Academic literature on the topic 'STMP crosslinking'
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Journal articles on the topic "STMP crosslinking"
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Surini, Silvia, Lusiana Ariani, Kurnia Ss Putri, Hayun Hayun, and Effionora Anwar. "COPROCESSED EXCIPIENTS OF CROSSLINKED AMYLOSE AND XANTHAN GUM FOR USE IN CONTROLLED RELEASE DOSAGE FORMS." International Journal of Applied Pharmaceutics 10, no. 1 (December 20, 2018): 59. http://dx.doi.org/10.22159/ijap.2018.v10s1.13.
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Objective: This study was aimed to obtain a new excipient that can be used as a polymer matrix for the formulation of controlled release dosage forms.Methods: This study used coprocessing and crosslinking methods on amylose and xanthan gum (XG) to obtain a new excipient that can be usedfor controlled release matrix of pharmaceutical dosage forms. The coprocessing step was conducted by drum drying, and the crosslinking step wasprepared using 6 and 12% sodium trimetaphosphate (STMP). The produced novel excipients were characterized in terms of infrared (IR) spectrum,substitution degree, moisture content, swelling index, and gel strength.Results: Our results showed that amylose–XG excipients crosslinked using 6% STMP have greater gel strength and better swelling indexes thanexcipients crosslinked using 12% STMP. All coprocessed excipients exhibited no differences in their IR spectra, whereas the crosslinked excipientsdid, indicating a structural change due to the addition of phosphate groups. Crosslinking amylose–xanthan-coprocessed excipients using 6% STMPproduced degrees of substitution (DSs) of 7–8 phosphates per 100 monomeric subunits. The excipients had a moisture content of 8.21–12.85%, andthe pH of a 1% solution of excipients was 6.21–6.43. In addition, the swelling index and gel strength of the excipient where both amylose and XG werecrosslinked together Were more than 1 where only amylose was crosslinked.Conclusion: The crosslinking amylose–xanthan-coprocessed excipient using 6% STMP is more suitable for use in controlled release dosage forms,particularly when the polymer ratio is 1:1.
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Wang, Hongxia, Yu Liao, Ailiang Wu, Bing Li, Jun Qian, and Fuyuan Ding. "Effect of Sodium Trimetaphosphate on Chitosan-Methylcellulose Composite Films: Physicochemical Properties and Food Packaging Application." Polymers 11, no. 2 (February 20, 2019): 368. http://dx.doi.org/10.3390/polym11020368.
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Environmentally friendly food packaging currently attracts much interest. Sodium trimetaphosphate (STMP) finds specialized applications in food, but it is rarely used as a crosslinking agent. In this study, STMP was used as a crosslinking agent to prepare chitosan/methylcellulose composite films. Both antibacterial and physicochemical properties of the composite film were improved by crosslinking with STMP. The crosslinked films, with good antibacterial activity (~99%), had increased tensile strength, a higher elongation at break, a lower swelling ratio and solubility, and a lower enzymatic degradation than the non-crosslinked films. Furthermore, the crosslinked films showed an excellent preservative effect on fresh-cut wax gourd after three days at room temperature. The obtained films crosslinked by STMP can be potentially applied to the food industry, such as food functional packaging, providing a novel alternative to traditional plastic packages.
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Racksanti, Anucha, Sorapong Janhom, Sittiporn Punyanitya, Ruangsri Watanesk, and Surasak Watanesk. "Crosslinking Density of Silk Fibroin – Rice Starch Hydrogels Modified with Trisodium Trimetaphosphate." Applied Mechanics and Materials 446-447 (November 2013): 366–72. http://dx.doi.org/10.4028/www.scientific.net/amm.446-447.366.
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Silk fibroin (SF) and rice starch (RS) are both biopolymers being non-toxic, biocompatible and biodegradable which can be utilized as hydrogels. The aim of this study was to prepare the SF–RS hydrogels modified with trisodium trimetaphosphate (STMP) and determine its crosslinking density for providing a guideline for preparing better quality absorbable hydrogels. The SF–RS hydrogels modified with various percentages of STMP were prepared by solution casting at pH 12 then neutralized to pH 7. The functional groups and molecular linkages of the hydrogels were investigated by Fourier transform infrared spectrometry (FTIR) and proton nuclear magnetic resonance (1H NMR) spectrometry, respectively. Finally, the crosslinking density of the hydrogels was determined by UV/Vis spectrophotometry via the measurement of the relative amount of methylene blue (RMB) bound to the hydrogels. Results from the FTIR and 1H NMR spectra revealed that linkages within the hydrogels occurred mainly between the O–H groups of RS and the triphosphate groups of STMP. From the MB adsorption study, the crosslinking density of the SF–RS hydrogel with 1.0 %w/w STMP at the 60 min saturation time was approximately 63 %.
