Search results for "PVA"
showing 10 items of 54 documents
The Role of Sirtuin1 in Regulating Endothelial Function, Arterial Remodeling and Vascular Aging
2019
Sirtuin1 (SIRT1), which belongs to a highly conserved family of protein deacetylase, is one of the best-studied sirtuins. SIRT1 is involved in a variety of biological processes, including energy metabolism, cell proliferation and survival, chromatin dynamics, and DNA repair. In the vasculature, SIRT1 is ubiquitously expressed in endothelial cells, smooth muscle cells, and perivascular adipose tissues (PVAT). Endothelial SIRT1 plays a unique role in vasoprotection by regulating a large variety of proteins, including endothelial nitric oxide synthase (eNOS). In endothelial cells, SIRT1 and eNOS regulate each other synergistically through positive feedback mechanisms for the maintenance of end…
Representation of Intimate Partner Violence Against Women in Swedish News Media: A Discourse Analysis.
2020
Despite being rated as some of the world’s most gender equal countries, Sweden and neighboring Nordic nations show high rates of intimate partner violence against women (IPVAW). As the news media contribute to the shaping of public attitudes, this article pursues a two-step discourse analysis of how IPVAW was represented in seven Swedish newspapers during 2018. Although an individualistic discourse on IPVAW was found to be most prevalent, articles where perpetrators were presented as non-Swedish more frequently contained a structural framing of IPVAW. This confirms previously noted tendencies toward individualization and othering of IPVAW in Sweden.
Smiltsērkšķu marafivīrusa kodēto proteīnu klonēšana, ekspresija un raksturošana
2022
Smiltsērķšu marafivīruss (SBuMV) ir iepriekš neraksturots, smiltsērkšķus inficējošs vīruss. Tam ir divas atklātās translācijas fāzes (ORF), kur ORF1 kodē poliproteīnu, kas satur četrus proteīnu domēnus, bet ORF2 kodē apvalka proteīnu (CP). Šajā darbā tika izveidotas ekspresijas plazmīdas SBuMV kodētajiem proteīniem, taču E. coli sistēmā izdevās ekspresēt un attīrīt tikai abas CP formas un proteāzes (PRO) domēnu. Tika pārbaudīta PRO aktivitāte, PRO šķelšanas saits un verificēta PRO deubikvitināzes (DUB) aktivitāte. SBuMV mažorais CP E. coli spēj pašsavākties vīrusam līdzīgajās daļinās (VLP), bet minorais CP veido agregātus. Koekspresijas rezultātā, ja abas CP formas ekspresē no vienas plazmī…
Diffusion coefficient of PVA Fricke gel dosimeters
2015
Fricke gel dosimeters based on various matrix has been studied for a long time as 3D dosimetric system for radiotherapy. Selfoxidation and loss of spatial resolution due to diffusion have been the main issues that have impaired the affirmation of this technique so far. As part of an Italian nation-wide research program, we were interested in develop new gel formulations that are simple, reproducible and non toxic. We studied the one dimensional diffusion coefficient of Fe3+ ions inside Fricke gel dosimeters based on a matrix of PVA cross-linked with a di-aldehyde. With a spectrophotometer equipped with a moving tray we were able to collect absorbance measurements at different positions of t…
Agarose and PVA Fricke gel dosimeters exposed to clinical photons beams: Nuclear Magnetic Resonance Relaxometry and Imaging
2015
Fricke Xylenol Gel (FXG) dosimetric system is based on the radiation induced oxidation of ferrous (Fe2+) to ferric (Fe3+) ions. The application of Fricke gels for ionizing radiation dosimetry is continuously increasing worldwide due to their many favorable properties. However, one of their shortcomings is that ferrous and ferric ions diffuse in the gel matrix. To maintain the spatial integrity of the dose distribution, Fricke gels must be undergoing measurement within a few hours of their irradiation, so that ferric ions remain close to their point of production. Thus, the spatial integrity of the dose distribution in the Fricke gel is maintained. The gel matrix also contributes to the oxid…
