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Готові списки джерел за темами / Radical modifications

Добірка наукової літератури з теми "Radical modifications"

Автор: Grafiati

Опубліковано: 13 вересня 2021

Оновлено: 2 лютого 2022

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Статті в журналах з теми "Radical modifications":

1

Chatgilialoglu, Chryssostomos, Carla Ferreri, Albin Hermetter, Emmanuel Lacote, Branka Mihaljević, Athanassios Nicolaides, and Athanassia Siafaka-Kapadai. "Lipidomics and Free Radical Modifications of Lipids." CHIMIA International Journal for Chemistry 62, no. 9 (September 24, 2008): 713–20. http://dx.doi.org/10.2533/chimia.2008.713.

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2

Flejszar, Monika, and Paweł Chmielarz. "Surface Modifications of Poly(Ether Ether Ketone) via Polymerization Methods—Current Status and Future Prospects." Materials 13, no. 4 (February 23, 2020): 999. http://dx.doi.org/10.3390/ma13040999.

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Surface modification of poly(ether ether ketone) (PEEK) aimed at applying it as a bone implant material aroused the unflagging interest of the research community. In view of the development of implantology and the growing demand for new biomaterials, increasing biocompatibility and improving osseointegration are becoming the primary goals of PEEK surface modifications. The main aim of this review is to summarize the use of polymerization methods and various monomers applied for surface modification of PEEK to increase its bioactivity, which is a critical factor for successful applications of biomedical materials. In addition, the future directions of PEEK surface modifications are suggested, pointing to low-ppm surface-initiated atom transfer radical polymerization (SI-ATRP) as a method with unexplored capacity for flat surface modifications.

3

Torreggiani, Tinti, Jurasekova, Capdevila, Saracino, and Foggia. "Structural Lesions of Proteins Connected to Lipid Membrane Damages Caused by Radical Stress: Assessment by Biomimetic Systems and Raman Spectroscopy." Biomolecules 9, no. 12 (November 27, 2019): 794. http://dx.doi.org/10.3390/biom9120794.

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Model systems constituted by proteins and unsaturated lipid vesicles were used to gain more insight into the effects of the propagation of an initial radical damage on protein to the lipid compartment. The latter is based on liposome technology and allows measuring the trans unsaturated fatty acid content as a result of free radical stress on proteins. Two kinds of sulfur-containing proteins were chosen to connect their chemical reactivity with membrane lipid transformation, serum albumins and metallothioneins. Biomimetic systems based on radiation chemistry were used to mimic the protein exposure to different kinds of free radical stress and Raman spectroscopy to shed light on protein structural changes caused by the free radical attack. Among the amino acid residues, Cys is one of the most sensitive residues towards the attack of free radicals, thus suggesting that metal-Cys clusters are good interceptors of reactive species in metallothioneins, together with disulfides moieties in serum albumins. Met is another important site of the attack, in particular under reductive conditions. Tyr and Phe are sensitive to radical stress too, leading to electron transfer reactions or radical-induced modifications of their structures. Finally, modifications in protein folding take place depending on reactive species attacking the protein.

4

Ramirez, Dario C., Sandra E. Gomez-Mejiba, Jean T. Corbett, Leesa J. Deterding, Kenneth B. Tomer, and Ronald P. Mason. "Cu,Zn-superoxide dismutase-driven free radical modifications: copper- and carbonate radical anion-initiated protein radical chemistry." Biochemical Journal 417, no. 1 (December 12, 2008): 341–53. http://dx.doi.org/10.1042/bj20070722.

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The understanding of the mechanism, oxidant(s) involved and how and what protein radicals are produced during the reaction of wild-type SOD1 (Cu,Zn-superoxide dismutase) with H2O2 and their fate is incomplete, but a better understanding of the role of this reaction is needed. We have used immuno-spin trapping and MS analysis to study the protein oxidations driven by human (h) and bovine (b) SOD1 when reacting with H2O2 using HSA (human serum albumin) and mBH (mouse brain homogenate) as target models. In order to gain mechanistic information about this reaction, we considered both copper- and CO3•− (carbonate radical anion)-initiated protein oxidation. We chose experimental conditions that clearly separated SOD1-driven oxidation via CO3•− from that initiated by copper released from the SOD1 active site. In the absence of (bi)carbonate, site-specific radical-mediated fragmentation is produced by SOD1 active-site copper. In the presence of (bi)carbonate and DTPA (diethylenetriaminepenta-acetic acid) (to suppress copper chemistry), CO3•− produced distinct radical sites in both SOD1 and HSA, which caused protein aggregation without causing protein fragmentation. The CO3•− produced by the reaction of hSOD1 with H2O2 also produced distinctive DMPO (5,5-dimethylpyrroline-N-oxide) nitrone adduct-positive protein bands in the mBH. Finally, we propose a biochemical mechanism to explain CO3•− production from CO2, enhanced protein radical formation and protection by (bi)carbonate against H2O2-induced fragmentation of the SOD1 active site. Our present study is important for establishing experimental conditions for studying the molecular mechanism and targets of oxidation during the reverse reaction of SOD1 with H2O2; these results are the first step in analysing the critical targets of SOD1-driven oxidation during pathological processes such as neuroinflammation.

5

Pitt, Andrew R., and Corinne M. Spickett. "Mass spectrometric analysis of HOCl- and free-radical-induced damage to lipids and proteins." Biochemical Society Transactions 36, no. 5 (September 19, 2008): 1077–82. http://dx.doi.org/10.1042/bst0361077.

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In inflammatory diseases, release of oxidants leads to oxidative damage to biomolecules. HOCl (hypochlorous acid), released by the myeloperoxidase/H2O2/Cl− system, can cause formation of phospholipid chlorohydrins, or α-chloro-fatty aldehydes from plasmalogens. It can attack several amino acid residues in proteins, causing post-translational oxidative modifications of proteins, but the formation of 3-chlorotyrosine is one of the most stable markers of HOCl-induced damage. Soft-ionization MS has proved invaluable for detecting the occurrence of oxidative modifications to both phospholipids and proteins, and characterizing the products generated by HOCl-induced attack. For both phospholipids and proteins, the application of advanced mass spectrometric methods such as product or precursor ion scanning and neutral loss analysis can yield information both about the specific nature of the oxidative modification and the biomolecule modified. The ideal is to be able to apply these methods to complex biological or clinical samples, to determine the site-specific modifications of particular cellular components. This is important for understanding disease mechanisms and offers potential for development of novel biomarkers of inflammatory diseases. In the present paper, we review some of the progress that has been made towards this goal.