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Samoila, Iuliana, Sorina Dinescu, Gratiela Gradisteanu Pircalabioru, Luminita Marutescu, Gheorghe Fundueanu, Magdalena Aflori, and Marieta Constantin. "Pullulan/Poly(Vinyl Alcohol) Composite Hydrogels for Adipose Tissue Engineering." Materials 12, no. 19 (October 1, 2019): 3220. http://dx.doi.org/10.3390/ma12193220.
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Composite hydrogels based on pullulan (HP) and poly(vinyl alcohol) (PVA) were both prepared by simple chemical crosslinking with sodium trimethaphosphate (STMP) or by dual crosslinking (simultaneously chemical crosslinking with STMP and physical crosslinking by freeze-thaw technique). The resulting hydrogels and cryogels were designed for tissue engineering applications. PVA, with two different molecular weights (47,000 and 125,000 g/mol; PVA47 and PVA125, respectively), as well as different P/PVA weight ratios were tested. The physico-chemical characterization of the hydrogels was performed by FTIR spectroscopy and scanning electron microscopy (SEM). The swelling kinetics, dissolution behavior, and degradation profiles in simulated physiological conditions (phosphate buffer at pH 7.4) were investigated. Pullulan concentration and the crosslinking method had significant effects on the pore size, swelling ratio, and degradation profiles. Cryogels exhibit lower swelling capacities than the conventional hydrogels but have better stability against hydrolitic degradation. Biocompatibility of the hydrogels was also investigated by both MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and LDH (lactaten dehydrogenase) assay. The MTT and LDH assays proved that dual crosslinked HP/PVA125 (75:25, w/w) scaffolds are more biocompatible and promote to a greater extent the adhesion and proliferation of L929 murine fibroblast cells than chemically crosslinked HP/PVA47 (50/50, w/w) scaffolds. Moreover, the HP/PVA125 cryogel had the best ability for the adipogenic differentiation of cells. The overall results demonstrated that the HP/PVA composite hydrogels or cryogels are suitable biomaterials for tissue engineering applications.
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Zhu, Wei, Jin Gao, Xiao Gang Li, Jun Li Lin, Han Hui Cao, and Bai Tian Sun. "Mechanical Characteristics of PVA/STMP Hydrogel in Tensile and Unconfined Compression." Applied Mechanics and Materials 157-158 (February 2012): 1372–75. http://dx.doi.org/10.4028/www.scientific.net/amm.157-158.1372.
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Hydrogels based on Poly(vinyl alcohol) (PVA) were synthesized using the combining method of chemical agent and freezing-thawing cycle. Sodium Trimetaphosphate (STMP) is a kind of crosslinking agent in this reaction. The resulting hydrogels were characterized in terms of tensile properties and compression stress-strain testing. The influences of STMP and water content on mechanical properties of hydrogels were investigated. It is suggested that PVA hydrogel has excellent tensile strength, higher elongation at break and viscoelastic materials’ stress-strain curve. Tensile strength of specimens without STMP increases from 4 to 6.8 MPa, as well as elongation increase from 300% to 458%, respectively. When the strain changes from 10% to 50%, tangent compressive modulus dramatically increases from 0.58 to 9.9 MPa for hydrogels with 80wt % water and 0.41 to 5.4 MPa for 85wt % water. Meanwhile, the addition of STMP can further improve the mechanical properties of PVA hydrogel.
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Dulong, Virginie, Renauld Forbice, Eric Condamine, Didier Le Cerf, and Luc Picton. "Pullulan–STMP hydrogels: a way to correlate crosslinking mechanism, structure and physicochemical properties." Polymer Bulletin 67, no. 3 (January 20, 2011): 455–66. http://dx.doi.org/10.1007/s00289-010-0435-2.
