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Resonance & Resemblance: Sound Perspectives of a Pluralistic World
As we mature into the 21st century the world is experiencing increasing instability in environmental, geopolitical, economic and social realms. To support a more equitable and sustainable politics, feminist new materialist theorists have proposed constructs that reframe our engagement of nature, agency, political and social realms. They work to challenge nature/cultural and subject/object binaries to emphasize a distributed, pluralistic, impactful and interconnected world. However, they have an epistemic blind spot in that their theorizing lacks a diversity of the embedded and creative animation they advocate for. The following dissertation Resonance & Resemblance: Sound Perspectives of a Pluralistic World attends to this need. Through an interdisciplinary methodology this dissertation discusses my proposition that the phenomenon of resonance can be, and has been, engaged to theorize a diverse field of material agency and interconnectedness. It addresses my approach to a component of my research, which was conducted through artistic research practice with the composition Resonance & Resemblance (2017) commissioned by the Russel Wright Historical Foundation. This dissertation also presents work from interlocutors Maryanne Amacher (1943 -2010), Pauline Oliveros (1932 - 2016), and Jacqueline Kiyomi Gordon (b. 1982). Each of these electronic music composers have adopted resonance as a mode of creative engagement to know the materials they work with and their surrounding environment. I analyze the composite of my research through a critical framework that intersects feminist materialisms with agent-environment cognition theory. This intersection of theory progresses an intertextual reading that allows me to locate resonance as a cross-modal mode of interpersonal and intermaterial negotiations to render what I call resonant materialism, an embedded, sensual praxis that reframes issues of difference, material effect and accessibility without separation
Book Note: The Language of the Constitution: A Sourcebook and Guide to the Ideas, Terms, and Vocabulary Used by the Framers of the United States Constitution. by Thurston Greene. Stuart B. Flexner, Editor-In-Chief.
Book note: The Language of the Constitution: A Sourcebook and Guide to the Ideas, Terms, and Vocabulary Used by the Framers of the United States Constitution. By Thurston Greene. Stuart B. Flexner, Editor-in-Chief. Westport, Conn.: Greenwood Press. 1991. Pp. 1074. Reviewed by: Suzanne Thorpe
Aboriginal Community-led Preservice Teacher Education: Learning from Country in the City
In Australia it is well documented that teachers continue to struggle with implementing Aboriginal content, pedagogies and engaging with Aboriginal communities. This paper describes a research project analysing place-based learning for preservice teachers at an urban university led by Aboriginal community members. We argue that place-based learning is critical in developing preservice teacher’s knowledge and confidence in Aboriginal education. Surveys, individual and group yarns provided in-depth data from 64 participants completing elective courses including place-based ‘Learning from Country’ (LFC) experiences. Three key findings emerge from the data. Firstly, the utility of an experiential ‘learning by doing’ approach, secondly, the profound shifts in participant understandings of the diversity of Aboriginal cultures, histories and communities and thirdly, how these experiences highlighted the strength and presence of the local urban Aboriginal community. These findings suggest that LFC holds promise as a pedagogical strategy to improve teacher capacity in Aboriginal education
Inulin-\u3csup\u3e125\u3c/sup\u3eI-Tyramine, an Improved Residualizing Label for Studies on Sites of Catabolism of Circulating Proteins