6

Kasai, Hiroshi, Kazuaki Kawai, and Yun-Shan Li. "Free radical-mediated cytosine C-5 methylation triggers epigenetic changes during carcinogenesis." BioMolecular Concepts 4, no. 3 (June 1, 2013): 213–20. http://dx.doi.org/10.1515/bmc-2012-0052.

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AbstractThe methylation of the C-5 position of deoxycytidine (dC) in the promoter regions of tumor suppressor genes is often observed in cancer cells. We found that various environmental agents, as well as endogenous compounds such as methionine sulfoxide (MetO), generate methyl radicals and modify dC to form 5-methyl-dC in DNA in vitro. We confirmed that both DNA methylation and cancer incidence in the liver were increased by the administration of MetO to oxidatively stressed mice. In this review, we summarize previous reports on methyl radical generation in vitro and in vivo and DNA modifications by methyl radicals, including our discoveries, as well as our recent experimental evidence suggesting that free radical-mediated dC methylation triggers epigenetic changes.

7

Miglietta, Antonella, Elena Gadoni, Claudia Bocca, and Ludovica Gabriel. "Prooxidant Agents Induce Modifications in the Cytoskeletal Organisation of Fibroblasts." Alternatives to Laboratory Animals 24, no. 4 (August 1996): 557–65. http://dx.doi.org/10.1177/026119299602400416.

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An important modulatory role of free-radicals and related species in controlling the cell cycle has recently been revealed. The cytoskeletal system is an intracellular structure that participates in the regulatory mechanisms of the cell cycle and is involved in reactions which generate free-radicals. We studied the effects of three different prooxidant systems (ascorbate/iron II sulphate, adenosine diphosphate/iron III chloride and cumene hydroperoxide) on BALB/C 3T3 fibroblasts, in order to establish a relationship between cytoskeletal alterations and changes in cell proliferation under oxidative stress conditions. We found that prooxidant systems markedly influence cytoskeletal organisation, but only slightly modify the proliferation rate. The mechanism of cytoskeletal alteration is unclear, but does not depend on oxidative damage. The main components of the cytoskeleton appear to be involved in free-radical-generated cell reactions, even though a relationship with cell growth has yet to be identified.

8

Salzano, Anna Maria, Giovanni Renzone, Andrea Scaloni, Armida Torreggiani, Carla Ferreri, and Chryssostomos Chatgilialoglu. "Human serum albumin modifications associated with reductive radical stress." Mol. BioSyst. 7, no. 3 (2011): 889–98. http://dx.doi.org/10.1039/c0mb00223b.

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9

Campolo, Nicolás, Federico M. Issoglio, Darío A. Estrin, Silvina Bartesaghi, and Rafael Radi. "3-Nitrotyrosine and related derivatives in proteins: precursors, radical intermediates and impact in function." Essays in Biochemistry 64, no. 1 (February 2020): 111–33. http://dx.doi.org/10.1042/ebc20190052.

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Abstract Oxidative post-translational modification of proteins by molecular oxygen (O2)- and nitric oxide (•NO)-derived reactive species is a usual process that occurs in mammalian tissues under both physiological and pathological conditions and can exert either regulatory or cytotoxic effects. Although the side chain of several amino acids is prone to experience oxidative modifications, tyrosine residues are one of the preferred targets of one-electron oxidants, given the ability of their phenolic side chain to undergo reversible one-electron oxidation to the relatively stable tyrosyl radical. Naturally occurring as reversible catalytic intermediates at the active site of a variety of enzymes, tyrosyl radicals can also lead to the formation of several stable oxidative products through radical–radical reactions, as is the case of 3-nitrotyrosine (NO2Tyr). The formation of NO2Tyr mainly occurs through the fast reaction between the tyrosyl radical and nitrogen dioxide (•NO2). One of the key endogenous nitrating agents is peroxynitrite (ONOO−), the product of the reaction of superoxide radical (O2•−) with •NO, but ONOO−-independent mechanisms of nitration have been also disclosed. This chemical modification notably affects the physicochemical properties of tyrosine residues and because of this, it can have a remarkable impact on protein structure and function, both in vitro and in vivo. Although low amounts of NO2Tyr are detected under basal conditions, significantly increased levels are found at pathological states related with an overproduction of reactive species, such as cardiovascular and neurodegenerative diseases, inflammation and aging. While NO2Tyr is a well-established stable oxidative stress biomarker and a good predictor of disease progression, its role as a pathogenic mediator has been laboriously defined for just a small number of nitrated proteins and awaits further studies.

10

Ahmad, Safyan, and Muhammad Naeem. "Classes of simplicial complexes which admit nontrivial Cohen-Macaulay modifications." Studia Scientiarum Mathematicarum Hungarica 52, no. 4 (December 2015): 423–33. http://dx.doi.org/10.1556/012.2015.52.4.1317.

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The set of Cohen-Macaulay monomial ideals with a given radical contains the so-called Cohen-Macaulay modifications. Not all Cohen-Macaulay squarefree monomial ideals admit nontrivial Cohen-Macaulay modifications. We present classes of Cohen-Macaulay squarefree monomial ideals with infinitely many nontrivial Cohen-Macaulay modifications.

Більше джерел

Дисертації з теми "Radical modifications":

1

Shuster, Mark D. "Physical and Chemical Modifications of Free Radical Scavengers to Reduce their Radioprotective Potentials for Bacterial Agents." University of Toledo / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1134418758.

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2

Červený, Ladislav. "Reaktivní extruze polymerů s využitím peroxidů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-449699.