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Maulani, Rijanti Rahaju, Asep Hidayat, and Ujang Dinar Husyari. "Effect of dual chemically modified on functional properties of white corn starch." Asia Proceedings of Social Sciences 2, no. 1 (December 2, 2018): 77–80. http://dx.doi.org/10.31580/apss.v2i1.430.
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The purpose of the research was to study functional properties of dual-modified two varieties of white corn starch, namely Anoman and Pulut. Modifications of white corn starch used two treatment factors, namely hydroxypropylation reaction at two levels of propylene oxide concentration (8% and 10%) followed by crosslinking reactions on two combinations of STMP phosphate compounds and STPP (ratio 1%:4% and 2%:5%). The results showed that the dual modification can improve the functional properties of white corn starch Anoman dan Pulut variety compared with its native. The dual modified white corn starches of Anoman variety significantly different with Anoman variety on the characteristic of pasting properties, water absorption capacity, swelling volume, clarity of paste, and freeze thaw stability.
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Rosendo-González, Verónica, Javier Illescas, María del Carmen Díaz-Nava, Yolanda Alvarado-Pérez, and José Juan García-Sánchez. "Synthesis and characterization of clay nanocomposites based on starch." MRS Advances 4, no. 59-60 (2019): 3243–49. http://dx.doi.org/10.1557/adv.2019.403.
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ABSTRACTIn this work, the synthesis of starch-clay nanocomposites was carried out. For this purpose, natural starch was extracted from rice grains and it was characterized by structural and spectrophotometric techniques. Afterwards, it was used as the polymer matrix for the synthesis of nanocomposites crosslinked with different agents: glycerol, citric acid (CA) and sodium trimetaphosphate (STMP). As a reinforcement phase, a natural Mexican clay from the Montmorillonite-type (Mt), was employed, which was modified with a cationic surfactant, hexadecyltrimethylammonium bromide (HDTMA-Br), in order to exchange cations, present in the interlaminar spaces of the raw clay mineral with those of the cationic surfactant; thus, changing its nature from hydrophilic to hydrophobic. Characterization, of both natural and organo-modified clays, was carried out by means of scanning electron microscopy (SEM), to determine the change in morphology between these two minerals; X-ray diffraction analysis (XRD), to obtain the crystalline structure of the organo-modified clay and that of the raw clay mineral (Mt). Also, the Fourier transform infrared spectroscopy (FTIR) was employed to determine materials spectra, and their thermal stability was evaluated by means of the thermogravimetric analysis (TGA). On the other hand, the synthesis of these nanocomposites was performed using different crosslinking agents, glycerol, CA or STMP, in order to identify the effect of them into the final properties of these materials.
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Zhao, Yuelong, Hui Sun, Biao Yang, Baomin Fan, Huijuan Zhang, and Yunxuan Weng. "Enhancement of Mechanical and Barrier Property of Hemicellulose Film via Crosslinking with Sodium Trimetaphosphate." Polymers 13, no. 6 (March 17, 2021): 927. http://dx.doi.org/10.3390/polym13060927.
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Hemicellulose is a kind of biopolymer with abundant resources and excellent biodegradability. Owing to its large number of polar hydroxyls, hemicellulose has a good barrier performance to nonpolar oxygen, making this biopolymer promising as food packaging material. Hydrophilic hydroxyls also make the polymer prone to water absorption, resulting in less satisfied strength especially under humid conditions. Thus, preparation of hemicellulose film with enhanced oxygen and water vapor barrier ability, as well as mechanical strength is still sought after. Herein, sodium trimetaphosphate (STMP) was used as esterification agent to form a crosslinked structure with hemicellulose through esterification reaction to render improved barrier performance by reducing the distance between molecular chains. The thus modified hemicellulose film achieved an oxygen permeability and water vapor permeability of 3.72 cm3 × μm × m−2 × d−1 × kPa−1 and 2.85 × 10−10 × g × m−1 × s−1 × Pa−1, respectively, at the lowest esterification agent addition of 10%. The crosslinked structure also brought good mechanical and thermal properties, with the tensile strength reaching 30 MPa, which is 118% higher than that of the hemicellulose film. Preliminary test of its application in apple preservation showed that the barrier film obtained can effectively slow down the oxidation and dehydration of apples, showing the prospect of application in the field of food packaging.