Polimēru matricas sfēriskas pildvielas mehānisko īpašību noteikšana netiešā veidā
2015
Polimēru kompozītmateriālam tiek realizēta funkcija mehānisko bojājumu indicēšanai ar vizualizācijas paņēmienu, kurai nepieciešams novērtēt komponenšu fizikālās īpašības. Pamata komponente vizualizēšanas procesā ir mikrokapsulas, kurām elastības moduli ir iespējams noteikt tiešā un netiešā veidā. Tiešā veidā pildvielu elastības moduļa noteikšanai, kad pildviela ir mikro izmēra, ir nepieciešama specifiska aparatūra, bet, lai iegūtu sākuma informāciju un priekšstatu par materiālu, pietiek ar mērīšanu netiešā veidā. Darba mērķis¬¬¬¬¬ ir pēc stiepes eksperimenta datiem noteikt mikrokapsulu elastības moduli netiešā veidā. Kā matrica tika izvēlēta PVA līme. Paraugu fizikālo īpašību noteikšanai, b…
GEL DOSIMETERS FOR RADIOTHERAPY APPLICATIONS: RESULTS OF A “RESEARCH PROJECT OF NATIONAL INTEREST” (PRIN)
2016
Introduction: Gel dosimeters for three-dimensional mapping of radiotherapy doses were introduced at Yale University in the mid-1980’s. Soon after, research and development in this field also started in Italy. Early work was done at the Istituto Superiore di Sanità and at the Universities of Pisa and Milan. Several institutes now collaborate on this topic with the goal of developing new formulations of hydrogel matrices with improved characteristics of stability, sensitivity and spatial resolution compared to those of earlier Fricke-gel and polymer-gel systems. Materials and methods: Contrary to earlier gels based on natural gelling agents, such as porcine skin gelatin and/or agarose, which …
Diffusion and sensitivity characteristics of a chemically cross-linked PVA-Fricke gel dosimeter
2016
Introduction: Current radiotherapy techniques implement treatment plans based on volumetric distributions of dose with complex shapes and sharp gradients. The agreement between these plans and the dose that is truly delivered is very challenging to verify. Thus, there is the need for a dosimetric system that is truly three dimensional, sensitive to radiation in each point and tissue equivalent. In this framework, great interest is encountered by radio-chromic gel dosimeters. In order to address the limitations of gels based on natural matrices, some investigators have proposed dosimeters based on poly vinyl alcohol (PVA) made by freezing-thawing cycles. Even though these gels have a low dif…
Gallija oksīdu saturošu kodola-apvalka nanovadu heterostruktūru sintēze
2021
Darbā tika pētītas un attīstītas fizikālās metodes Ga2O3 nanovadu (NW) audzēšanai un Ga2O3 saturošu NW kodola-apvalka heterostruktūru izveidei ar ķīmisko tvaiku transportu un ar atomāru slāņu kondensācijas (ALD) izveidota slāņa atkvēlināšanu. Eksperimentu laikā iegūtās nanostruktūras raksturoja ar skenējošo un transmisijas elektronu mikroskopu, rentgendifrakciju un enerģētiski dispersīvo rentgenstaru spektroskopiju. Darbs sastāv no literatūras apskata, eksperimentālās daļas, rezultātu analīzes un diskusijas un secinājumu daļas. Darba centrālais pētījuma objekts bija Ga2O3 nanovadi. Ga2O3 šobrīd ir aktīvi pētīts pusvadītājs ar 4.9 eV platu aizliegto zonu un optisko caurlaidību redzamajā gais…
PVA-GTA Fricke gel dosimeters exposed to clinical photons beams: Nuclear Magnetic Resonance Relaxometry and Imaging
2016
Fricke Gel (FXGs) dosimetric system is based on the radiation induced oxidation of ferrous to ferric ions. The application of Fricke gels for ionizing radiation dosimetry is continuously increasing worldwide due to their many favorable properties. However, one of their shortcomings is that ferrous and ferric ions diffuse in the gel matrix. To maintain the spatial integrity of the dose distribution, Fricke gels must be undergoing measurement within a few hours of their irradiation, so that ferric ions remain close to their point of production. Thus, the spatial integrity of the dose distribution in the Fricke gel is maintained (Schreiner, 2015). The gel matrix also contributes to the oxidati…