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Diploma thesis deals with processing of two types of PP, HDPE, LDPE, PET, PA, PS, PMMA and ABS by reactive extrusion in presence of peroxides. The theoretical part summarizes existing knowledge about processing of used polymers. Reactive extrusion was carried out with a single screw extruder at 260 °C, 30 rpm and 60 rpm depending on peroxide used. One type of PP was processed in presence of Luperox 101, hydrogen peroxide, dicumyl peroxide and potassium persulfate. Luperox 101 and hydrogen peroxide were chosen for reactive extrusion of other polymers. The efficiency of selected peroxides on radical modifications of individual polymers during processing was evaluated by methods of rheological (MFI), structural (FTIR) and thermal (DSC) analysis.

3

Tastet, Damien. "Modulation des propriétés macroscopiques des fibres de pin maritime par polymérisation radicalaire contrôlée amorcée depuis la surface : élaboration de bio-hybrides fonctionnels." Thesis, Pau, 2011. http://www.theses.fr/2011PAUU3026/document.

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Ce travail s’inscrit au sein du projet régional de recherche BEMA (Bois Eco Matériaux Aquitaine) qui allie partenaires universitaires et industriels afin de valoriser, à travers la filière panneaux de particules, des ressources abondantes en Aquitaine : le maïs et le Pin Maritime. L’objectif de cette thèse est de greffer de manière covalente des chaînes de polymère à la surface de fibres de bois afin de modifier leur état de surface et de favoriser leur comptabilisation avec un liant naturel et/ou synthétique. Pour atteindre cet objectif, nous avons choisi d’utiliser une technique de polymérisation particulière, la polymérisation radicalaire contrôlée. Le contexte scientifique international du début de la thèse montre la faisabilité du projet de par la réalisation de plusieurs études sur de la cellulose modèle de type papier filtre. Le défi de cette thèse consiste à transposer ce mécanisme sur des fibres de bois brutes afin de leur conférer de nouvelles propriétés (résistance à l’eau, caractère fongicide, meilleure comptabilisation…). Afin d’atteindre l’objectif énoncé ci-dessus, nous avons développé plusieurs aspects de la chimie des polymères en mettant en oeuvre différentes techniques de synthèse (RAFT, NMP) mais aussi de caractérisation adaptées à la présence de fibres de bois brutes (Mesure d’angle de contact, TGA, XPS). Enfin, nous avons valorisé la présence de polymères fonctionnels en insérant à la surface des fibres de bois des nanoparticules d’oxyde de silice ou de métaux de manière contrôlée
This work is part of the regional research project BEMA (Bois Eco Matériaux Aquitaine) which combines academic and industrial partners to develop, through the wood pannel industry, abundant resources in Aquitaine: corn and Maritime Pine. The objective of this thesis is to covalently graft polymer chains on the surface of wood fibers in order to modify their surface properties and to facilitate their compatibilization with natural and/or synthetic binders. To achieve this goal, we chose to use a special polymerization technique, the controlled radical polymerization. The international scientific context of the beginning of the thesis shows the feasibility of the project through several studies carried out on model cellulose, such as filter paper. The challenge of this thesis is to implement this mechanism on raw wood fibers to give them new properties (water resistance, fungicidal character, best compatibilization ...). To achieve the objective stated above, we investigated several polymer synthetic pathways (RAFT, NMP) but also characterization techniques (Contact angle measurements, TGA, XPS) suitable with the presence of raw wood fibers. What’s more, we have valued the presence of functional polymers by inserting at the wood fibers surface oxide nanoparticles of silica or metal in a controlled manner

4

GONZAGA, Elaine Silva Ferreira. "As práticas de modificações corporais e a formação de identidades somáticas." Universidade Federal de Goiás, 2011. http://repositorio.bc.ufg.br/tede/handle/tde/1407.

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Made available in DSpace on 2014-07-29T15:22:32Z (GMT). No. of bitstreams: 1 Praticas de modificacoes corporais.pdf: 2843245 bytes, checksum: 16e365ecbb2e0403a17bb03ff585867c (MD5) Previous issue date: 2011-09-12
The present study sought to investigate, according to the conception of identities somatic (ORTEGA, 2008), the constitution of subjectivity from the adherents of extreme body modification practices such as tattooing, piercing, scarification, body suspension, among others, concerning the movement of Body Modification. Every age produces a type of body that synthesizes the beauty ideals and values of a society. Recognizing that the supporters of such practices have a body of divergent patterns found in Western society, we tried to reflect not only on the effects of these practices in these individuals, but also about their consequences in society. Sought to identify also the main spreaders of such vehicles as they practice and the socialization of these individuals. For this purpose, presented the main theories about the cultural and symbolic body, identity and subjectivity in the news, as well as a historical background of the rise of the movement of body modification and its specificities. Besides, presented the main aspects on ethnographic research with supporters of these practices in Goiânia. Based on the premise presented by Ortega (2008), that contemporary identities are represented in the body, this movement is valued by the author as a new form of subjectivity and identity, which seeks to find herself in their body image and in its trappings, finding in radical media (DOWNING, 2001) its main propagator.
O presente trabalho procurou investigar, à luz da concepção das identidades somáticas (ORTEGA, 2008), a constituição da subjetividade dos adeptos das práticas de modificação corporal extrema, tais como: tatuagem, piercing, escarificação, suspensão corporal, entre outras, concernentes ao movimento da Body Modification. Cada época produz um tipo de corpo que sintetiza os ideais de beleza e valores de uma sociedade. Reconhecendo que os adeptos de tais práticas possuem um corpo divergente dos padrões presentes na sociedade ocidental, procurou-se refletir não apenas sobre os efeitos destas práticas nestes indivíduos, mas também a respeito de suas consequências na vida em sociedade. Procurou-se identificar, também, os principais veículos disseminadores de tais práticas e como acontece a socialização destes indivíduos. Para tanto, apresentou-se as principais teorias sobre o corpo cultural e simbólico, a identidade e a subjetividade na atualidade, bem como uma contextualização histórica do surgimento do movimento da body modification e suas especificidades. Além disso, foram apresentados os principais aspectos encontrados na pesquisa etnográfica com os adeptos destas práticas em Goiânia. Tendo por base a premissa apresentada por Ortega (2008), de que as identidades contemporâneas são representadas no corpo, este movimento é valorizado pela autora como uma nova forma de subjetivação e identidade, que busca encontrar-se a si mesma na sua imagem corporal e nos seus adornos, encontrando nas mídias radicais (DOWNING, 2001) sua principal propagadora.

