Suchergebnisse

Abstract
The role of inflammation in the development of osteoarthritic joint degeneration is not completely understood. Recent data suggest that processes that cause and orchestrate inflamed synovial lesions may be implicated in the development of the disease. The morphological changes of the synovium in patients with osteoarthritis (OA), as well as the level of synovial inflammation cautiously graded, in association to the presence of human parvovirus B19 (B19V) infection markers, were evaluated. Qualitative and quantitative detection of B19V genomic sequence was performed in OA and rheumatoid arthritis (RA) groups. The expression of CD68, S100 (Ca2+ binding proteins soluble in 100% ammonium sulfate) and B19 VP1/VP2 capsid proteins found in the synovium were investigated by single and double immunolabeling, whereas fine features of synoviocytes — by electron microscopy. One-third of OA and RA patients demonstrated synovial expression of B19V antigen, which was confirmed in both types of synoviocytes. The overall expression of B19V in OA patients was weaker than that found in RA subjects. Positive correlation between B19V-positive vascular endothelial cells, sublining infiltrating lymphocytes, macrophages, and B19V-positive synoviocytes was established. No correlation between synovitis score indices as well as the expression of S100 and expression of B19V was found. The results suggest that the synovial membrane maintains local joint homeostasis, and that virus mediated synovitis is implicated in the development of OA.

Abstract
Autoimmune thyroid diseases (AITD) mainly include Hashimoto's thyroiditis (HT) and Graves' disease (GD), which are characterised by the presence of circulating antibodies against various thyroid autoantigens and infiltration of the thyroid gland by autoreactive lymphocytes. Despite the significant advancement in the knowledge of AITD pathogenesis in the last decade, the specific immunological mechanisms responsible for development of the disease are not thoroughly understood. Classically, HT has long been considered as a T helper (Th)1-mediated disease, while a Th2-driven autoimmune response is dominant for GD development. However, this classification has changed due to the description of Th17 lymphocytes, which suggested participation of these cells in AITD, particularly HT pathogenesis. Moreover, a shift in the balance between Th17 and T regulatory (Treg) cells has been observed in thyroid autoimmunity. We have observed overexpression of IL-17, the prominent effector cytokine of Th17, within thyroid tissues from HT and GD patients in our studies. The present review will focus on recent data regarding the role of Treg and Th17 lymphocytes in AITD pathogenesis. In addition, the impact and proposed mechanisms of the predominant environmental factors triggering the autoimmune response to the thyroid will be discussed.

The support from the Latvian Research Program project IMIS 2 (L.S., K.S.) and Latvian Science Council Grant 302/2012 (A.S.) is acknowledged. K.K. was partially supported by the Collaborative Research Project of Materials and Structures Laboratory, Tokyo Institute of Technology. H.H. was supported by the MEXT Element Strategy Initiative to form research cores. ; Chlorine is a common undesirable impurity in synthetic SiO2 glass for ultraviolet optics and optical fibers. It is usually incorporated into glass as bound Si-Cl groups or interstitial Cl2 molecules. We report a high-sensitivity detection of Cl2 in amorphous SiO2 (a-SiO2) by photoluminescence (PL) and also by Raman spectroscopy. The Cl2 PL emission band at 1.22 eV (1016 nm) appears at T < 160 K and shows a characteristic vibronic progression with separations ≈(520-540) cm-1 and an average lifetime of ≈5 ms at 13 K. Its excitation spectrum coincides with the shape of the 3.78 eV (328 nm) optical absorption band of Cl2 in a-SiO2, corresponding to the X → A 1Πu transition to repulsive excited state. Direct X → a singlet-to-triplet excitation was also observed at 2.33 eV (532 nm). Cl2 PL may serve as a sensitive and selective tool for monitoring Cl impurities and their reactions in a-SiO2. A Raman band of Cl2 is found at 546 cm-1. Cl2 photodissociation at energies up to 4.66 eV (266 nm) was not detected, pointing to a strong cage effect in a-SiO2 matrix. However, 7.9 eV (157 nm) photolysis of interstitial O2 molecules gives rise to a Raman band at 954 cm-1, indicating a formation of dichlorine monoxide isomer, ClClO molecule by reaction of O atoms with interstitial Cl2. (Graph Presented). ; IMIS2; Latvian Science Council Grant 302/2012; Tokyo Institute of Technology; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART²

Part 11: New Historiographical Approaches and Methodological Reflections ; International audience ; The article describes the development of information technology in Latvia, in IMCS, to the middle of the 1990s. The history of IMCS represents the usage of computers in typical computing centers in the former Soviet Union and the transformation from computing center to research institution. It also represents Latvian collaboration with the Nordic countries that provided political, scientific, and technological support. Historical documents, computer parts, and photos are collected in the Computer Museum of IMCS.