Residualizing labels for protein, such as dilactitol-125I-tyramine (125I-DLT) and cellobiitol-125I-tyramine, have been used to identify the tissue and cellular sites of catabolism of long-lived plasma proteins, such as albumin, immunoglobulins, and lipoproteins. The radioactive degradation products formed from labeled proteins are relatively large, hydrophilic, resistant to lysosomal hydrolases, and accumulate in lysosomes in the cells involved in degradation of the carrier protein. However, the gradual loss of the catabolites from cells (t1/2 approximately 2 days) has limited the usefulness of residualizing labels in studies on longer lived proteins. We describe here a higher molecular weight (Mr approximately 5000), more efficient residualizing glycoconjugate label, inulin-125I-tyramine (125I-InTn). Attachment of 125I-InTn had no effect on the plasma half-life or tissue sites of catabolism of asialofetuin, fetuin, or rat serum albumin in the rat. The half-life for hepatic retention of degradation products from 125I-InTn-labeled asialofetuin was 5 days, compared to 2.3 days for 125I-DLT-labeled asialofetuin. The whole body half-lives for radioactivity from 125I-InTn-, 125I-DLT-, and 125I-labeled rat serum albumin were 7.5, 4.3, and 2.2 days, respectively. The tissue distribution of degradation products from 125I-InTn-labeled proteins agreed with results of previous studies using 125I-DLT, except that a greater fraction of total degradation products was recovered in tissues. Kinetic analyses indicated that the average half-life for retention of 125I-InTn degradation products in tissues is approximately 5 days and suggested that in vivo there are both slow and rapid routes for release of degradation products from cells. Overall, these experiments indicate that 125I-InTn should provide greater sensitivity and more accurate quantitative information on the sites of catabolism of long-lived circulating proteins in vivo
Nonenzymatically Glucosylated Albumin: In Vitro Preparation and Isolation from Normal Human Serum
Incubation of human serum with D-[6-3H]glucose resulted in the gradual accumulation of radioactivity in acid-precipitable material. Upon chromatography on Sephadex G-200, radioactivity was found associated with each of the major molecular weight classes of serum protein. Purified human serum albumin was also glucosylated in vitro upon exposure to D-[6-3H]glucose in phosphate-buffered saline. The glucosylated and unmodified albumins were separated by ion exchange chromatography. The physiological significance of these observations in vitro was confirmed by the isolation and quantitation of glucosylated albumin from normal human serum. Glucosylated albumin represents approximately 6 to 15% of total serum albumin in normal adults. The post-translational modification appears to occur by a nonenzymatic process analogous to that responsible for glucosylation of hemoglobin A to hemoglobin AIc, i.e. through Schiff base formation and Amadori rearrangement to a ketoamine derivative
Glycation of Amino Groups in Protein
Ribonuclease A has been used as a model protein for studying the specificity of glycation of amino groups in protein under physiological conditions (phosphate buffer, pH 7.4, 37 “C). Incubation of RNase with glucose led to an enhanced rate of inactivation of the enzyme relative to the rate of modification of lysine residues, suggesting preferential modification of active site lysine residues. Sites of glycation of RNase were identified by amino acid analysis of tryptic peptides isolated by reverse-phase high pressure liquid chromatography and phenylboronate affinity chromatography. Schiff base adducts were trapped with Na- BH&N and the a-amino group of Lys-1 was identified as the primary site (80-90%) of initial Schiff base formation on RNase. In contrast, Lys-41 and Lys-7 in the active sitaec counted for about 38 and 29%, respectively, of ketoamine adducts formed via the Amadori rearrangement. Other sites reactive in ketoamine formation included Ne-Lys-1 (15%), N-Lys-1 (9%), and Lys-37 (9%w) hich are adjacent to acidic amino acids. The remaining six lysine residues in RNase, which are located on the surface of the protein, were relatively inactive in forming either the Schiff base or Amadori adduct. Both the equilibrium Schiff base concentration and the rate of the Amadori rearrangement at each site were found to be important in determining the specificity of glycation of RNase
Identification of N epsilon-Carboxymethyllysine as a Degradation Product of Fructoselysine in Glycated Protein