5

Ward, Caroline Mary. "Radical reactions for chemoselective modification of peptides /." Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phw2567.pdf.

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6

Wright, Tom. "Post-translational mutagenesis : radical methods for protein modification." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:774aa93a-489e-4051-aa01-b33781215968.

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The naturally occurring post-translational modification of proteins expands the chemical and structural diversity available for protein function. Enzymatic processes are known to modify proteins after translation, and in many cases these modifications have been demonstrated to be critical for biological function. However, the paucity of methods for introduction of site-specific modifications to proteins remains a key obstacle to their biochemical study. Access to these naturally modified proteins has long been complicated by their low abundance, difficulties in purifying homogeneous samples from cellular samples and the intractability of bacterial expression systems towards post-translational modification. In this thesis, we report an important step towards circumventing these issues by using a novel 'tag and modify' chemical strategy, termed 'post-translational mutagenesis'. We describe the development and application of C(sp³)-C(sp³) bond-forming reactions on proteins under biocompatible conditions, exploiting unusual free-radical chemistry to form a wide diversity of protein side-chains. Natural, unnatural, posttranslationally-modified (methylated, glycosylated, phosphorylated, hydroxylated) and labeled (fluorinated, isotopically-labeled) side-chains have been installed on a number of proteins. Extensive characterisation of modification site, connectivity and modified protein structure and function confirm the benign nature of our protocols. The modified proteins thus produced have been used to investigate novel aspects of epigenetic regulation of histone proteins, in the context of free histones and in nucleosome particles, and as novel 'isotope PTMs' for protein characterisation by NMR. We believe this approach, a form of 'protein editing', will have wide application in biochemistry and synthetic biology for accessing diverse modified proteins for research.

7

Georgiev, David Georgiev. "Selective modification of biomolecules using radical mediated hydrothiolation chemistry." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31322.

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Intracellular protein-protein interactions (PPIs) play a vital role in many biological processes. Although they are viewed as of high biological interest they prove difficult to explore as potential targets for drug discovery. Numerous studies have shown α- helical peptides 'locked' in their respective bioactive structure can greatly increase their performance by increasing their target affinity, resistance to proteolysis as well as facilitating cellular uptake. A striking feature of literature to date is how few studies utilise different stapling techniques when developing inhibitors for PPIs. Current methods generally exploit ruthenium catalysed ring closing metathesis (RCM) or copper catalysed alkyne/azide click (CuAAC) chemistry to generate geometrically constrained peptides. Even though these methods have shown great potential they both share a fundamental limitation as the chemistry can only be employed on small synthetic peptides and cannot be extended to larger proteins. Thiol-ene coupling (TEC) chemistry (Chapter 1) which is often described as a 'click' reaction due to its fast reaction rates, high yields, wide functional group tolerance and insensitivity to ambient oxygen and water has the potential to solve this challenge. Thiol-ene chemistry was investigated as an alternative stapling strategy by employing the naturally occurring amino acid L-cysteine (Cys) as a source of the thiyl radical and L-homoallylglycine (Hag), a non-natural amino acid shown to act as a methionine surrogate in protein synthesis to act as a source of an alkene functionality to form a potentially expressible thioether tether in Chapter 2. However, due to unsatisfactory results from the intramolecular thiol-ene cyclisation at the molar concentrations required for peptide or protein modification, and a promising new lead, the closely related thiol-yne reaction was investigated as an alternative in Chapter 3. Using a small library of peptides (14 mers) derived from α-Synuclein (αSyn), a protein mainly found in the presynaptic terminals in the brain and is believed to be key to the pathological progress of Parkinson's disease, a successful macrocyclisation was achieved between the side chains of cysteine (Cys) and homopropargylglycine (Hpg). Although the vinyl-thioether tether did not confer any helical conformation on the stapled peptides, the results clearly demonstrate a potential route for the development of expressible staples. Electron paramagnetic resonance (EPR) spectroscopy in combination with site-directed spin labelling (SDSL) of biomolecules has become a powerful tool for studying the structure and conformational dynamics of biomolecules. Typically, proteins are modified in a site-specific manner by utilising the side chains of cysteine residues to form disulphide bonds with spin active compounds, however, this strategy has its limitations. In Chapter 3 thiol-ene chemistry was investigated as an alternative biorthogonal method to spin label proteins and peptides. The newly synthesised sulfhydryl bearing nitroxide spin label was found to degrade upon exposure to radical promoting conditions, however, an alternative strategy was explored using more classical thiol-Michael chemistry to spin label dehydroalanine (Dha) modified peptides giving the desired spin labelled complex.

8

Mahy, William. "Catalytic synthesis and modification of heterocycles." Thesis, University of Bath, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.687323.

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The following thesis outlines work carried out during the past three years for the discovery and investigation of catalytic methodologies towards the synthesis and modification of heterocycles, namely cyclic carbamates, carbonates and their sulfur analogues. Chapter 1 summarises the current catalytic methods reported in the literature towards the synthesis and modification of functionalized 2-oxazolidinones. This introduction highlights the diverse range of methods and catalysts that have been developed and their scope and limitations. In addition the review highlights the importance of these structural motifs and suggests areas in which the following research fulfills unmet needs. Chapter 2 reports the discovery and development of a one-pot two-step copper-catalysed methodology towards the synthesis of N-aryl oxazolidinones from amino alcohol carbamates. The scope of both the N-aryl substituent as well as oxazolidinone functionalization is presented in addition to preliminary investigations into the mechanisms of both reactions. Chapter 3 presents the application of the previously reported one-pot process towards the synthesis of a number of medicinally active molecules and blockbuster pharmaceuticals. The one-pot two-step copper-catalysed reaction was utilized to synthesise a common intermediate in the synthesis of a number of oxazolidinone-based pharmaceuticals. The complete syntheses of Toloxatone, Linezolid, Tedizolid and Rivaroxaban are reported. Chapter 4 reports the modification of N-aryl oxazolidinones towards a diverse library of N-aryl oxazolidinethiones. The reactivity of these structures, in addition to N-alkyl oxazolidinethiones, towards transition metal catalysis was investigated and revealed a ruthenium catalysed O- to S-alkyl migration to afford structurally diverse thiazolidinones. Investigations into the substrate scope and mechanism were also carried out, suggesting a pseudo-reversible radical pathway drawing mechanistic parallels to the classic Barton-McCombie reaction. Chapter 5 details further development of the pseudo-reversible radical pathway for the regioselective rearrangement of dioxolane-2-thiones using Pd(PPh3)4 as a catalyst. The scope of the reaction is reported for the formation of highly selective, highly substituted sulfur-rearrangement products.