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Leone, Gemma, Marco Consumi, Simone Pepi, Alessio Pardini, Claudia Bonechi, Gabriella Tamasi, Alessandro Donati, Claudio Rossi, and Agnese Magnani. "Poly-vinyl alcohol (PVA) crosslinked by trisodium trimetaphosphate (STMP) and sodium hexametaphosphate (SHMP): Effect of molecular weight, pH and phosphorylating agent on length of spacing arms, crosslinking density and water interaction." Journal of Molecular Structure 1202 (February 2020): 127264. http://dx.doi.org/10.1016/j.molstruc.2019.127264.
Full textDissertations / Theses on the topic "STMP crosslinking"
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Moreno, Balderrama Juan Ángel. "Phase change materials encapsulation in crosslinked polymer-based monoliths : syntheses, characterization and evaluation of pullulan and black liquor based-monoliths for the encapsulation of phase change materials." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0369/document.
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Le stéarate de butyle, un matériau de changement de phase biosourcé (MCP), a été encapsulés dans des matrices polymères (pullulane, lignine, hémicelluloses) par la technique des émulsions concentrées. Les matrices polymères ont été réticulées avec du trimetaphosphate de sodium (STMP) dans des conditions alcalines afin d’obtenir un réseau poreux interconnecté rigide. L’influence du processus de séchage sur les matériaux composites obtenus a été étudiée, indiquant la lyophilisation comme la technique la plus efficace. Des études de calorimétrie à balayage différentiel (DSC) ont permis de déterminer que l’encapsulation de stéarate de butyle dans des matrices polymères ne modifiait pas ses propriétés thermiques de changement de phase. Des essais de compression mécanique et de résistance à la déformation ont permis d'évaluer le potentiel des monolithes en tant que panneaux de stockage de chaleur installés directement dans des bâtiments et des serres.Les produits de réticulation par le STMP ont été identifiés et caractérisés par RMN solide du31P. Il a ainsi été possible de synthétiser des monolithes ayant différents taux de réticulation afin d’optimiser la formulation d'encapsulation de MCP. Les matrices polymères vidée de tous leurs contenus liquides ont été étudiées par microscopie électronique à balayage afin d’étudier leur structure poreuse (distribution de taille des pores). Cette nouvelle approche d’encapsulation en une étape apparaît comme efficace et devrait permettre un développement important des applications énergétiquesEmulsion-templated polymer based (pullulan, lining and hemicelluloses) monoliths encapsulating butyl stearate as bio-based phase change material (PCM) were synthesized. Polymer-bases were crosslinked with sodium trimetaphosphate (STMP) under alkaline aqueous conditions leading to an interconnected porous network. The influence of the drying process on the obtained composite materials morphology was studied indicating freeze-drying as the most effective technique. Differential Scanning Calorimetry (DSC) studies allow to assess that encapsulation of butyl stearate onto matrices do not alter its phase change thermal properties. Mechanical compression and strain resistance tests allowed to evaluate monoliths potential as heat storage panels installed directly in buildings and greenhouses, STMP crosslinking products were identified by solid-NMR characterization, this allowed to synthetize monoliths at different crosslinking yields to find a formulation that improves PCM encapsulation. Polymer matrices were studied by scanning electron microscopy to identify the pore size distribution obtained in STMP crosslinked materials. This new one-step encapsulating approach appears as efficient and cost-effective and is expected to find a broad development in energy storage applications
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Tsai, Chun-En, and 蔡春恩. "Investigation of Poly(Vinyl Alcohol)-based Proton Conducting Membranes Modified by a Two-step Crosslinking Strategy for DMFCs." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/65f5sy.