The support from Latvian Research Program IMIS 2, project "Photonics and materials for photonics" is acknowledged. K.K. was partially supported by the Collaborative Research Project of Materials and Structures Laboratory, Tokyo Institute of Technology. The publication costs of this article were covered by the Estonian Academy of Sciences and the University of Tartu. ; Glassy SiO2 is the basic material for optical fibre waveguides and manufacturing-induced Cl impurities reduce their transparency in UV spectral range. This work reports in-depth study/spectroscopic parameters of the near-infrared (1.23 eV) low-temperature photo-luminescence (PL) of interstitial Cl2 molecules in SiO2. The zero-phonon line position was estimated at 2.075 eV on the basis of anharmonicity of Cl2 PL vibronic data. The vibronic sub-bands are broadened by coupling to phonons and by an additional contribution from the glassy disorder. The Huang‒Rhys factor is ≈13. The PL decay time is between 1 and 10 ms in the temperature range 100 K‒13 K and can be reproduced by 3 exponents. Cl2 PL retains relatively high quantum yield and its characteristic structured shape, when the temperature is increased from 13 K to the liquid nitrogen temperature. This allows using it conveniently as a high-sensitivity diagnostic tool for detecting Cl2 impurities in optical fibre waveguides. Time-resolved measurements of optical fibre waveguides indicate that the lower detection limit is below 1010 Cl2/cm3. ; Tokyo Institute of Technology, MSD K.K.,Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART².

Dieser den Sammelband "Kultur - Ökonomie - Globalisierung" resümierende Beitrag betont, dass die einzelnen Beiträge des Sammelbandes auf unterschiedlichen Ebenen ansetzen und kulturelle Einflussfaktoren auf Bildungssysteme globalen, internationalen, nationalen, subnationalen und lokalen Ursprungs analysieren. Sie verdeutlichen, dass im Mehrebenensystem politischer Interaktion kulturelle Einflussfaktoren wie der Wandel von Werten und Normen im Bereich bildungspolitischer Konzeptualisierung auf allen Ebenen relevante Auswirkungen auf politische Prozesse haben. Effekte der Europäisierung wurden bislang wenig untersucht. (ICE2)

Dieser den Sammelband "Kultur - Ökonomie - Globalisierung" resümierende Beitrag betont, dass die einzelnen Beiträge des Sammelbandes auf unterschiedlichen Ebenen ansetzen und kulturelle Einflussfaktoren auf Bildungssysteme globalen, internationalen, nationalen, subnationalen und lokalen Ursprungs analysieren. Sie verdeutlichen, dass im Mehrebenensystem politischer Interaktion kulturelle Einflussfaktoren wie der Wandel von Werten und Normen im Bereich bildungspolitischer Konzeptualisierung auf allen Ebenen relevante Auswirkungen auf politische Prozesse haben. Effekte der Europäisierung wurden bislang wenig untersucht. (ICE2).

Die Verfasser argumentieren, dass einerseits eine Bezugnahme auf kulturalistische Erklärungsmodelle für den gegenwärtigen Stand der Bildungspolitikforschung nichts Neues ist. Dies zeigen die Hinweise auf "global scripts" und normative internationale Regime, die Nationalstaaten in der Bildungspolitik beeinflussen. Auch müssen Ländergruppeneffekte nicht einzig im Sinne von Kosten und Nutzen determinierenden Sachzwängen in unterschiedlichen Regimen des Wohlfahrtsstaats verstanden werden, sondern können ebenso in Form regimespezifischer normativer Ideengebäude über angemessene Bildungspolitik Eingang in Erklärungsansätze finden. Andererseits wird aber doch eine Analyse-Lücke offenbar, wenn man sich vor Augen führt, dass kulturelle Bezüge vor allem jene Arbeiten setzen, die entweder übernationale Einflussfaktoren auf Bildungspolitik (in der obigen Aufzählung zuerst genannt) oder Ländergruppeneffekte (in der obigen Aufzählung zuletzt genannt) unterstreichen. Spezifische nationale Kulturen als Einflussfaktor auf bildungspolitische Entscheidungsfindung sind demgegenüber bislang unterthematisiert. Auf Basis dieses Einwands ergibt sich eine Reihe an Leitfragen, die dazu dienen, die bisherigen Erklärungsansätze in der Trias aus übernationalen Faktoren, Ländergruppenfaktoren und nationalen Faktoren auf letztgenannter Ebene, der nationalen, zu ergänzen. (ICB2).

