Molecular Precursors in Aqueous Solution for CIGSe Solar Cells

Thin film solar cells are one of the most promising alternatives to traditional silicon based solar cells. Copper, indium, gallium, and sufur/selenium (CIGS) act as the absorber layer in one type of thin films. CIGS films are preferable to silicon because they can have wider applications, such as flexible solar cells. The highest efficiency CIGS solar cells have been made using either expensive vacuum equipment or highly toxic chemicals. This study investigates non-toxic molecular precursor solutions deposited by spray coating. Stoichiometric amounts of CIGS are dissolved in ammonium thioglycolate and ammonium hydroxide to create the molecular precursor solution. This solution is then spray coated onto a molybdenum coated glass substrate. The CIGS coated substrate is then selenized to encourage crystal growth. The selenized substrate is then made into a full solar device. The research concluded that one can successfully dissolve molecular precursors in water-based solvents and deposit the solution onto a substrate. With some improvements in deposition and the solution’s ability to wet the molybdenum, CIGS solar cells could be made using nontoxic, water-based solvents

Computer-Aided Fabrication System Structure

Contains report on one research project.Defense Advanced Research Projects Agency Contract MDA 972 88-K-000

Computer-Aided Fabrication System Structure

Contains reports on one research project.Defense Advanced Research Projects Agency MDA 972 88-K-000

Computer-Assisted Prototyping of Advanced Microsystems

Contains reports on five research projects.Defense Advanced Research Projects Agency Contract DABT 63-95-C-0088Stanford Universit

H2AX phosphorylation screen of cells from radiosensitive cancer patients reveals a novel DNA double-strand break repair cellular phenotype

BACKGROUND: About 1-5% of cancer patients suffer from significant normal tissue reactions as a result of radiotherapy (RT). It is not possible at this time to predict how most patients' normal tissues will respond to RT. DNA repair dysfunction is implicated in sensitivity to RT particularly in genes that mediate the repair of DNA double-strand breaks (DSBs). Phosphorylation of histone H2AX (phosphorylated molecules are known as gammaH2AX) occurs rapidly in response to DNA DSBs, and, among its other roles, contributes to repair protein recruitment to these damaged sites. Mammalian cell lines have also been crucial in facilitating the successful cloning of many DNA DSB repair genes; yet, very few mutant cell lines exist for non-syndromic clinical radiosensitivity (RS).\ud \ud METHODS: Here, we survey DNA DSB induction and repair in whole cells from RS patients, as revealed by gammaH2AX foci assays, as potential predictive markers of clinical radiation response.\ud \ud RESULTS: With one exception, both DNA focus induction and repair in cell lines from RS patients were comparable with controls. Using gammaH2AX foci assays, we identified a RS cancer patient cell line with a novel ionising radiation-induced DNA DSB repair defect; these data were confirmed by an independent DNA DSB repair assay.\ud \ud CONCLUSION: gammaH2AX focus measurement has limited scope as a pre-RT predictive assay in lymphoblast cell lines from RT patients; however, the assay can successfully identify novel DNA DSB repair-defective patient cell lines, thus potentially facilitating the discovery of novel constitutional contributions to clinical RS

Towards an ethical ecology of international service learning

International Service-Learning (ISL) is a pedagogical activity that seeks to blend student learning with community engagement overseas and the development of a more just society. ISL programmes have grown as educational institutions and non-governmental organisations have sought to achieve the goal of developing ‘global citizens’. However, Service Learning (SL) in general and International Service-Learning (ISL) in particular remain deeply under theorised. These educational initiatives provide policy makers with a practical response to their quest for a ‘Big Society’and present alluring pedagogical approaches for Universities as they react to reforms in Higher Education and seek to enhance both the student learning experience and graduate employability. After outlining the development of ISL in policy and practice, this paper draws on the rich tradition of ISL at one British university to argue that ISL is a form of engagement that has the potential to be ethical in character although we identify a number of factors that militate against this. Our contention is that ISL which promotes rationaland instrumental learning represents a deficit model and we therefore conceptualise ISL here as a transformative learning experience that evinces distinctly aesthetic and even spiritual dimensions. Upon this theoretical groundwork we lay the foundations for conceptualizing ISL in ways that ensure its ethical integrity