unions, special structures and the inclusion of migrant workers: on the role of union democracy
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The LOFAR Multifrequency Snapshot Sky Survey (MSSS). I. Survey description and first results
No full textWe present the Multifrequency Snapshot Sky Survey (MSSS), the first northern-sky Low Frequency Array (LOFAR) imaging survey. In this introductory paper, we first describe in detail the motivation and design of the survey. Compared to previous radio surveys, MSSS is exceptional due to its intrinsic multifrequency nature providing information about the spectral properties of the detected sources over more than two octaves (from 30 to 160 MHz). The broadband frequency coverage, together with the fast survey speed generated by LOFAR's multibeaming capabilities, make MSSS the first survey of the sort anticipated to be carried out with the forthcoming Square Kilometre Array (SKA). Two of the sixteen frequency bands included in the survey were chosen to exactly overlap the frequency coverage of large-area Very Large Array (VLA) and Giant Metrewave Radio Telescope (GMRT) surveys at 74 MHz and 151 MHz respectively. The survey performance is illustrated within the MSSS Verification Field (MVF), a region of 100 square degrees centered at (α,δ)J2000 = (15h,69°). The MSSS results from the MVF are compared with previous radio survey catalogs. We assess the flux and astrometric uncertainties in the catalog, as well as the completeness and reliability considering our source finding strategy. We determine the 90% completeness levels within the MVF to be 100 mJy at 135 MHz with 108″ resolution, and 550 mJy at 50 MHz with 166″ resolution. Images and catalogs for the full survey, expected to contain 150 000-200 000 sources, will be released to a public web server. We outline the plans for the ongoing production of the final survey products, and the ultimate public release of images and source catalogs
An honorific gnome of the koinon of the Phrikyladai: a new inscription from Liverpool
No full textThis article publishes a new decree from the storerooms of Liverpool’s World Museum. We provide a text and translation of the document, and discuss difficulties in reading the text as well as restorations where the stone is illegible. We offer an approximate dating of the document to the mid-third century, and suggest, on prosopographical and formulaic grounds, that it derives from Erythrae. We offer an interpretation of the status of the transaction (which describes itself as a gnome), the officials mentioned in the document, and the activities and nature of the Phrikyladai
Neuro-muscular regeneration using scaffolds with mesenchimal stem cells (MSCs) isolated from human umbilical cord wharton's jelly: functional and morphological analysis using rat sciatic nerve neurotmesis injury model
No full textPeripheral nerves possess the capacity of self-regeneration after traumatic injury but the extent of regeneration is often poor and may benefit from exogenous factors that enhance growth. Neonatal tissues are routinely discarded at parturition so little ethical controversy attends the harvest of the Mesenchymal Stem Cells (MSCs) which may play an important therapeutic role through the secretion of soluble trophic factors which enhance and assist in repair by paracrine activation of surrounding cells. The use of cellular systems is a rational approach for delivering neurotrophic factors at the nerve lesion site, and in our recent research work we have been evaluating the therapeutic value of MSCs isolated from the Wharton jelly (WJ) in nerve repair associated to different tube-guides made of biodegradable and biocompatible biomaterials. The WJ MSCs in vitro studies included cell characterization by immunocytochemistry, karyotype analysis, tri-lineage differentiation capacity and flow cytometry and also citocompatibility by measuring the intracellular calcium concentration ([Ca2+]i) in the presence of different tube-guides. Biomaterials like PVA, PVA loaded with MWCNTs (functionalized carbon nanotubes, PVA-CNTs), PVA loaded with polypyrrole (PVA-PPy), and PLC associated to MSCs were tested in terms of cytocompatibility and in vivo in the rat sciatic nerve neurotmesis injury model. The regenerated nerves and tibialis anterior (TA) muscles were processed for stereological studies after 20 weeks. The functional recovery was assessed serially for gait biomechanical analysis, by EPT, SFI and SSI, and by WRL. Histopathology of lung, liver, kidneys, regional lymph nodes ensured the biomaterials biocompatibility. The karyotype analysis of the MSCs excluded the presence of neoplastic signs, thus supporting the suitability of isolation and expansion protocols. The MSCs were positive for C-kit, Nanog and vimentin, and negative for CD31, following the International Society for Cellular Therapy (ISCT) definition. Results obtained from epifluorescence by measuring the [Ca2+]i of the MSCs cultured on tube-guides confirmed the ability to support their expansion, adhesion, and differentiation. Our results showed that the use of MSCs enhanced the recovery of sensory and motor function in neurotmesis injuries showing a thicker myelin sheath. MSCs isolated from WJ delivered through biomaterials should be regarded as a potentially valuable tool to improve clinical outcome especially after trauma to sensory nerves. In addition, these cells represent a non controversial source of primitive mesenchymal progenitor cells that can be harvested after birth, cryogenically stored, thawed, and expanded for therapeutic uses
Measurement of the forward-backward asymmetry of electron and muon pair-production in collisions at = 7 TeV with the ATLAS detector
No full textEffect of Platinum Addition on Oxidation Behaviour of γ/γ’ Nickel Aluminide
No full textBulk γ/γ′ nickel aluminide alloys of composition (in at.%) Ni–20Al with the addition of 0, 5, 10 and 15Pt were fabricated using arc melting, and the microstructure of the alloys was characterized. The oxidation behaviours of the alloys at 1150 °C were studied and compared in terms of oxide spallation, oxide microstructure and growth, residual stress in the α-Al2O3 scale and oxide/alloy interface morphology. Progressively increased platinum addition into the alloys results in (1) improvement in the resistance to oxide spallation, (2) reduction in oxidation of nickel, (3) lower stresses in the α-Al2O3 scale and (4) more planar oxide/alloy interfaces. In addition, for short-time oxidation (⩽1 h), the stresses in the α-Al2O3 scale on the γ′ phase region of the alloy are lower than those on the γ/γ′ mixed phase region. Discussion on the platinum effect has been focused on selective oxidation of the alloy and stress development in the oxide scale. It is concluded that the selective oxidation of aluminium promoted by platinum plays a crucial role in the evolution of the oxidation behaviour with the platinum addition
