Exploiting open standards in academic web services

In Digital Library-related technologies, there is a whole host of open standards and protocols that are at varying stages of definition or emergence and acceptance or agreement. Nevertheless, specifically in an academic context, these have led to some valuable improvements in the quality and value of services provided to teachers, learners and researchers alike. However, it often remains difficult for these information seekers to find relevant resources that are not immediately 'visible', they may be effectively hidden within database-driven web services or proprietary applications. The focus of this paper is upon a project based at the UK academic data centre, MIMAS, which provides web-based services to the education community in the UK, Ireland and beyond. The project's principle aim was to increase the visibility and accessibility of 'appropriate' resources by exploiting a number of relevant open standards and initiatives to ensure interoperability. This principally required focusing on machine-to-machine metadata interchange

Narrative Quilts and Quilted Narratives: The Art of Faith Ringgold and Alice Walker

There have been two main streams of influence on Chicano artists aside from the obvious one that is the result of their artistic training, education and development in the United States. The primary influence came from Mexico, first during the colonial period in the form of New Spanish art and architecture, and then in modem times provided by the Mexican muralists through their work and their use of pre-Columbian art. The New Spanish materials formed the nucleus for the second stream of influence composed of the various manifestations of religious folk art found primarily in the Southwest

Evaluating complex digital resources

Squires (1999) discussed the gap between HCI (Human Computer Interaction) and the educational computing communities in their very different approaches to evaluating educational software. This paper revisits that issue in the context of evaluating digital resources, focusing on two approaches to evaluation: an HCI and an educational perspective. Squires and Preece's HCI evaluation model is a predictive model ‐ it helps teachers decide whether or not to use educational software ‐ whilst our own concern is in evaluating the use of learning technologies. It is suggested that in part the different approaches of the two communities relate to the different focus that each takes: in HCI the focus is typically on development and hence usability, whilst in education the concern is with the learner and teacher use

Investigation of the Optical Properties of PbSe/PbX Nanocrystals for Photodetector Applications

Lead selenide and lead selenide/lead sulfide core/shell nanocrystals were investigated for use in near infrared photodetectors. A colloidal synthesis method was used for both the core and core/shell configurations. The lead sulfide shell was examined in order to mitigate oxidation of the nanoparticle surface. Absorbance and photoluminescence spectra were measured at room temperature and 77 K, respectively. Transmission electron microscopy images were also obtained to confirm crystallography and size. Bulk lead selenide was simulated in WIEN2k utilizing the linear-augmented plane wave method of solving density functional theory to better understand the electronic structure of PbSe. The crystal structure, electron density, band structure and density of states are presented and discussed. The calculations correctly predicted a direct band gap at the L point in the Brillouin zone. The band gap calculated was 0.40 eV

Kinetic and product studies involving thionitrites

The kinetics of nitrosation of cysteine, cysteine methyl ester, N-acetylcysteine, penicillamine, N-acetylpenicillamine, glutathione and thioglycolic acid was undertaken. These thiols exhibited identical rate laws which are interpreted as nitrosation at sulphur by H(_2)NO(_2)(^+)/NO(^+). The rate constants determined show the high reactivity of thiols towards the nitrosating agent. The nucleophile catalyzed reactions were also investigated and the order of reactivity NOCl > NOBr > NOSCN was observed. Normally in these nucleophile catalyzed reactions there is a first order dependence on [thiol]. However, for N-acetylcysteine and thioglycolic' acid at high [thiol] the rate of formation of NOX tends to become the rate determining stage. The difference in rate constants between cysteine and penicillamine and their N-acetyl derivatives is explained in terms of internal stabilization. The decomposition of S-nitrosocysteine (S-NOCys) at pH 5.5, 7 and 9.8 in the presence and absence of C1(^-), Br(^-) and SCN(^-), and also alanine and sodium bicarbonate at pH 7, and S-nitrosoglutathione (GS-NO) at pH 7 in the presence and absence of alanine, C1(^-), and sodium bicarbonate was studied. The decomposition profiles were complex, but showed that S-NOCys was least stable at pH 7, and that GS-NO was more stable than S-NOCys. The addition of the aforementioned species did not significantly affect the rate of decomposition of the thionitrites. Finally the potential of S-NOCys, GS-NO and S-nitroso-N-acetyl- penicillamine as nitrosating agents towards amines was investigated at pH 7 and pH 8. These thionitrites nitrosated morpholine to give approximately the same yield of N-nitrosomorpholine (ca -17%) at pH 7, and less at pH 8 for S-NOCys and GS-NO. The addition of sodium acetate, sodium chloride, sodium bicarbonate, alanine and glucose, compounds liable to be present in vivo, did not significantly affect the yield of N-nitrosomorpholine. The transnitrosation reaction was complete before total decomposition of the thionitrite and a direct reaction between the thionitrite and morpholine is proposed

Influence of nutrient availability on soil respiration and microbial activity in a tree-grass ecosystem

Increased availability of nitrogen (N) and phosphorus (P) due to human activity has potential to increase carbon (C) stocks if it leads to added plant productivity. Whether increased productivity leads to changes in ecosystem C stocks is dependent on if processing of C by soil microbes is also increased by nutrient addition or its stoichiometry. Likely, the response of soil C cycling to changes in N:P depends on site fertility. In tree-grass ecosystems, like oak-savannas, there is variation in soil organic C (SOC) due to in situ decomposition of tree litter. The aim of this work is to quantify how N:P availability affects C cycling in oak-savanna soil habitats. We found that soil respiration and its response to nutrient addition differed between habitats. Open grassland had higher respiration with N addition while soil under canopies had the opposite, confirming that SOC content modifies soil respiration response to nutrient addition. A second approach examined ecosystem allocation of added N using a stable isotope tracer. Open grassland with high N:P had the most label recovery; meaning that it is more N-limited than under canopy. A final tract looked at changes in microbial activity after N and P addition where carbon-use efficiency (CUE) was measured on soils with short or long-term fertilization history. Treatments had no effect on CUE under canopies. Grassland had lower CUE when single nutrients were added in the short-term, but unchanged when combined. Thus, stoichiometric imbalance reduces CUE in the short term, but more study is needed. Overall, oak-savanna microbial activity is not nutrient-limited, but limited by C availability. Grassland soil of oak-savannas is more sensitive to changes in nutrient availability than that under canopies. Grassland soil C is more susceptible to loss when N:P stoichiometry is higher due to increased respiration. Greater mechanistic understanding is needed of how N and P alter microbial activity

The Effect of Induced Cardiovascular Fatigue on the Performance and Learning of an Eye-Hand Coordination Novel Task for Junior High School Students

No abstract made available

Can a Work Organization Have an Attitude Problem? The Impact of Workplaces on Employee Attitudes and Economic Outcomes

Using the employee opinion survey responses from several thousand employees working in 193 branches of a major U.S. bank, we consider whether there is a distinctive workplace component to employee attitudes despite the common set of corporate human resource management practices that cover all the branches. Several different empirical tests consistently point to the existence of a systematic branch-specific component to employee attitudes. “Branch effects” can also explain why a significant positive cross-sectional correlation between branch-level employee attitudes and branch sales performance is not observed in longitudinal fixed-effects sales models. The results of our empirical tests concerning the determinants of employee attitudes and the determinants of branch sales are consistent with an interpretation that workplace-specific factors lead to better outcomes for both employees and the bank, and that these factors are more likely to be some aspect of the branches’ internal operations rather than some characteristic of the external market of the branch.