The chemistry of Maillard or browning reactionosf glycated proteins was studied using the model compound, Nu-formyl-W-fructoselysine(f FL), an analog of glycated lysine residues in protein. Incubation of fFL (15 mM) at physiological pH and temperature in 0.2 M phosphate buffer resulted in formation of lVcarboxymethyllysine (CML) in about 40% yield after 15 days. CML was formed by oxidative cleavage of fFL between C-2 and C-3 of the carbohydrate chain and erythronic acid (EA) was identified a s , the split product formed in the reaction. Neither CML nor EA was formed from fFL under a nitrogen atmosphere. The rate of formation of CML was dependent on phosphate concentration in the incubation mixture and the reaction was shown to occur by a free radical mechanism. CML was also identified by amino acid analysis in hydrolysates of both poly-L-lysine and bovine pancreatic ribonuclease glycated in phosphate buffer under air. CML was also detected in human lens proteins and tissue collagens by HPLC and the identification was confirmed by gas chromatography/mass spectroscopy. The presence of both CML and EA in human urine suggests that they are formed by degradation of glycated proteins in vivo. The browning of fFL incubation mixtures proceeded to a greater extent under a nitrogen versus an air atmosphere, suggesting that oxidative degradation of Amadori adducts to form CML may limit the browning reactions of glycated proteins. Since the reaction products, CML and EA, are relatively inert, both chemically and metabolically, oxidative cleavage of Amadori adducts may have a role in limiting the consequences of protein glycation in the body
Role of the Maillard Reaction in Aging of Tissue Proteins: Advanced Glycation End Product-Dependent Increase in Imidazolium Cross-Links in Human Lens Proteins
Dicarbonyl compounds such as glyoxal and methylglyoxal are reactive dicarbonyl intermediates in the nonenzymatic browning and cross-linking of proteins during the Maillard reaction. We describe here the quantification of glyoxal and methylglyoxal-derived imidazolium cross-links in tissue proteins. The imidazolium salt cross-links, glyoxal-lysine dimer (GOLD) and methylglyoxal-lysine dimer (MOLD), were measured by liquid chromatography/mass spectrometry and were present in lens protein at concentrations of 0. 02-0.2 and 0.1-0.8 mmol/mol of lysine, respectively. The lens concentrations of GOLD and MOLD correlated significantly with one another and also increased with lens age. GOLD and MOLD were present at significantly higher concentrations than the fluorescent cross-links pentosidine and dityrosine, identifying them as major Maillard reaction cross-links in lens proteins. Like the N-carboxy-alkyllysines Nepsilon-(carboxymethyl)lysine and Nepsilon-(carboxyethyl)lysine, these cross-links were also detected at lower concentrations in human skin collagen and increased with age in collagen. The presence of GOLD and MOLD in tissue proteins implicates methylglyoxal and glyoxal, either free or protein-bound, as important precursors of protein cross-links formed during Maillard reactions in vivo during aging and in disease
Formation of Pentosidine during Nonenzymatic Browning of Proteins by Glucose
A fluorescent compound has been detected in proteins browned during Maillard reactions with glucose in vitro and shown to be identical to pentosidine, a pentose- derived fluorescent cross-link formed between arginine and lysine residues in collagen (Sell, D. R., and Monnier, V. M. (1989) J. Biol. Chem. 264, 21597- 2 1602). Pentosidine was the major fluorophore formed during nonenzymatic browning of ribonuclease and lysozyme by glucose, but accounted for \u3c1% of nondisulfide cross-links in protein dimers formed during the reaction. Pentosidine was formed in greatest yields in reactions of pentoses with lysine and arginine in model systems but was also formed from glucose, fructose, ascorbate, Amadori compounds, 3-deoxyglucosone, and other sugars. Pentosidine was not formed from peroxidized polyunsaturated fatty acids or malondialdehyde. Its formation from carbohydrates was inhibited under nitrogen or anaerobic conditions and by aminoguanidine, an inhibitor of advanced glycation and browning reactions. Pentosidine was detected in human lens proteins, where its concentration increased gradually with age, but it did not exceed trace concentrations (55 Fmol/mol lysine), even in the 80-year-old lens. Although its precise carbohydrate source in vivo is uncertain and it is present in only trace concentrations in tissue proteins, pentosidine appears to be a useful biomarker for assessing cumulative damage to proteins by nonenzymatic browning reactions with carbohydrates
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