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Clarke, C. S. "Polymorphism and structural modification in some dithiadiazolyl radicals." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597734.

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This thesis opens with a review and summary of the electronic, magnetic and structural properties of 1,2,3,5-dithiadiazolyl radicals, in the context of work presented in this thesis. Chapter 3 describes the synthesis and characterisation of a series of fluoro- and trifluoromethyl-substituted dithiadiazolyl radicals. The third chapter describes a novel synthetic methodology for the preparation of dithiadiazolyl radicals utilising the reaction of an organo-lithium salt (ArLi) with Me₃SiNCNSiMe₃ to generate the key amidinate derivate [ArC(NSiMe₃)₂]Li. This approach has been used to prepare two new dithiadiazolyl radicals bearing CF₃ groups in the ortho-position which lead to monomeric radicals in the solid state; 2,4,6-(CF₃)₃C₆H₂CNSSN (21) and 2,6-(CF₃)₂C₆H₃CNSSN (22). Radical 21 is polymorphic and the magnetic behaviour of both phases has been measured indicating strong antiferromagnetic exchange between radicals in both cases (JI ~ -24 K). Preliminary single crystal EPR studies on 22 are presented. Chapter 4 describes the synthesis and preliminary physical studies on dithiadiazolyl radicals bearing long alkyl or perfluoroalkyl chains which may potentially exhibit liquid crystalline behaviour. Thermodynamic and EPR studies on CF₃(CF₂)₆CNSSN are reported which shows a simple solid-liquid phase transition. In contrast n-C₁₂H₂₅C₆H₄CNSSN exhibits a more complex temperature dependent EPR spectrum suggestive of some pre-melting of the sample consistent with restricted molecular rotation. Chapter 5 describes the crystal structure of a fourth polymorph of C1CNSSN and an unusual co-crystal [2,4,6-(CF₃)₃C₆H₂CNSSN]₄[C1CNSSN]C1 which was isolated during the synthesis of 21. Within the co-crystal the C1^- anion acts as a template forming strong interactions to the disulfide bridge of each dithiadiazolyl ring.

10

Young, Anthony Peter, and Anthony Peter Young. "Characterization of 4-demethylwyosine Synthase, a Radical S-adenosyl-l-methionine Enzyme Involved in the Modification of tRNA." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/621437.

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Wyosine derivatives are highly complex modified ribonucleic acid (RNA) bases found in archaea and eukarya. They are a modification of a genetically encoded guanosine found at position 37 of phenylalanine encoding transfer ribonucleic acid (tRNA). The second step in the biosynthesis of all wyosine derivatives, in both archaea and eukarya, is the transformation of N-methylguanosine to 4-demethylwyosine by the radical S-adenosyl-l-methionine enzyme TYW1. When these studies were initiated, the substrate of TYW1 was unknown. Four possible substrates; acetyl CoA, acetyl phosphate, phosphoenolpyruvate, and pyruvate; were tested for activity. Only incubation with pyruvate led to production of 4-demethylwyosine. As only two new carbons are incorporated into the RNA base at this step, ¹³C isotopologues were used to identify the carbons that are transferred into 4-demethylwyosine. These experiments revealed that C2 and C3 of pyruvate are incorporated into 4-demethylwyosine, with C1 lost as an unknown byproduct. Utilizing pyruvate containing deuteriums in place of protons on the C3 carbon, the regiochemistry of the addition was determined. It was found that C3 forms the methyl group of 4-demethylwyosine and C2 becomes the bridging carbon in the imidazoline ring. The site of hydrogen atom abstraction by 5'-deoxyadenosyl radical was identified as the N-methylguanosine methyl group through the use of tRNA containing a deuterated methyl group. The putative mechanism for this transformation involved the formation of an enzyme substrate Schiff base through a conserved lysine residue. Utilizing sodium cyanoborohydride a Schiff base was trapped between TYW1 and pyruvate. The mass of the trapped adduct responded as expected when different isotopologues of pyruvate were used, demonstrating that it is due to pyruvate. Moreover, the fragment of TYW1 that contained the trapped adduct contained two lysine residues, one of which was shown to be required for activity both in vivo and in vitro. It was initially proposed that TYW1 contained two iron-sulfur clusters, and then subsequently shown to have two 4Fe-4S clusters. Site directed mutagenesis, along with iron and sulfide analysis identified the cysteines; as C26, C39, and C52; coordinating the second 4Fe-4S cluster. This study identified pyruvate as the substrate of TYW1, and provided evidence for key steps in the transformation of N-methylguanosine to 4-demethylwyosine.

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Книги з теми "Radical modifications":

1

Zachhuber, Johannes. The Rise of Christian Theology and the End of Ancient Metaphysics. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198859956.001.0001.

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It has rarely been recognized that the Christian writers of the first millennium pursued an ambitious and exciting philosophical project alongside their engagement in the doctrinal controversies of their age. This book offers for the first time a full analysis of this Patristic philosophy. It shows how it took its distinctive shape in the late fourth century and gives an account of its subsequent development until the time of John of Damascus. The book falls into three main parts. The first of them starts from an analysis of the philosophical project underlying the teaching of the Cappadocian fathers, Basil of Caesarea, Gregory of Nyssa, and Gregory of Nazianzus. This philosophy, arguably the first distinctively Christian theory of being, soon becomes near-universally shared in Eastern Christianity. A few decades after the Cappadocians, all sides in the early Christological controversy take its fundamental tenets for granted. Its application to the Christological problem thus appeared inevitable. Yet it created substantial conceptual problems. Parts II and III of the book describe in detail how these problems led to a series of increasingly radical modifications of the Cappadocian philosophy. The chapters of Part II are dedicated to the miaphysite opponents of the Council of Chalcedon, while Part III discusses the defenders of the Council from the early sixth to the eighth centuries. Through this overview, the book reveals this period as one of remarkable philosophical creativity, fecundity, and innovation.

