Scheduling of music classes in small high schools of the United States

Thesis (D.M.A.)--Boston Universit

Effect of Glycosylation on the in Vivo Circulating Half-Life of Ribonuclease

The circulating half-lives of the four isozymes of bovine pancreatic ribonuclease (RNases A, B, C, and D) have been determined in normal and in nephrectomized rats. The isozymes differ only in their glycosyl content. While A contains no sugars, B has a simple oligosaccharide (GlcNAc, Man,+), and C and D each have a complex oligosaccharide (GlcNAc, Man,., Gal, Fuc NeuAc%, and GlcNAc, Mans Gal, Fuc NeuAc,, respectively) attached to Asn-34 of the polypeptide chain. All four isozymes were cleared rapidly in normal rats (t,,, = 2 to 3 min), as expected on the basis of the established role of the kidneys in removing low molecular weight proteins from circulation. In nephrectomized rats, however, a much slower clearance was observed, thus permitting the evaluation of the role of the carbohydrate chains in the catabolism of the isozymes. The clearance curves can be analyzed in terms of two processes, a rapid initial one, shown to represent the equilibration of the injected enzyme into extravascular space, and a second one which is interpreted as the catabolic clearance of the enzyme. The half-life of the RNase isozymes was calculated from this second process and found to be in the range 528 to 577 min for RNase A, 15 min for RNase B, 681 to 862 min for RNase C, and 839 to 941 min for RNase D. The rapidly cleared RNase B was treated with cu-mannosidase to remove 3 of the 4 mannosyl residues, leaving only a trisaccharide (GlcNAc,-PMan) attached to the protein. The half-life of this RNase B derivative was found to be in the range 616 to 733 min. From these results it is concluded (a) that the addition of complex oligosaccharides to a protein does not have any significant direct effect on its circulating half-life (RNases C and D compared to RNase A), and (b) that in the rat there exists a mechanism for clearing glycoproteins based on specific recognition of exposed oc-mannosyl residues (RNase B compared to the other isozymes and to cY-mannosidase-treated RNase B)

Cardiac and renal function are progressively impaired with aging in Zucker diabetic fatty type II diabetic rats

This study investigated the temporal relationship between cardiomyopathy and renal pathology in the type II diabetic Zucker diabetic fatty (ZDF) rat. We hypothesized that changes in renal function will precede the development of cardiac dysfunction in the ZDF rat. Animals (10 weeks old) were divided into four experimental groups: Lean Control (fa/?) LC (n = 7), untreated ZDF rats (n = 7) sacrificed at 16 weeks of age, and LC (n = 7) untreated ZDF rats (n = 9) sacrificed at 36 weeks of age. LV structural/functional parameters were assessed via Millar conductance catheter. Renal function was evaluated via markers of proteinuria and evidence of hydronephrosis. LV mass was significantly less in the ZDF groups at both time points compared to age-matched LC. End diastolic volume was increased by 16% at 16 weeks and by 37% at 36 weeks of age (p < 0.05 vs. LC). End diastolic pressure and end systolic volume were significantly increased (42% and 27% respectively) at 36 weeks of age in the ZDF compared to LC. Kidney weights were significantly increased at both 16 and 36 week in ZDF animals (p < 0.05 vs. LC). Increased urinary albumin and decreased urinary creatinine were paralleled by a marked progression in the severity of hydronephrosis from 16 to 36 weeks of age in the ZDF group. In summary, there is evidence of progressive structural and functional changes in both the heart and kidney, starting as early as 16 weeks, without evidence that one pathology precedes or causes the other in the ZDF model of type II diabetes

Bringing agroforestry technology to farmers in the Philippines: A comparison of two extension assistance regimes

The response of farmers to personalised forestry and agroforestry extension assistance has not been well documented in the Philippines, thus providing the impetus for this research in which the effectiveness of extended on-farm assistance was compared with more limited assistance. In four municipalities on Leyte Island, farmers responded positively to an extended program which helped them overcome problems in germinating and growing seedlings and establishing trees on their land. A limited assistance program which sought to make use of farmers’ familiarity with growing and raising plants was relatively unsuccessful, with lower preparation of tree planting sites and a higher rate of abandonment. Allowing farmers freedom to select aspects of technical advice which suited their personal circumstances, encouraged a high degree of cooperation between extension staff and farmers, but some farmers employed poor tree establishment techniques and some sites were inappropriate for growing trees. Destruction of sites by flooding and grazing also caused farmers to blame extension staff even though these risks had been discussed with them beforehand. This suggested that a more interventionist approach would be appropriate for site selection although it may reduce recruitment. The number of farmers recruited through local government staff was low, but attendance by neighbours at locally held demonstrations was high, suggesting an avenue for further recruitment. Overall, the program was successful in shifting the initiative for further planting from extension staff to those farmers who received extended extension assistance

A Concept of Operations for Earth Science Data Archive and Distribution in the Cloud

Science data systems can enable more comprehensive Earth system research by evolving to take advantage of advances in commercial computer technology services. Since their inception twenty five years ago, NASA's Earth Observing System Data and Information System (EOSDIS) Distributed Active Archive Centers (DAACs) have periodically evolved to utilize new technology and expand research using the exponential growth and diversity of Earth observations. Recently, with the advent of a maturing commercial compute services industry and upcoming high data volume missions such as the Surface Water and Ocean Topography (SWOT) mission and the NASA-Indian Space Research Organization Synthetic Aperture Radar (NISAR) mission, options were explored and a decision made to utilize commercial compute and storage services. This paper presents an overview of the concept of operations under development for the DAACs in the Cloud. We highlight the goals and expected advantages of utilizing Cloud services. We outline EOSDIS operations tenets and driving principles. A high-level view of EOSDIS system of systems target architecture serves as context for describing principle interactions. Concepts for key DAAC system and EOSDIS enterprise functions characterize automated end-to-end operations but mark nominal check and recovery points. Concepts are presented for managing Cloud resources, including organizational roles and responsibilities of the NASA project and DAAC personnel. Scenarios we use to further distinguish between what the system will do and what configuration and controls operators will have. Examples include interactions with data providers and data consumers with both in-cloud and on-premise facilities

A Pilot Study into the Value of 3-D Sketch Modelling at Key Stage 3

Modelling is fundamental to design and technology. From the initial image in the mind, a cognitive model, right the way through until the final product designers use models. They can use drawings or sketches, 2- D modelling, 3-D sketch modelling or mock ups, mathematical and/or computer models, and prototypes. This paper is an account of a pilot study into the value of the use of one type of model, the 3-D sketch model, when used by Key Stage 3 pupils when designing a product to be made in the area known in the English National Curriculum as resistant materials. The pilot study was conducted at a rural comprehensive community college. The researchers first reviewed the extent of the use of 3-D sketch models by pupils in Year 9. They found that little use was made of this way of developing design ideas and solving problems. In conjunction with the school staff a revised approach to a resistant materials project was set up to include the use o

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