Die Verfasser argumentieren, dass einerseits eine Bezugnahme auf kulturalistische Erklärungsmodelle für den gegenwärtigen Stand der Bildungspolitikforschung nichts Neues ist. Dies zeigen die Hinweise auf "global scripts" und normative internationale Regime, die Nationalstaaten in der Bildungspolitik beeinflussen. Auch müssen Ländergruppeneffekte nicht einzig im Sinne von Kosten und Nutzen determinierenden Sachzwängen in unterschiedlichen Regimen des Wohlfahrtsstaats verstanden werden, sondern können ebenso in Form regimespezifischer normativer Ideengebäude über angemessene Bildungspolitik Eingang in Erklärungsansätze finden. Andererseits wird aber doch eine Analyse-Lücke offenbar, wenn man sich vor Augen führt, dass kulturelle Bezüge vor allem jene Arbeiten setzen, die entweder übernationale Einflussfaktoren auf Bildungspolitik (in der obigen Aufzählung zuerst genannt) oder Ländergruppeneffekte (in der obigen Aufzählung zuletzt genannt) unterstreichen. Spezifische nationale Kulturen als Einflussfaktor auf bildungspolitische Entscheidungsfindung sind demgegenüber bislang unterthematisiert. Auf Basis dieses Einwands ergibt sich eine Reihe an Leitfragen, die dazu dienen, die bisherigen Erklärungsansätze in der Trias aus übernationalen Faktoren, Ländergruppenfaktoren und nationalen Faktoren auf letztgenannter Ebene, der nationalen, zu ergänzen. (ICB2)

Financial support provided by Scientific Research Project for Students and Young Researchers Nr. SJZ/2016/12 realized at the Institute of Solid State Physics, University of Latvia is greatly acknowledged. Authors are grateful to R. Ignatans for measurements and analysis of XRD spectra and ElGoo Tech ltd. for providing PEO equipment. ; For decades, plasma electrolytic oxidation (PEO) coatings are actively studied and applied to protect the surface of various valve metals from chemical or mechanical damage. However, over the last couple of years intense research is being done to explore additional possibilities of the PEO coatings apart from their classical application. One of the possible additional uses is thermostimulated luminescence dosimetry that is already widely applied for environmental and health monitoring. This research proposes a method to produce a novel functional coating on aluminium surface exhibiting intense thermostimulated luminescence signal that could be used for dosimetry of ionizing radiation. The result was achieved using plasma electrolytic oxidation with modified electrolyte to introduce carbon ions into the oxide thus inducing defects in the crystalline structure of the coating. Al6082 aluminium alloy was used as a substrate, KOH and ethanol mixture as an electrolyte. A bipolar pulsed regime was used for 15 min. The obtained coating combines the desired luminescence properties with a good mechanical stability due to the relatively hard cubic phase of the coating. Scalability of the technology and low production cost makes the coatings prospective for various practical applications. ; ISSP UL Scientific Research Project for Students and Young Researchers Nr. SJZ/2016/12; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART²

Water quality in cutaway peatland lakes in Seda mire, Latvia
Transformation into shallow lakes can be a major post-harvesting land-use option for cutaway peatlands. The aim of our study was to analyse factors influencing water quality and communities on lakes created in a cutaway bog in the Seda Mire, Latvia. The residual peat amount and the lake feeding conditions (the balance between ground water and inflow from adjacent river during the spring season) were found to be major factors influencing aquatic chemistry and studied habitats. The studied cutaway lakes cannot be considered as typical bog lakes regarding hydrochemical composition (especially regarding concentrations of major dissolved ions, pH and water colour) and hydrobiological features (metabolic activity, biomass and number of species of phytoplankton and zoobenthos). Considering aquatic chemistry and community structure of the cutaway lakes, a recommendation was made in respect to peat excavation to transform peat mining sites to lakes.