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博士國立臺灣科技大學
化學工程系
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The aim of this study was to investigation of poly(vinyl alcohol)-based proton conducting membranes modified by a two-step crosslinking strategy for low temperature DMFCs. Because of its good chemical stability, film-fabrication ability and low cost, PVA was chosen to be the matrix of developed membranes for substitution the Nafion membrane showing high cost and poor barrier of methanol crossover. There were two systems developed in this study. One is synthesizes poly(vinyl alcohol) (PVA)-based polymer electrolyte membranes by a modified two-step crosslinking process involving esterization and acetal ring formation reactions. The other is Poly(styrene sulfonic acid)/poly(vinyl alcohol) proton-conducting membranes with semi-interpenetrating networks (semi-IPNs) were prepared using a previously modified two-step crosslinking strategy. The first work of this study uses sulfosuccinic acid (SSA) as the first crosslinking agent to form an inter-crosslinked structure and a promoting sulfonating agent. Glutaraldehyde (GA) as the second crosslinking agent, reacts with the spare OH group of PVA and forms, not only a dense structure at the outer membrane surface, but also a hydrophobic protective layer. Compare with membranes prepared by a traditional one-step crosslinking process, membranes prepared by the two-step crosslinking process exhibit excellent dissolution resistance in water. The membranes become water-insoluble even at a molar ratio of SO3H/PVA-OH as high as 0.45. Moreover, the synthesized membranes also exhibit high proton conductivities and high methanol permeability resistance. The current study measures highest proton conductivity of 5.3 x 10-2 S cm-1 at room temperature from one of the synthesized membranes, higher than that of the Nafion® membrane. Methanol permeability of the synthesized membranes measures about 3.53 x 10-7 cm2 S-1, about one order of magnitude lower than that of the Nafion® membrane. The other work of this study is investigation of poly(styrene sulfonic acid)/poly(vinyl alcohol) proton-conducting membranes with semi-interpenetrating networks (semi-IPNs) were prepared using a modified two-step crosslinking strategy. We previously employed sulfosuccinic acid (SSA) and glutaraldehyde (GA) as crosslinking agents to form a dense hydrophobic layer at the outer membrane surface. Although the proton conductivity of the resulting membrane increased with the content of SSA, the methanol permeability also increased. In this study it was found that the introduction of a sufonating agent, with a high molecular weight, i.e. poly(styrene sulfonic acid) (PSSA), at a PSSA/poly(vinyl alcohol) (g g−1) ratio greater than 0.72, increased the density of the tangled IPN structures that effectively impede the membrane's permeability to MeOH, while enhancing its proton conductivity. The synthesized semi-IPN membranes exhibited high proton conductivities (up to 5.88 × 10−2 S cm−1 at room temperature, i.e. greater than those of Nafion membranes) and high resistances to MeOH permeation (ca. 1.68 × 10−7 cm2 S−1, that is approximately one order of magnitude lower than that of Nafion membranes).
Book chapters on the topic "STMP crosslinking"
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Nassaralla, Belquiz, and João Nassaralla. "Corneal Collagen Crosslinking with Riboflavin and Ultraviolet-A light Step by Step Technique." In Mastering Corneal Collagen Cross-linking Techniques, 51. Jaypee Brothers Medical Publishers (P) Ltd., 2009. http://dx.doi.org/10.5005/jp/books/10491_10.
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Nassaralla, Belquiz. "Chapter-30 Corneal Collagen Crosslinking with Riboflavin and Ultraviolet�A Light: Step by Step Technique." In Surgical Techniques in Ophthalmology Refractive Surgery, 169–73. Jaypee Brothers Medical Publishers (P) Ltd., 2010. http://dx.doi.org/10.5005/jp/books/10885_30.
Full textConference papers on the topic "STMP crosslinking"
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Geisler, Chris G., Ho-Lung Li, David M. Wootton, Peter I. Lelkes, and Jack G. Zhou. "Soft Biomaterial Study for 3-D Tissue Scaffold Printing." In ASME 2010 International Manufacturing Science and Engineering Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/msec2010-34274.
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In 3-D scaffold printing, it is critical to find a material that is suitable for your printing method, printing speed, and ease of use. For a biomaterial to best suit solid freeform fabrication techniques, it must: 1) be a low-viscous solution before being printed, 2) involve easily joined on-substrate mixing to form a homogenous gel, 3) have a short solution to gel transition time, 4) be a mechanically strong gel, and 5) have an irreversible gelation processes. Ionic crosslinkable, photocrosslinkable, and thermo-sensitive hydrogels have all been investigated and found to not fully satisfy our every requirement for SFF printing. Ionic crosslinking hydrogels can gel rapidly but tend to involve additional steps for crosslinking like freeze drying, stirring, and shaking, while some form beads, not homogenous gels. Some photocrosslinkable hydrogels would not work due to the concern for viability of cells in initial gel layers receiving copious amount of UV light. Thermosensitive hydrogels meet most of the requirements except that they are reversible gels. A new type of gel that obtains the qualities of a photocrosslinkable and thermosensitive hydrogel satisfies every requirement. A PEG-PLGA-PEG thermosensitive triblock copolymer additionally crosslinked with photocrosslinkable Irgacure 2959 allows for quick transition from solution to gel with a post-processing step utilizing UV light would add additional crosslinks to the gel structure resulting in an irreversible hydrogel.