2

Kiloby, Scott. Natural rest for addiction: A radical approach to recovery through mindfulness & awareness. 2017.

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3

Jaszczolt, Kasia M. Pragmatic indexicals. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198786658.003.0013.

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In this chapter Kasia M. Jaszczolt offers a pragmatic, contextualist account of the meaning of devices used for first-person reference that makes use of the post-Gricean idea of top-down modification of truth-conditional content. On this view, the indexical/non-indexical distinction becomes blurred because expressions on each side of the dichotomy can have indexical as well as non-indexical functions. She demonstrates how indexicality can be ‘pragmaticized’, and how the resulting ‘functional indexicals’ can be represented in her radical contextualist theory of Default Semantics.

4

Lassiter, Daniel. Previous work on graded modality: Lewis and Kratzer. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198701347.003.0003.

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This chapter begins the discussion of graded modality with a review of two influential previous accounts. Lewis’ qualitative theory of comparative goodness begins with an ordinal scale – like those discussed in chapter 2, but composed of propositions rather than individuals. Measurement-theoretic considerations reveal that Lewis’ semantics is inadequate on several fronts, including the interpretation of quantitative comparisons (much better than) and a problematic ‘maximax’ feature that Lewis himself identifies. Kratzer’s proposal – a modification of Lewis’ which extends the account to non-gradable modals and graded epistemics – is presented, along with a compositional implementation using tools developed in ch.2. This theory shares the problems of Lewis’ theory, and adds additional problems due to unified treatment of epistemic and deontic modals. While this unification is methodologically attractive, it is also empirically problematic because epistemic and deontic comparatives generate radically different validities in cases involving disjunction and subset reasoning.

Частини книг з теми "Radical modifications":

1

Palayapalayam Ganapathi, Hariharan, Gabriel Ogaya-Pinies, Eduardo Hernandez, Rafael Coelho, and Vipul R. Patel. "Technical Modifications for Salvage and Complex Radical Prostatectomy." In Robotics in Genitourinary Surgery, 427–41. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-20645-5_30.

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2

Stadtman, E. R., P. E. Starke-Reed, C. N. Oliver, J. M. Carney, and R. A. Floyd. "Protein modification in aging." In Free Radicals and Aging, 64–72. Basel: Birkhäuser Basel, 1992. http://dx.doi.org/10.1007/978-3-0348-7460-1_7.

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3

Woodruff, Shannon R., and Nicolay V. Tsarevsky. "Synthesis of Star Polymers with Epoxide-Containing Highly Branched Cores by Low-Catalyst Concentration Atom Transfer Radical Polymerization and Post-Polymerization Modifications." In ACS Symposium Series, 149–67. Washington, DC: American Chemical Society, 2015. http://dx.doi.org/10.1021/bk-2015-1188.ch011.

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4

Gao, Chao. "Grafting of Polymers on Nanotubes by Atom Transfer Radical Polymerization." In Surface Modification of Nanotube Fillers, 179–213. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527635085.ch9.

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5

Anderson, I. J. "Local Modifications to Radial Basis Networks." In Mathematics of Neural Networks, 73–77. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4615-6099-9_9.

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6

Pinson, Jean. "Functionalization of Polymers by Reaction of Radicals, Nitrenes, and Carbenes." In Surface Modification of Polymers, 241–71. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2019. http://dx.doi.org/10.1002/9783527819249.ch9.

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7

Catalona, William J. "Potency-sparing modification of radical retropubic prostatectomy." In Cancer Treatment and Research, 21–31. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4613-2033-3_3.

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8

Garland, Donita, Paul Russell, and J. Samuel Zigler. "The Oxidative Modification of Lens Proteins." In Oxygen Radicals in Biology and Medicine, 347–52. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4684-5568-7_52.

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9

Caneba, Gerard, and Yadunandan Dar. "Polymer Modification of VA–AA-Based Copolymer Emulsions." In Emulsion-based Free-Radical Retrograde-Precipitation Polymerization, 177–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-19872-4_17.

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10

Jo, Hanju, and Patrick Theato. "Post-polymerization Modification of Surface-Bound Polymers." In Controlled Radical Polymerization at and from Solid Surfaces, 163–92. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/12_2015_315.

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Тези доповідей конференцій з теми "Radical modifications":

1

Cheenkachorn, Kraipat, Wallis A. Lloyd, and Joseph M. Perez. "Use of Pressurized Differential Scanning Calorimetry (PDSC) to Evaluate Effectiveness of Additives in Vegetable Oil Lubricants." In ASME 2003 Internal Combustion Engine Division Spring Technical Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/ices2003-0657.

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Use of renewable resources to replace petroleum base stocks in lubricants is attractive. Research on additives enhanced by current advances in genetic and chemical modifications has resulted in improved oxidative stability of vegetable oils. Like most oxidation processes, the oxidative degradation of vegetable oils is complex. The auto-oxidation free radical mechanisms and hydroperoxide theories of oxidation have been well studied. Factors that influence the degradation of oils include temperature, surface reactivity, rates of formation of radicals, chemical composition factors such as olefin and aromatic content and additive effectiveness. This uses pressurized differential scanning calorimetry to evaluate the oxidative stability of four biodegradable fluids with and without additives. The oleic acid content of the four fluids ranged from 83 to 23 percent. Reaction kinetics are used to explain observed differences in phase transformation and polymerization reactions. Additive selection to obtain maximum effectiveness in the base stocks is reported.

2

Stephan, Patrick M. "Development and Testing of a High Thermal Conductivity Refractory Tile System in a Waste-to-Energy Combustion Unit." In 15th Annual North American Waste-to-Energy Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/nawtec15-008.