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Paviet, Patricia. "Generation IV International Forum Education and Training Webinars: Education Tools for the Next Generation Workforce." In 2018 26th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icone26-81027.
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The Gen IV International Forum (GIF) Education and Training Task Force was created to respond to the challenge of not only forming, training and/or retaining qualified Gen IV workforce but also educating and informing a more general public, policy makers on topics related to Gen IV reactor systems and cross-cutting subjects. The task force serves as a platform to enhance open education and training as well as communication and networking in support of GIF, and its objectives are to maintain the know-how in this field, to increase the knowledge of new advanced concepts, and to avoid the loss of the knowledge and competences that could seriously and adversely affect the future of nuclear energy. While many countries are either ramping up or developing nuclear power production as an important step towards economic development and environmental protection, a decrease or uncertainty of the fiscal year budgets have left organizations and agencies looking for new avenues for training and educating a qualified workforce. This has led to an increase in those looking for readily available education and training resources. Using modern internet technologies, the GIF Education and Training Task Force has launched a webinar series on Gen IV systems in September 2016, which is accessible to a broad audience and is educating and strengthening the knowledge of participants in applications to advanced reactors. This achievement is the direct result of partnering with university professors and subject matter experts who conduct live webinars on a monthly basis. The live webinars are recorded and archived as an online educational resource to the public from the GIF website (www.gen-4.org). In addition, the webinars offer unprecedented opportunities for interdisciplinary crosslinking and collaboration in education and research. The GIF webinars, with their expansion of topics, targets a large spectrum of those that do not know but are desiring to learn about the many aspects of advanced reactor systems. The details and examples of the GIF webinar modules will be presented in our paper.
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Achyuthan, K. E., M. J. Borowitz, M. A. Shuman, and C. S. Greenberg. "THROMBIN INDEPENDENT TRANSGLUTAMINASE IN VASCULAR CELLS AND TISSUES MAY PROVIDE AN ALTERNATE PATHWAY TOWARD CLOT STABILIZATION." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643775.
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Blood coagulation Factor XIIla (FXIIIa) is a thrombin activated transglutaminase (TG) that is involved in the final step of fibrin stabilization. FXIIIa inhibits fibrinolysis by crosslinking α-2-plasmin inhibitor (α-2-PI) to fibrin. A thrombin-independent TG has been identified in vascular cells and tissues -from human, rabbit, rat, porcine and bovine sources. The vascular TG had several properties similar to the well characterized guinea pig liver TG. Both enzymes had similar molecular weights (80-90 kDa) and similar chromatographic and electrophoretic properties. Both enzymes preferentially crosslinked α-chains of fibrinogen and their TG activities were independent of thrombin treatment. Finally, both enzymes reacted with polyclonal and monoclonal antibodies to guinea pig liver TG. However, the TG from cultured adult bovine aortic endothelial (ABAE) cells exhibited a novel Ca++/Mg++ dependence for enzymatic activity which was distinct from purified liver TG. TG from confluent ABAE cells and rabbit vascular smooth muscle cells had between 4-7 fold higher TG activity compared to rapidly dividing (nonconfluent) cells -from the same passage. The difference in activity was not due to enhanced degradation of TG catalyzed isopeptide bonds by nonconfluent cells Upon examination by immunoblots using anti-TG antibodies, the TG antigen in nonconfluent cells appeared extensively degraded. Furthermore, guanosine-5'-triphosphate (GTP) was nearly 3-fold more inhibitory to TG from confluent cells compared to nonconfluent cells. Proteases, GTP and divalent cation levels may be modulating intracellular TG activity. The TG antigen detected by imm-unohistochemical techniques was predominantly associated with endothelial and smooth muscle cells of arteries, veins, venules and capillaries. TG antigen also codistributed with fibronectin antigen along the hepatic sinusoids. The ABAE cell TG crosslinked α-2-PI to fibrinogen. The modified fibrinogen was 40-fold more resistant to plasminolysis compared to unmodified fibrinogen. In conclusion, the presence of a thrombin-independent TG in blood vessels may provide an alternate pathway to inhibit fibrinolysis and promote clot stabilization.