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Refractory systems are used for tube wall protection in waste-to-energy (WTE) boilers. Through the years, continuous adjustments have been made to the refractory materials and product designs. Design modifications have incrementally improved tile systems from bolt-on to hidden-clip to back-cast systems. Different refractory types, such as gunning cements and other monolithics, have also been used with varying degrees of success. A new refractory system is currently evolving, borrowed from other advanced high temperature applications and adapted to fit WTE boiler designs. This new system is a radical change in design from conventional refractory systems.

3

Marques, Maria, Carlos Agostinho, and Ricardo Jardim-Gonçalves. "Case-Based Support to Sustainable Interoperability and Decision in Enterprise Networks." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-65704.

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Nowadays companies do not thrive solely through their own individual efforts and isolated knowledge. Enterprises have to become agile, sensitive to changes in market forces, and capable of responding with incremental modifications in business and services provided (adaptation) as well as anticipating radical changes by responding with new and breakthrough business models (innovation). This involves a mix of both cooperative and competitive elements, where decision support, evolving information systems, and the use of networking concepts such as the virtual enterprise or the enterprise ecosystem is becoming more common. The approach here presented aims at facilitating and sustaining interoperability in a dynamic networked enterprise environment. Relying on domain-based semantic translation services, sustainable interoperability enables each organization to keep its own terminology and seamlessly communicate with others (i.e. enterprise interoperability). This work contributes to that paradigm, proposing a novel mechanism based in probabilistic analysis (PA), case-based reasoning (CBR) and similarity calculation (SC) to support decision, service redesign and mapping modifications, e.g. when a company changes its internal model but wants to ensure that communication with external entities is not affected.

4

Gooch, Shayne, Laura Hollingsworth, and Tony Medland. "The Study of the Interaction of Humans With Wheelchairs to Improve the Design." In ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/detc2009-87475.

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In order to evaluate a wheelchair design it is necessary to look at the capabilities of the user and the chair’s intended purpose. Whilst some chairs are only required to provide infrequent mobility indoors, others need to enable the user to travel great distances out doors over rough terrain. In this respect the chair should be considered in the same manner as any other ‘inclusive’ product (or be useable by all). There is a need to better understand the capabilities of different users and how this affects their ability to use a wheelchair for the express purpose required. A detailed experimental investigation was carried out into the wheelchair propulsion characteristics of people with paraplegia and tetraplegia. In this investigation, subjects’ posture, applied forces, and their strategies in applying forces to the wheel rims were studied. Three distinct postures and corresponding techniques were observed and subsequently modelled in a constraint-modelling environment. Here rules were developed that allowed these differing postures to be applied to a manikin representation and their effect upon the wheelchair mobility evaluated. From this study the needs for these classes of individuals were identified in order to allow the wheelchairs to be evaluated. Where conflicts existed between the chair and the user, different modifications in both chair and posture were proposed and assessed. Where no simple modifications exist such a study can provide the basis for a more radical and improved design.

5

Lohrmann, Martin, Horst Bu¨chner, Nikolaos Zarzalis, and Werner Krebs. "Flame Transfer Function Characteristics of Swirl Flames for Gas Turbine Applications." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38113.

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For the suppression or reduction of self-sustained combustion instabilities, modifications of the burner outlet conditions, that strongly influence the dynamic flame response, seem to be the most promising way. Therefore, to derive a detailed physical understanding of the feedback mechanisms the dynamic flame response characteristics, quantified by flame transfer functions, are required in dependence of flame type and operation conditions of the combustor. In the present paper measurements of flame transfer functions of an industrial, full-scale prototype gas turbine burner are discussed. For the detection of periodically-unsteady OH radical radiation (response of the flame) two different UV detection systems were compared. Because the concentration of electronically-excited OH radicals in the reaction zone and therefore, of the measured UV radiation intensity, is strongly depending on volumetric reaction density and local flame temperatures, the UV radiation intensity commonly used for the quantification of the heat release can be misinterpreted. Hence, two different concepts of fuel gas/air mixture formation have been realized in the experiments to separate and to physically interpret the influence of the mixture formation and its quality on the UV radiation intensity of the determined flame transfer functions. The derived understanding of the complex interactions of mixture mass flow oscillations, fluctuations of the mixture composition and the periodic combustion of ring vortices at a full-scale burner is an essential requirement for the interpretation of flame dynamics based on measurements of the UV radiation intensity.

6

Denman, Paul A. "Aerodynamic Evaluation of Double Annular Combustion Systems." In ASME Turbo Expo 2002: Power for Land, Sea, and Air. ASMEDC, 2002. http://dx.doi.org/10.1115/gt2002-30465.

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Legislation controlling the permitted levels of pollutant emissions from aircraft gas turbines has been an increasingly important design driver for the combustion system for some time, particularly with respect to oxides of nitrogen. This has lead to many suggestions for radical departures from the geometry of the classical combustor configuration involving, for example, lean premixed module technology, or staging (axially or radially) of combustor pilot and main zones. The optimum operation of any combustor also requires, however, appropriate and efficient distribution of compressor delivery air to the various flametube features (fuel injectors, dilution ports, for cooling and for air bleed purposes). Radial staging, leading to double annular combustor configurations, poses a particularly difficult challenge. The radial depth of the combustor increases to a level where the external aerodynamics of the combustor involves large flow turning after the pre-diffuser. Careful design is then needed to achieve acceptable levels of loss coefficient in the outer annulus. If these aspects are not properly addressed then inadequate penetration and mixing in the combustor interior can result, rendering low emissions performance impossible. This paper will report on the design, instrumentation and operation of a fully annular isothermal test facility, which has been developed specifically to enable this important issue of external flow quality in double annular combustor systems to be assessed. Representative inlet conditions to the combustion system are generated using a single stage axial compressor; modular construction enables quick and inexpensive changes to components of the combustor (pre-diffuser, cowl shape, liner port locations and geometrical details). Computerised rig control and data acquisition allows the collection of large amounts of high quality data. In addition to the calculation of overall system performance, it is then possible to identify flow mechanisms and loss-producing features in various zones and suggest appropriate modifications.

7

Ezzuldeen, Mustafa M. "Innovative Gas Turbine Engine Cycle Aerothermodynamical Analysis." In ASME 2013 Gas Turbine India Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gtindia2013-3522.

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The gas turbine engine design is fundamentally, taking the air flow into the compressing stage then combustion stage to add energy, and finally extracting energy in the turbine module. This journey of the flow in the engine is in serial connections. Posing the problem of the limiting turbine inlet temperature, the number that all the turbomachinery engineers desperately want to increase by tuning the inlet stages materials, or fine changes onto the blades’ profile or the flow paths. But the significant increase to this temperature lies under more fundamental and radical redesigns to the theory of the gas turbine operation, and its thermodynamical cycle. These principles were considered for long untouchable facts, and stayed lurking from the engineers examining eyes. This paper introduces one of these possibilities by genuine redesign concepts. Backed with CFD analysis, and Thermodynamical feasibility studies to address the potential problems of these modifications. The redesigns include implementing the new concept of the contra-rotating turbine more effectively to reduce the turbine module size, connecting pressurized fluid streams of two counter-rotating compressors in parallel instead of the serial connection, forming a protecting Pressurized shield for the entry turbine stages and, Extracting the energy in the process flow using flows interactions instead of flow-blades interactions.

8

Mariani, Viviana Cocco, and Alvaro Toubes Prata. "Computational Modelling of Fluid Flow in Radial Diffusers With Irregular Boundaries." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-15594.

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Radial diffusers are the basic geometry for the automatic valves in reciprocating hermetic compressors. In the present work numerical solutions for the laminar isocoric flow in radial diffusers are performed to investigate the influence of some geometry modifications on the mass flow, rate and on the resultant force on the valve. The numerical model was able to handle irregular geometries making use of a regular mesh, and was validated through comparisons with experiments. Results are presented in terms of the effective flow and force area of valves which are important efficiency parameters for the modelling and design of reciprocating hermetic compressors. The efficiency parameters are presented and explored in terms of small modification of the valve geometry, for Reynolds numbers varying from 1000 to 2500 and two values of the gap between valve reed and valve seat. The flow was significantly affected by the geometry modifications, indicating that with little effort the performance of automatic valves can be substantialy improved. For instance, with a small chamfer of 5° at the outlet of the valve feeding orifice, the effective force area was increased by 30 percent.

9

Oliveira, Ricardo F., Senhorinha F. C. F. Teixeira, Lui´s F. Silva, Jose´ Carlos Teixeira, and Henedina Antunes. "Design and Development of a New Valve Geometry for Spacer Devices." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-39211.

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Nebulizers such as, Dry Powder Inhalers (DPI’s) and pressurized Metered-Dose Inhalers (pMDI’s), are all equally used in the treatment of asthma. For children, where the asthma incidence is high and where a good coordination between the device actuation and the respiration is needed to use the pMDI, a solution was found with the introduction of an add-on spacer to the pMDI. Because spacers attached to the pMDI are the cheapest and most efficient way to treat asthma in children, it is of the greatest relevance to improve its efficiency. This project, which concerns the study of the spacer geometry, is focused in the study, design and development of new valve geometries to enable a better delivery of the drug to the patient. This study was carried out using the Fluent™ software, from ANSYS. Once the input parameters and models were defined in order to get a realistic computational model, the geometry was optimized. This optimal solution was tested, compared and analyzed against Volumatic® valve, the spacer most widely used in the world. All the models, as well as the results obtained will be analyzed and discussed throughout the paper. It was concluded that some simple modifications, introduced on the shape of the cross-section of the valve geometry, yields radical changes in the air flow behavior. Optimizing the airflow by changing the geometry, reducing the vortex areas, will lower the waste of drug in the spacer, increasing the amount of delivery to the lung.

10

Patel, Ankit Bhai, K. Viswanath, and Dhyanjyoti Deb Nath. "Effect of Axial Sweep and Tip Extension on Performance of an Axial Fan." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-65967.

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Performance enhancement in terms of stall margin increment, increased pressure rise coefficient and increased efficiency is of great need for low speed axial fans. Stacking line modifications in terms of sweep, skew, dihedral or combination of these, as well as blade tip geometry modifications are assumed to be one of the ways to achieve finite performance improvement. Non radial stacking of blade profiles modifies secondary flows, tip vortex effects, hub passage vortex and thus affects aerodynamic performance parameters such as stall margin, efficiency, pressure rise, blade loading. In literature many studies have confined to comparison of few cases which led to conflicting results as modification of stacking line may have different effects in different cases. In the present work, comparison of performance of axial fan rotor with three different blade configurations BSL (baseline), SWP (swept blade) and EXTN (swept blade with extended tip) are considered. The BSL configuration is designed on basis of non-free vortex design. The SWP configuration is obtained by shifting radial stacking line of the BSL in axial flow direction by 10° (Forward sweep). The EXTN configuration is obtained by extending tip profile on pressure surface as well as suction surface by 3% locally. Experiments have been conducted on these three configurations to study effects of these modifications on aerodynamic performance. The flow field has been surveyed using Kiel probe, Three hole pressure probe at many flow rates starting from fully open to fully closed. Unsteady flow analysis at exit of rotors of all configurations is carried out using fast response pressure probe. Experimental results show slight performance improvement in terms of increased stall margin, efficiency, as well as total pressure rise for SWP rotor as well as EXTN rotor compared to BSL rotor at low flow coefficients.

Звіти організацій з теми "Radical modifications":

1

Smith, G., T. Wiltowski, T. Wiltowska, E. Myszka, and Keji Zhao. Modification of coal surfaces with methyl radicals. Office of Scientific and Technical Information (OSTI), March 1990. http://dx.doi.org/10.2172/7183042.

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2

Smith, G. V., T. Wiltowski, J. B. Phillips, and I. Hannus. Modification of coal surfaces with methyl radicals: Final report, January 1--December 31, 1988. Office of Scientific and Technical Information (OSTI), March 1989. http://dx.doi.org/10.2172/6176870.

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3

Technical modifications during radical prostatectomy to speed recovery of urinary incontinence. BJUI Knowledge, September 2018. http://dx.doi.org/10.18591/bjuik.0682.

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